diff options
48 files changed, 1898 insertions, 785 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 36d6ce7cc886..b93aaa374266 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3903,6 +3903,13 @@ Format: {"off"} Disable Hardware Transactional Memory + preempt= [KNL] + Select preemption mode if you have CONFIG_PREEMPT_DYNAMIC + none - Limited to cond_resched() calls + voluntary - Limited to cond_resched() and might_sleep() calls + full - Any section that isn't explicitly preempt disabled + can be preempted anytime. + print-fatal-signals= [KNL] debug: print fatal signals diff --git a/Documentation/scheduler/schedutil.txt b/Documentation/scheduler/schedutil.txt new file mode 100644 index 000000000000..78f6b91e2291 --- /dev/null +++ b/Documentation/scheduler/schedutil.txt @@ -0,0 +1,169 @@ + + +NOTE; all this assumes a linear relation between frequency and work capacity, +we know this is flawed, but it is the best workable approximation. + + +PELT (Per Entity Load Tracking) +------------------------------- + +With PELT we track some metrics across the various scheduler entities, from +individual tasks to task-group slices to CPU runqueues. As the basis for this +we use an Exponentially Weighted Moving Average (EWMA), each period (1024us) +is decayed such that y^32 = 0.5. That is, the most recent 32ms contribute +half, while the rest of history contribute the other half. + +Specifically: + + ewma_sum(u) := u_0 + u_1*y + u_2*y^2 + ... + + ewma(u) = ewma_sum(u) / ewma_sum(1) + +Since this is essentially a progression of an infinite geometric series, the +results are composable, that is ewma(A) + ewma(B) = ewma(A+B). This property +is key, since it gives the ability to recompose the averages when tasks move +around. + +Note that blocked tasks still contribute to the aggregates (task-group slices +and CPU runqueues), which reflects their expected contribution when they +resume running. + +Using this we track 2 key metrics: 'running' and 'runnable'. 'Running' +reflects the time an entity spends on the CPU, while 'runnable' reflects the +time an entity spends on the runqueue. When there is only a single task these +two metrics are the same, but once there is contention for the CPU 'running' +will decrease to reflect the fraction of time each task spends on the CPU +while 'runnable' will increase to reflect the amount of contention. + +For more detail see: kernel/sched/pelt.c + + +Frequency- / CPU Invariance +--------------------------- + +Because consuming the CPU for 50% at 1GHz is not the same as consuming the CPU +for 50% at 2GHz, nor is running 50% on a LITTLE CPU the same as running 50% on +a big CPU, we allow architectures to scale the time delta with two ratios, one +Dynamic Voltage and Frequency Scaling (DVFS) ratio and one microarch ratio. + +For simple DVFS architectures (where software is in full control) we trivially +compute the ratio as: + + f_cur + r_dvfs := ----- + f_max + +For more dynamic systems where the hardware is in control of DVFS we use +hardware counters (Intel APERF/MPERF, ARMv8.4-AMU) to provide us this ratio. +For Intel specifically, we use: + + APERF + f_cur := ----- * P0 + MPERF + + 4C-turbo; if available and turbo enabled + f_max := { 1C-turbo; if turbo enabled + P0; otherwise + + f_cur + r_dvfs := min( 1, ----- ) + f_max + +We pick 4C turbo over 1C turbo to make it slightly more sustainable. + +r_cpu is determined as the ratio of highest performance level of the current +CPU vs the highest performance level of any other CPU in the system. + + r_tot = r_dvfs * r_cpu + +The result is that the above 'running' and 'runnable' metrics become invariant +of DVFS and CPU type. IOW. we can transfer and compare them between CPUs. + +For more detail see: + + - kernel/sched/pelt.h:update_rq_clock_pelt() + - arch/x86/kernel/smpboot.c:"APERF/MPERF frequency ratio computation." + - Documentation/scheduler/sched-capacity.rst:"1. CPU Capacity + 2. Task utilization" + + +UTIL_EST / UTIL_EST_FASTUP +-------------------------- + +Because periodic tasks have their averages decayed while they sleep, even +though when running their expected utilization will be the same, they suffer a +(DVFS) ramp-up after they are running again. + +To alleviate this (a default enabled option) UTIL_EST drives an Infinite +Impulse Response (IIR) EWMA with the 'running' value on dequeue -- when it is +highest. A further default enabled option UTIL_EST_FASTUP modifies the IIR +filter to instantly increase and only decay on decrease. + +A further runqueue wide sum (of runnable tasks) is maintained of: + + util_est := \Sum_t max( t_running, t_util_est_ewma ) + +For more detail see: kernel/sched/fair.c:util_est_dequeue() + + +UCLAMP +------ + +It is possible to set effective u_min and u_max clamps on each CFS or RT task; +the runqueue keeps an max aggregate of these clamps for all running tasks. + +For more detail see: include/uapi/linux/sched/types.h + + +Schedutil / DVFS +---------------- + +Every time the scheduler load tracking is updated (task wakeup, task +migration, time progression) we call out to schedutil to update the hardware +DVFS state. + +The basis is the CPU runqueue's 'running' metric, which per the above it is +the frequency invariant utilization estimate of the CPU. From this we compute +a desired frequency like: + + max( running, util_est ); if UTIL_EST + u_cfs := { running; otherwise + + clamp( u_cfs + u_rt , u_min, u_max ); if UCLAMP_TASK + u_clamp := { u_cfs + u_rt; otherwise + + u := u_clamp + u_irq + u_dl; [approx. see source for more detail] + + f_des := min( f_max, 1.25 u * f_max ) + +XXX IO-wait; when the update is due to a task wakeup from IO-completion we +boost 'u' above. + +This frequency is then used to select a P-state/OPP or directly munged into a +CPPC style request to the hardware. + +XXX: deadline tasks (Sporadic Task Model) allows us to calculate a hard f_min +required to satisfy the workload. + +Because these callbacks are directly from the scheduler, the DVFS hardware +interaction should be 'fast' and non-blocking. Schedutil supports +rate-limiting DVFS requests for when hardware interaction is slow and +expensive, this reduces effectiveness. + +For more information see: kernel/sched/cpufreq_schedutil.c + + +NOTES +----- + + - On low-load scenarios, where DVFS is most relevant, the 'running' numbers + will closely reflect utilization. + + - In saturated scenarios task movement will cause some transient dips, + suppose we have a CPU saturated with 4 tasks, then when we migrate a task + to an idle CPU, the old CPU will have a 'running' value of 0.75 while the + new CPU will gain 0.25. This is inevitable and time progression will + correct this. XXX do we still guarantee f_max due to no idle-time? + + - Much of the above is about avoiding DVFS dips, and independent DVFS domains + having to re-learn / ramp-up when load shifts. + diff --git a/arch/Kconfig b/arch/Kconfig index 87608c2fa027..4790a5f23d9f 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -1058,6 +1058,15 @@ config HAVE_STATIC_CALL_INLINE bool depends on HAVE_STATIC_CALL +config HAVE_PREEMPT_DYNAMIC + bool + depends on HAVE_STATIC_CALL + depends on GENERIC_ENTRY + help + Select this if the architecture support boot time preempt setting + on top of static calls. It is strongly advised to support inline + static call to avoid any overhead. + config ARCH_WANT_LD_ORPHAN_WARN bool help diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c index 9d06fffb1526..369206489895 100644 --- a/arch/powerpc/platforms/cell/spufs/sched.c +++ b/arch/powerpc/platforms/cell/spufs/sched.c @@ -72,7 +72,7 @@ static struct timer_list spuloadavg_timer; #define DEF_SPU_TIMESLICE (100 * HZ / (1000 * SPUSCHED_TICK)) #define SCALE_PRIO(x, prio) \ - max(x * (MAX_PRIO - prio) / (MAX_USER_PRIO / 2), MIN_SPU_TIMESLICE) + max(x * (MAX_PRIO - prio) / (NICE_WIDTH / 2), MIN_SPU_TIMESLICE) /* * scale user-nice values [ -20 ... 0 ... 19 ] to time slice values: diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7b934a591df2..595193bc2d31 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -224,6 +224,7 @@ config X86 select HAVE_STACK_VALIDATION if X86_64 select HAVE_STATIC_CALL select HAVE_STATIC_CALL_INLINE if HAVE_STACK_VALIDATION + select HAVE_PREEMPT_DYNAMIC select HAVE_RSEQ select HAVE_SYSCALL_TRACEPOINTS select HAVE_UNSTABLE_SCHED_CLOCK diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h index 69485ca13665..f8cb8af4de5c 100644 --- a/arch/x86/include/asm/preempt.h +++ b/arch/x86/include/asm/preempt.h @@ -5,6 +5,7 @@ #include <asm/rmwcc.h> #include <asm/percpu.h> #include <linux/thread_info.h> +#include <linux/static_call_types.h> DECLARE_PER_CPU(int, __preempt_count); @@ -103,16 +104,45 @@ static __always_inline bool should_resched(int preempt_offset) } #ifdef CONFIG_PREEMPTION - extern asmlinkage void preempt_schedule_thunk(void); -# define __preempt_schedule() \ - asm volatile ("call preempt_schedule_thunk" : ASM_CALL_CONSTRAINT) - extern asmlinkage void preempt_schedule(void); - extern asmlinkage void preempt_schedule_notrace_thunk(void); -# define __preempt_schedule_notrace() \ - asm volatile ("call preempt_schedule_notrace_thunk" : ASM_CALL_CONSTRAINT) +extern asmlinkage void preempt_schedule(void); +extern asmlinkage void preempt_schedule_thunk(void); - extern asmlinkage void preempt_schedule_notrace(void); -#endif +#define __preempt_schedule_func preempt_schedule_thunk + +extern asmlinkage void preempt_schedule_notrace(void); +extern asmlinkage void preempt_schedule_notrace_thunk(void); + +#define __preempt_schedule_notrace_func preempt_schedule_notrace_thunk + +#ifdef CONFIG_PREEMPT_DYNAMIC + +DECLARE_STATIC_CALL(preempt_schedule, __preempt_schedule_func); + +#define __preempt_schedule() \ +do { \ + __STATIC_CALL_MOD_ADDRESSABLE(preempt_schedule); \ + asm volatile ("call " STATIC_CALL_TRAMP_STR(preempt_schedule) : ASM_CALL_CONSTRAINT); \ +} while (0) + +DECLARE_STATIC_CALL(preempt_schedule_notrace, __preempt_schedule_notrace_func); + +#define __preempt_schedule_notrace() \ +do { \ + __STATIC_CALL_MOD_ADDRESSABLE(preempt_schedule_notrace); \ + asm volatile ("call " STATIC_CALL_TRAMP_STR(preempt_schedule_notrace) : ASM_CALL_CONSTRAINT); \ +} while (0) + +#else /* PREEMPT_DYNAMIC */ + +#define __preempt_schedule() \ + asm volatile ("call preempt_schedule_thunk" : ASM_CALL_CONSTRAINT); + +#define __preempt_schedule_notrace() \ + asm volatile ("call preempt_schedule_notrace_thunk" : ASM_CALL_CONSTRAINT); + +#endif /* PREEMPT_DYNAMIC */ + +#endif /* PREEMPTION */ #endif /* __ASM_PREEMPT_H */ diff --git a/arch/x86/include/asm/static_call.h b/arch/x86/include/asm/static_call.h index c37f11999d0c..cbb67b6030f9 100644 --- a/arch/x86/include/asm/static_call.h +++ b/arch/x86/include/asm/static_call.h @@ -37,4 +37,11 @@ #define ARCH_DEFINE_STATIC_CALL_NULL_TRAMP(name) \ __ARCH_DEFINE_STATIC_CALL_TRAMP(name, "ret; nop; nop; nop; nop") + +#define ARCH_ADD_TRAMP_KEY(name) \ + asm(".pushsection .static_call_tramp_key, \"a\" \n" \ + ".long " STATIC_CALL_TRAMP_STR(name) " - . \n" \ + ".long " STATIC_CALL_KEY_STR(name) " - . \n" \ + ".popsection \n") + #endif /* _ASM_STATIC_CALL_H */ diff --git a/arch/x86/kernel/static_call.c b/arch/x86/kernel/static_call.c index ca9a380d9c0b..9442c4136c38 100644 --- a/arch/x86/kernel/static_call.c +++ b/arch/x86/kernel/static_call.c @@ -11,14 +11,26 @@ enum insn_type { RET = 3, /* tramp / site cond-tail-call */ }; +/* + * data16 data16 xorq %rax, %rax - a single 5 byte instruction that clears %rax + * The REX.W cancels the effect of any data16. + */ +static const u8 xor5rax[] = { 0x66, 0x66, 0x48, 0x31, 0xc0 }; + static void __ref __static_call_transform(void *insn, enum insn_type type, void *func) { + const void *emulate = NULL; int size = CALL_INSN_SIZE; const void *code; switch (type) { case CALL: code = text_gen_insn(CALL_INSN_OPCODE, insn, func); + if (func == &__static_call_return0) { + emulate = code; + code = &xor5rax; + } + break; case NOP: @@ -41,7 +53,7 @@ static void __ref __static_call_transform(void *insn, enum insn_type type, void if (unlikely(system_state == SYSTEM_BOOTING)) return text_poke_early(insn, code, size); - text_poke_bp(insn, code, size, NULL); + text_poke_bp(insn, code, size, emulate); } static void __static_call_validate(void *insn, bool tail) @@ -54,7 +66,8 @@ static void __static_call_validate(void *insn, bool tail) return; } else { if (opcode == CALL_INSN_OPCODE || - !memcmp(insn, ideal_nops[NOP_ATOMIC5], 5)) + !memcmp(insn, ideal_nops[NOP_ATOMIC5], 5) || + !memcmp(insn, xor5rax, 5)) return; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 1b404e4d7dd8..b967c1c774a1 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1782,6 +1782,7 @@ EXPORT_SYMBOL_GPL(kvm_emulate_wrmsr); bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu) { + xfer_to_guest_mode_prepare(); return vcpu->mode == EXITING_GUEST_MODE || kvm_request_pending(vcpu) || xfer_to_guest_mode_work_pending(); } diff --git a/drivers/thermal/cpufreq_cooling.c b/drivers/thermal/cpufreq_cooling.c index 612f063c1cfc..f5af2571f9b7 100644 --- a/drivers/thermal/cpufreq_cooling.c +++ b/drivers/thermal/cpufreq_cooling.c @@ -76,7 +76,9 @@ struct cpufreq_cooling_device { struct em_perf_domain *em; struct cpufreq_policy *policy; struct list_head node; +#ifndef CONFIG_SMP struct time_in_idle *idle_time; +#endif struct freq_qos_request qos_req; }; @@ -132,14 +134,25 @@ static u32 cpu_power_to_freq(struct cpufreq_cooling_device *cpufreq_cdev, } /** - * get_load() - get load for a cpu since last updated - * @cpufreq_cdev: &struct cpufreq_cooling_device for this cpu - * @cpu: cpu number - * @cpu_idx: index of the cpu in time_in_idle* + * get_load() - get load for a cpu + * @cpufreq_cdev: struct cpufreq_cooling_device for the cpu + * @cpu: cpu number + * @cpu_idx: index of the cpu in time_in_idle array * * Return: The average load of cpu @cpu in percentage since this * function was last called. */ +#ifdef CONFIG_SMP +static u32 get_load(struct cpufreq_cooling_device *cpufreq_cdev, int cpu, + int cpu_idx) +{ + unsigned long max = arch_scale_cpu_capacity(cpu); + unsigned long util; + + util = sched_cpu_util(cpu, max); + return (util * 100) / max; +} +#else /* !CONFIG_SMP */ static u32 get_load(struct cpufreq_cooling_device *cpufreq_cdev, int cpu, int cpu_idx) { @@ -161,6 +174,7 @@ static u32 get_load(struct cpufreq_cooling_device *cpufreq_cdev, int cpu, return load; } +#endif /* CONFIG_SMP */ /** * get_dynamic_power() - calculate the dynamic power @@ -346,6 +360,36 @@ static inline bool em_is_sane(struct cpufreq_cooling_device *cpufreq_cdev, } #endif /* CONFIG_THERMAL_GOV_POWER_ALLOCATOR */ +#ifdef CONFIG_SMP +static inline int allocate_idle_time(struct cpufreq_cooling_device *cpufreq_cdev) +{ + return 0; +} + +static inline void free_idle_time(struct cpufreq_cooling_device *cpufreq_cdev) +{ +} +#else +static int allocate_idle_time(struct cpufreq_cooling_device *cpufreq_cdev) +{ + unsigned int num_cpus = cpumask_weight(cpufreq_cdev->policy->related_cpus); + + cpufreq_cdev->idle_time = kcalloc(num_cpus, + sizeof(*cpufreq_cdev->idle_time), + GFP_KERNEL); + if (!cpufreq_cdev->idle_time) + return -ENOMEM; + + return 0; +} + +static void free_idle_time(struct cpufreq_cooling_device *cpufreq_cdev) +{ + kfree(cpufreq_cdev->idle_time); + cpufreq_cdev->idle_time = NULL; +} +#endif /* CONFIG_SMP */ + static unsigned int get_state_freq(struct cpufreq_cooling_device *cpufreq_cdev, unsigned long state) { @@ -485,7 +529,7 @@ __cpufreq_cooling_register(struct device_node *np, struct thermal_cooling_device *cdev; struct cpufreq_cooling_device *cpufreq_cdev; char dev_name[THERMAL_NAME_LENGTH]; - unsigned int i, num_cpus; + unsigned int i; struct device *dev; int ret; struct thermal_cooling_device_ops *cooling_ops; @@ -496,7 +540,6 @@ __cpufreq_cooling_register(struct device_node *np, return ERR_PTR(-ENODEV); } - if (IS_ERR_OR_NULL(policy)) { pr_err("%s: cpufreq policy isn't valid: %p\n", __func__, policy); return ERR_PTR(-EINVAL); @@ -514,12 +557,10 @@ __cpufreq_cooling_register(struct device_node *np, return ERR_PTR(-ENOMEM); cpufreq_cdev->policy = policy; - num_cpus = cpumask_weight(policy->related_cpus); - cpufreq_cdev->idle_time = kcalloc(num_cpus, - sizeof(*cpufreq_cdev->idle_time), - GFP_KERNEL); - if (!cpufreq_cdev->idle_time) { - cdev = ERR_PTR(-ENOMEM); + + ret = allocate_idle_time(cpufreq_cdev); + if (ret) { + cdev = ERR_PTR(ret); goto free_cdev; } @@ -579,7 +620,7 @@ remove_qos_req: remove_ida: ida_simple_remove(&cpufreq_ida, cpufreq_cdev->id); free_idle_time: - kfree(cpufreq_cdev->idle_time); + free_idle_time(cpufreq_cdev); free_cdev: kfree(cpufreq_cdev); return cdev; @@ -672,7 +713,7 @@ void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev) thermal_cooling_device_unregister(cdev); freq_qos_remove_request(&cpufreq_cdev->qos_req); ida_simple_remove(&cpufreq_ida, cpufreq_cdev->id); - kfree(cpufreq_cdev->idle_time); + free_idle_time(cpufreq_cdev); kfree(cpufreq_cdev); } EXPORT_SYMBOL_GPL(cpufreq_cooling_unregister); diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 52dbd58f6810..a54e08d77789 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -403,7 +403,10 @@ . = ALIGN(8); \ __start_static_call_sites = .; \ KEEP(*(.static_call_sites)) \ - __stop_static_call_sites = .; + __stop_static_call_sites = .; \ + __start_static_call_tramp_key = .; \ + KEEP(*(.static_call_tramp_key)) \ + __stop_static_call_tramp_key = .; /* * Allow architectures to handle ro_after_init data on their diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 451c2d26a5db..4f2f79de083e 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -307,7 +307,7 @@ void css_task_iter_end(struct css_task_iter *it); * Inline functions. */ -static inline u64 cgroup_id(struct cgroup *cgrp) +static inline u64 cgroup_id(const struct cgroup *cgrp) { return cgrp->kn->id; } @@ -701,7 +701,7 @@ void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen); struct cgroup_subsys_state; struct cgroup; -static inline u64 cgroup_id(struct cgroup *cgrp) { return 1; } +static inline u64 cgroup_id(const struct cgroup *cgrp) { return 1; } static inline void css_get(struct cgroup_subsys_state *css) {} static inline void css_put(struct cgroup_subsys_state *css) {} static inline int cgroup_attach_task_all(struct task_struct *from, diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index a104b298019a..883acef895bc 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -2,6 +2,7 @@ #ifndef __LINUX_ENTRYCOMMON_H #define __LINUX_ENTRYCOMMON_H +#include <linux/static_call_types.h> #include <linux/tracehook.h> #include <linux/syscalls.h> #include <linux/seccomp.h> @@ -454,6 +455,9 @@ irqentry_state_t noinstr irqentry_enter(struct pt_regs *regs); * Conditional reschedule with additional sanity checks. */ void irqentry_exit_cond_resched(void); +#ifdef CONFIG_PREEMPT_DYNAMIC +DECLARE_STATIC_CALL(irqentry_exit_cond_resched, irqentry_exit_cond_resched); +#endif /** * irqentry_exit - Handle return from exception that used irqentry_enter() diff --git a/include/linux/entry-kvm.h b/include/linux/entry-kvm.h index 9b93f8584ff7..8b2b1d68b954 100644 --- a/include/linux/entry-kvm.h +++ b/include/linux/entry-kvm.h @@ -47,6 +47,20 @@ static inline int arch_xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu, int xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu); /** + * xfer_to_guest_mode_prepare - Perform last minute preparation work that + * need to be handled while IRQs are disabled + * upon entering to guest. + * + * Has to be invoked with interrupts disabled before the last call + * to xfer_to_guest_mode_work_pending(). + */ +static inline void xfer_to_guest_mode_prepare(void) +{ + lockdep_assert_irqs_disabled(); + rcu_nocb_flush_deferred_wakeup(); +} + +/** * __xfer_to_guest_mode_work_pending - Check if work is pending * * Returns: True if work pending, False otherwise. diff --git a/include/linux/kernel.h b/include/linux/kernel.h index f7902d8c1048..5b7ed6dc99ac 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -15,7 +15,7 @@ #include <linux/typecheck.h> #include <linux/printk.h> #include <linux/build_bug.h> - +#include <linux/static_call_types.h> #include <asm/byteorder.h> #include <uapi/linux/kernel.h> @@ -81,11 +81,26 @@ struct pt_regs; struct user; #ifdef CONFIG_PREEMPT_VOLUNTARY -extern int _cond_resched(void); -# define might_resched() _cond_resched() + +extern int __cond_resched(void); +# define might_resched() __cond_resched() + +#elif defined(CONFIG_PREEMPT_DYNAMIC) + +extern int __cond_resched(void); + +DECLARE_STATIC_CALL(might_resched, __cond_resched); + +static __always_inline void might_resched(void) +{ + static_call_mod(might_resched)(); +} + #else + # define might_resched() do { } while (0) -#endif + +#endif /* CONFIG_PREEMPT_* */ #ifdef CONFIG_DEBUG_ATOMIC_SLEEP extern void ___might_sleep(const char *file, int line, int preempt_offset); diff --git a/include/linux/rbtree.h b/include/linux/rbtree.h index d7db17996322..d31ecaf4fdd3 100644 --- a/include/linux/rbtree.h +++ b/include/linux/rbtree.h @@ -141,12 +141,18 @@ static inline void rb_insert_color_cached(struct rb_node *node, rb_insert_color(node, &root->rb_root); } -static inline void rb_erase_cached(struct rb_node *node, - struct rb_root_cached *root) + +static inline struct rb_node * +rb_erase_cached(struct rb_node *node, struct rb_root_cached *root) { + struct rb_node *leftmost = NULL; + if (root->rb_leftmost == node) - root->rb_leftmost = rb_next(node); + leftmost = root->rb_leftmost = rb_next(node); + rb_erase(node, &root->rb_root); + + return leftmost; } static inline void rb_replace_node_cached(struct rb_node *victim, @@ -158,4 +164,198 @@ static inline void rb_replace_node_cached(struct rb_node *victim, rb_replace_node(victim, new, &root->rb_root); } +/* + * The below helper functions use 2 operators with 3 different + * calling conventions. The operators are related like: + * + * comp(a->key,b) < 0 := less(a,b) + * comp(a->key,b) > 0 := less(b,a) + * comp(a->key,b) == 0 := !less(a,b) && !less(b,a) + * + * If these operators define a partial order on the elements we make no + * guarantee on which of the elements matching the key is found. See + * rb_find(). + * + * The reason for this is to allow the find() interface without requiring an + * on-stack dummy object, which might not be feasible due to object size. + */ + +/** + * rb_add_cached() - insert @node into the leftmost cached tree @tree + * @node: node to insert + * @tree: leftmost cached tree to insert @node into + * @less: operator defining the (partial) node order + * + * Returns @node when it is the new leftmost, or NULL. + */ +static __always_inline struct rb_node * +rb_add_cached(struct rb_node *node, struct rb_root_cached *tree, + bool (*less)(struct rb_node *, const struct rb_node *)) +{ + struct rb_node **link = &tree->rb_root.rb_node; + struct rb_node *parent = NULL; + bool leftmost = true; + + while (*link) { + parent = *link; + if (less(node, parent)) { + link = &parent->rb_left; + } else { + link = &parent->rb_right; + leftmost = false; + } + } + + rb_link_node(node, parent, link); + rb_insert_color_cached(node, tree, leftmost); + + return leftmost ? node : NULL; +} + +/** + * rb_add() - insert @node into @tree + * @node: node to insert + * @tree: tree to insert @node into + * @less: operator defining the (partial) node order + */ +static __always_inline void +rb_add(struct rb_node *node, struct rb_root *tree, + bool (*less)(struct rb_node *, const struct rb_node *)) +{ + struct rb_node **link = &tree->rb_node; + struct rb_node *parent = NULL; + + while (*link) { + parent = *link; + if (less(node, parent)) + link = &parent->rb_left; + else + link = &parent->rb_right; + } + + rb_link_node(node, parent, link); + rb_insert_color(node, tree); +} + +/** + * rb_find_add() - find equivalent @node in @tree, or add @node + * @node: node to look-for / insert + * @tree: tree to search / modify + * @cmp: operator defining the node order + * + * Returns the rb_node matching @node, or NULL when no match is found and @node + * is inserted. + */ +static __always_inline struct rb_node * +rb_find_add(struct rb_node *node, struct rb_root *tree, + int (*cmp)(struct rb_node *, const struct rb_node *)) +{ + struct rb_node **link = &tree->rb_node; + struct rb_node *parent = NULL; + int c; + + while (*link) { + parent = *link; + c = cmp(node, parent); + + if (c < 0) + link = &parent->rb_left; + else if (c > 0) + link = &parent->rb_right; + else + return parent; + } + + rb_link_node(node, parent, link); + rb_insert_color(node, tree); + return NULL; +} + +/** + * rb_find() - find @key in tree @tree + * @key: key to match + * @tree: tree to search + * @cmp: operator defining the node order + * + * Returns the rb_node matching @key or NULL. + */ +static __always_inline struct rb_node * +rb_find(const void *key, const struct rb_root *tree, + int (*cmp)(const void *key, const struct rb_node *)) +{ + struct rb_node *node = tree->rb_node; + + while (node) { + int c = cmp(key, node); + + if (c < 0) + node = node->rb_left; + else if (c > 0) + node = node->rb_right; + else + return node; + } + + return NULL; +} + +/** + * rb_find_first() - find the first @key in @tree + * @key: key to match + * @tree: tree to search + * @cmp: operator defining node order + * + * Returns the leftmost node matching @key, or NULL. + */ +static __always_inline struct rb_node * +rb_find_first(const void *key, const struct rb_root *tree, + int (*cmp)(const void *key, const struct rb_node *)) +{ + struct rb_node *node = tree->rb_node; + struct rb_node *match = NULL; + + while (node) { + int c = cmp(key, node); + + if (c <= 0) { + if (!c) + match = node; + node = node->rb_left; + } else if (c > 0) { + node = node->rb_right; + } + } + + return match; +} + +/** + * rb_next_match() - find the next @key in @tree + * @key: key to match + * @tree: tree to search + * @cmp: operator defining node order + * + * Returns the next node matching @key, or NULL. + */ +static __always_inline struct rb_node * +rb_next_match(const void *key, struct rb_node *node, + int (*cmp)(const void *key, const struct rb_node *)) +{ + node = rb_next(node); + if (node && cmp(key, node)) + node = NULL; + return node; +} + +/** + * rb_for_each() - iterates a subtree matching @key + * @node: iterator + * @key: key to match + * @tree: tree to search + * @cmp: operator defining node order + */ +#define rb_for_each(node, key, tree, cmp) \ + for ((node) = rb_find_first((key), (tree), (cmp)); \ + (node); (node) = rb_next_match((key), (node), (cmp))) + #endif /* _LINUX_RBTREE_H */ diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index ebd8dcca4997..bd04f722714f 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -114,10 +114,12 @@ static inline void rcu_user_exit(void) { } void rcu_init_nohz(void); int rcu_nocb_cpu_offload(int cpu); int rcu_nocb_cpu_deoffload(int cpu); +void rcu_nocb_flush_deferred_wakeup(void); #else /* #ifdef CONFIG_RCU_NOCB_CPU */ static inline void rcu_init_nohz(void) { } static inline int rcu_nocb_cpu_offload(int cpu) { return -EINVAL; } static inline int rcu_nocb_cpu_deoffload(int cpu) { return 0; } +static inline void rcu_nocb_flush_deferred_wakeup(void) { } #endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */ /** diff --git a/include/linux/sched.h b/include/linux/sched.h index 6e3a5eeec509..4d568288abf9 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -47,6 +47,7 @@ struct cfs_rq; struct fs_struct; struct futex_pi_state; struct io_context; +struct io_uring_task; struct mempolicy; struct nameidata; struct nsproxy; @@ -65,7 +66,6 @@ struct sighand_struct; struct signal_struct; struct task_delay_info; struct task_group; -struct io_uring_task; /* * Task state bitmask. NOTE! These bits are also @@ -1871,11 +1871,32 @@ static inline int test_tsk_need_resched(struct task_struct *tsk) * value indicates whether a reschedule was done in fact. * cond_resched_lock() will drop the spinlock before scheduling, */ -#ifndef CONFIG_PREEMPTION -extern int _cond_resched(void); +#if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) +extern int __cond_resched(void); + +#ifdef CONFIG_PREEMPT_DYNAMIC + +DECLARE_STATIC_CALL(cond_resched, __cond_resched); + +static __always_inline int _cond_resched(void) +{ + return static_call_mod(cond_resched)(); +} + +#else + +static inline int _cond_resched(void) +{ + return __cond_resched(); +} + +#endif /* CONFIG_PREEMPT_DYNAMIC */ + #else + static inline int _cond_resched(void) { return 0; } -#endif + +#endif /* !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) */ #define cond_resched() ({ \ ___might_sleep(__FILE__, __LINE__, 0); \ @@ -1968,6 +1989,11 @@ extern long sched_getaffinity(pid_t pid, struct cpumask *mask); #define TASK_SIZE_OF(tsk) TASK_SIZE #endif +#ifdef CONFIG_SMP +/* Returns effective CPU energy utilization, as seen by the scheduler */ +unsigned long sched_cpu_util(int cpu, unsigned long max); +#endif /* CONFIG_SMP */ + #ifdef CONFIG_RSEQ /* diff --git a/include/linux/sched/prio.h b/include/linux/sched/prio.h index 7d64feafc408..ab83d85e1183 100644 --- a/include/linux/sched/prio.h +++ b/include/linux/sched/prio.h @@ -11,16 +11,9 @@ * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority * values are inverted: lower p->prio value means higher priority. - * - * The MAX_USER_RT_PRIO value allows the actual maximum - * RT priority to be separate from the value exported to - * user-space. This allows kernel threads to set their - * priority to a value higher than any user task. Note: - * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO. */ -#define MAX_USER_RT_PRIO 100 -#define MAX_RT_PRIO MAX_USER_RT_PRIO +#define MAX_RT_PRIO 100 #define MAX_PRIO (MAX_RT_PRIO + NICE_WIDTH) #define DEFAULT_PRIO (MAX_RT_PRIO + NICE_WIDTH / 2) @@ -34,15 +27,6 @@ #define PRIO_TO_NICE(prio) ((prio) - DEFAULT_PRIO) /* - * 'User priority' is the nice value converted to something we - * can work with better when scaling various scheduler parameters, - * it's a [ 0 ... 39 ] range. - */ -#define USER_PRIO(p) ((p)-MAX_RT_PRIO) -#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio) -#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO)) - -/* * Convert nice value [19,-20] to rlimit style value [1,40]. */ static inline long nice_to_rlimit(long nice) diff --git a/include/linux/static_call.h b/include/linux/static_call.h index 695da4c9b338..85ecc789f4ff 100644 --- a/include/linux/static_call.h +++ b/include/linux/static_call.h @@ -107,26 +107,10 @@ extern void arch_static_call_transform(void *site, void *tramp, void *func, bool #define STATIC_CALL_TRAMP_ADDR(name) &STATIC_CALL_TRAMP(name) -/* - * __ADDRESSABLE() is used to ensure the key symbol doesn't get stripped from - * the symbol table so that objtool can reference it when it generates the - * .static_call_sites section. - */ -#define __static_call(name) \ -({ \ - __ADDRESSABLE(STATIC_CALL_KEY(name)); \ - &STATIC_CALL_TRAMP(name); \ -}) - #else #define STATIC_CALL_TRAMP_ADDR(name) NULL #endif - -#define DECLARE_STATIC_CALL(name, func) \ - extern struct static_call_key STATIC_CALL_KEY(name); \ - extern typeof(func) STATIC_CALL_TRAMP(name); - #define static_call_update(name, func) \ ({ \ BUILD_BUG_ON(!__same_type(*(func), STATIC_CALL_TRAMP(name))); \ @@ -154,17 +138,25 @@ struct static_call_key { }; }; +/* For finding the key associated with a trampoline */ +struct static_call_tramp_key { + s32 tramp; + s32 key; +}; + extern void __static_call_update(struct static_call_key *key, void *tramp, void *func); extern int static_call_mod_init(struct module *mod); extern int static_call_text_reserved(void *start, void *end); -#define DEFINE_STATIC_CALL(name, _func) \ +extern long __static_call_return0(void); + +#define __DEFINE_STATIC_CALL(name, _func, _func_init) \ DECLARE_STATIC_CALL(name, _func); \ struct static_call_key STATIC_CALL_KEY(name) = { \ - .func = _func, \ + .func = _func_init, \ .type = 1, \ }; \ - ARCH_DEFINE_STATIC_CALL_TRAMP(name, _func) + ARCH_DEFINE_STATIC_CALL_TRAMP(name, _func_init) #define DEFINE_STATIC_CALL_NULL(name, _func) \ DECLARE_STATIC_CALL(name, _func); \ @@ -174,17 +166,23 @@ extern int static_call_text_reserved(void *start, void *end); }; \ ARCH_DEFINE_STATIC_CALL_NULL_TRAMP(name) -#define static_call(name) __static_call(name) #define static_call_cond(name) (void)__static_call(name) #define EXPORT_STATIC_CALL(name) \ EXPORT_SYMBOL(STATIC_CALL_KEY(name)); \ EXPORT_SYMBOL(STATIC_CALL_TRAMP(name)) - #define EXPORT_STATIC_CALL_GPL(name) \ EXPORT_SYMBOL_GPL(STATIC_CALL_KEY(name)); \ EXPORT_SYMBOL_GPL(STATIC_CALL_TRAMP(name)) +/* Leave the key unexported, so modules can't change static call targets: */ +#define EXPORT_STATIC_CALL_TRAMP(name) \ + EXPORT_SYMBOL(STATIC_CALL_TRAMP(name)); \ + ARCH_ADD_TRAMP_KEY(name) +#define EXPORT_STATIC_CALL_TRAMP_GPL(name) \ + EXPORT_SYMBOL_GPL(STATIC_CALL_TRAMP(name)); \ + ARCH_ADD_TRAMP_KEY(name) + #elif defined(CONFIG_HAVE_STATIC_CALL) static inline int static_call_init(void) { return 0; } @@ -193,12 +191,12 @@ struct static_call_key { void *func; }; -#define DEFINE_STATIC_CALL(name, _func) \ +#define __DEFINE_STATIC_CALL(name, _func, _func_init) \ DECLARE_STATIC_CALL(name, _func); \ struct static_call_key STATIC_CALL_KEY(name) = { \ - .func = _func, \ + .func = _func_init, \ }; \ - ARCH_DEFINE_STATIC_CALL_TRAMP(name, _func) + ARCH_DEFINE_STATIC_CALL_TRAMP(name, _func_init) #define DEFINE_STATIC_CALL_NULL(name, _func) \ DECLARE_STATIC_CALL(name, _func); \ @@ -207,7 +205,6 @@ struct static_call_key { }; \ ARCH_DEFINE_STATIC_CALL_NULL_TRAMP(name) -#define static_call(name) __static_call(name) #define static_call_cond(name) (void)__static_call(name) static inline @@ -224,14 +221,24 @@ static inline int static_call_text_reserved(void *start, void *end) return 0; } +static inline long __static_call_return0(void) +{ + return 0; +} + #define EXPORT_STATIC_CALL(name) \ EXPORT_SYMBOL(STATIC_CALL_KEY(name)); \ EXPORT_SYMBOL(STATIC_CALL_TRAMP(name)) - #define EXPORT_STATIC_CALL_GPL(name) \ EXPORT_SYMBOL_GPL(STATIC_CALL_KEY(name)); \ EXPORT_SYMBOL_GPL(STATIC_CALL_TRAMP(name)) +/* Leave the key unexported, so modules can't change static call targets: */ +#define EXPORT_STATIC_CALL_TRAMP(name) \ + EXPORT_SYMBOL(STATIC_CALL_TRAMP(name)) +#define EXPORT_STATIC_CALL_TRAMP_GPL(name) \ + EXPORT_SYMBOL_GPL(STATIC_CALL_TRAMP(name)) + #else /* Generic implementation */ static inline int static_call_init(void) { return 0; } @@ -240,10 +247,15 @@ struct static_call_key { void *func; }; -#define DEFINE_STATIC_CALL(name, _func) \ +static inline long __static_call_return0(void) +{ + return 0; +} + +#define __DEFINE_STATIC_CALL(name, _func, _func_init) \ DECLARE_STATIC_CALL(name, _func); \ struct static_call_key STATIC_CALL_KEY(name) = { \ - .func = _func, \ + .func = _func_init, \ } #define DEFINE_STATIC_CALL_NULL(name, _func) \ @@ -252,9 +264,6 @@ struct static_call_key { .func = NULL, \ } -#define static_call(name) \ - ((typeof(STATIC_CALL_TRAMP(name))*)(STATIC_CALL_KEY(name).func)) - static inline void __static_call_nop(void) { } /* @@ -295,4 +304,10 @@ static inline int static_call_text_reserved(void *start, void *end) #endif /* CONFIG_HAVE_STATIC_CALL */ +#define DEFINE_STATIC_CALL(name, _func) \ + __DEFINE_STATIC_CALL(name, _func, _func) + +#define DEFINE_STATIC_CALL_RET0(name, _func) \ + __DEFINE_STATIC_CALL(name, _func, __static_call_return0) + #endif /* _LINUX_STATIC_CALL_H */ diff --git a/include/linux/static_call_types.h b/include/linux/static_call_types.h index 89135bb35bf7..ae5662d368b9 100644 --- a/include/linux/static_call_types.h +++ b/include/linux/static_call_types.h @@ -4,11 +4,13 @@ #include <linux/types.h> #include <linux/stringify.h> +#include <linux/compiler.h> #define STATIC_CALL_KEY_PREFIX __SCK__ #define STATIC_CALL_KEY_PREFIX_STR __stringify(STATIC_CALL_KEY_PREFIX) #define STATIC_CALL_KEY_PREFIX_LEN (sizeof(STATIC_CALL_KEY_PREFIX_STR) - 1) #define STATIC_CALL_KEY(name) __PASTE(STATIC_CALL_KEY_PREFIX, name) +#define STATIC_CALL_KEY_STR(name) __stringify(STATIC_CALL_KEY(name)) #define STATIC_CALL_TRAMP_PREFIX __SCT__ #define STATIC_CALL_TRAMP_PREFIX_STR __stringify(STATIC_CALL_TRAMP_PREFIX) @@ -32,4 +34,52 @@ struct static_call_site { s32 key; }; +#define DECLARE_STATIC_CALL(name, func) \ + extern struct static_call_key STATIC_CALL_KEY(name); \ + extern typeof(func) STATIC_CALL_TRAMP(name); + +#ifdef CONFIG_HAVE_STATIC_CALL + +#define __raw_static_call(name) (&STATIC_CALL_TRAMP(name)) + +#ifdef CONFIG_HAVE_STATIC_CALL_INLINE + +/* + * __ADDRESSABLE() is used to ensure the key symbol doesn't get stripped from + * the symbol table so that objtool can reference it when it generates the + * .static_call_sites section. + */ +#define __STATIC_CALL_ADDRESSABLE(name) \ + __ADDRESSABLE(STATIC_CALL_KEY(name)) + +#define __static_call(name) \ +({ \ + __STATIC_CALL_ADDRESSABLE(name); \ + __raw_static_call(name); \ +}) + +#else /* !CONFIG_HAVE_STATIC_CALL_INLINE */ + +#define __STATIC_CALL_ADDRESSABLE(name) +#define __static_call(name) __raw_static_call(name) + +#endif /* CONFIG_HAVE_STATIC_CALL_INLINE */ + +#ifdef MODULE +#define __STATIC_CALL_MOD_ADDRESSABLE(name) +#define static_call_mod(name) __raw_static_call(name) +#else +#define __STATIC_CALL_MOD_ADDRESSABLE(name) __STATIC_CALL_ADDRESSABLE(name) +#define static_call_mod(name) __static_call(name) +#endif + +#define static_call(name) __static_call(name) + +#else + +#define static_call(name) \ + ((typeof(STATIC_CALL_TRAMP(name))*)(STATIC_CALL_KEY(name).func)) + +#endif /* CONFIG_HAVE_STATIC_CALL */ + #endif /* _STATIC_CALL_TYPES_H */ diff --git a/include/linux/topology.h b/include/linux/topology.h index ad03df1cc266..7634cd737061 100644 --- a/include/linux/topology.h +++ b/include/linux/topology.h @@ -48,6 +48,7 @@ int arch_update_cpu_topology(void); /* Conform to ACPI 2.0 SLIT distance definitions */ #define LOCAL_DISTANCE 10 #define REMOTE_DISTANCE 20 +#define DISTANCE_BITS 8 #ifndef node_distance #define node_distance(from,to) ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE) #endif diff --git a/init/Kconfig b/init/Kconfig index 17e955fdec97..096e1af5c586 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -524,7 +524,7 @@ config SCHED_THERMAL_PRESSURE i.e. put less load on throttled CPUs than on non/less throttled ones. This requires the architecture to implement - arch_set_thermal_pressure() and arch_get_thermal_pressure(). + arch_set_thermal_pressure() and arch_scale_thermal_pressure(). config BSD_PROCESS_ACCT bool "BSD Process Accounting" diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt index bf82259cff96..416017301660 100644 --- a/kernel/Kconfig.preempt +++ b/kernel/Kconfig.preempt @@ -40,6 +40,7 @@ config PREEMPT depends on !ARCH_NO_PREEMPT select PREEMPTION select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK + select PREEMPT_DYNAMIC if HAVE_PREEMPT_DYNAMIC help This option reduces the latency of the kernel by making all kernel code (that is not executing in a critical section) @@ -80,3 +81,21 @@ config PREEMPT_COUNT config PREEMPTION bool select PREEMPT_COUNT + +config PREEMPT_DYNAMIC + bool + help + This option allows to define the preemption model on the kernel + command line parameter and thus override the default preemption + model defined during compile time. + + The feature is primarily interesting for Linux distributions which + provide a pre-built kernel binary to reduce the number of kernel + flavors they offer while still offering different usecases. + + The runtime overhead is negligible with HAVE_STATIC_CALL_INLINE enabled + but if runtime patching is not available for the specific architecture + then the potential overhead should be considered. + + Interesting if you want the same pre-built kernel should be used for + both Server and Desktop workloads. diff --git a/kernel/entry/common.c b/kernel/entry/common.c index f9d491b17b78..8442e5c9cfa2 100644 --- a/kernel/entry/common.c +++ b/kernel/entry/common.c @@ -184,6 +184,10 @@ static unsigned long exit_to_user_mode_loop(struct pt_regs *regs, * enabled above. */ local_irq_disable_exit_to_user(); + + /* Check if any of the above work has queued a deferred wakeup */ + rcu_nocb_flush_deferred_wakeup(); + ti_work = READ_ONCE(current_thread_info()->flags); } @@ -197,6 +201,9 @@ static void exit_to_user_mode_prepare(struct pt_regs *regs) lockdep_assert_irqs_disabled(); + /* Flush pending rcuog wakeup before the last need_resched() check */ + rcu_nocb_flush_deferred_wakeup(); + if (unlikely(ti_work & EXIT_TO_USER_MODE_WORK)) ti_work = exit_to_user_mode_loop(regs, ti_work); @@ -385,6 +392,9 @@ void irqentry_exit_cond_resched(void) preempt_schedule_irq(); } } +#ifdef CONFIG_PREEMPT_DYNAMIC +DEFINE_STATIC_CALL(irqentry_exit_cond_resched, irqentry_exit_cond_resched); +#endif noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state) { @@ -411,8 +421,13 @@ noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state) } instrumentation_begin(); - if (IS_ENABLED(CONFIG_PREEMPTION)) + if (IS_ENABLED(CONFIG_PREEMPTION)) { +#ifdef CONFIG_PREEMT_DYNAMIC + static_call(irqentry_exit_cond_resched)(); +#else irqentry_exit_cond_resched(); +#endif + } /* Covers both tracing and lockdep */ trace_hardirqs_on(); instrumentation_end(); diff --git a/kernel/events/core.c b/kernel/events/core.c index c37401e3e5f7..5fe7d6346762 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1597,50 +1597,91 @@ static void perf_event_groups_init(struct perf_event_groups *groups) groups->index = 0; } +static inline struct cgroup *event_cgroup(const struct perf_event *event) +{ + struct cgroup *cgroup = NULL; + +#ifdef CONFIG_CGROUP_PERF + if (event->cgrp) + cgroup = event->cgrp->css.cgroup; +#endif + + return cgroup; +} + /* * Compare function for event groups; * * Implements complex key that first sorts by CPU and then by virtual index * which provides ordering when rotating groups for the same CPU. */ -static bool -perf_event_groups_less(struct perf_event *left, struct perf_event *right) +static __always_inline int +perf_event_groups_cmp(const int left_cpu, const struct cgroup *left_cgroup, + const u64 left_group_index, const struct perf_event *right) { - if (left->cpu < right->cpu) - return true; - if (left->cpu > right->cpu) - return false; + if (left_cpu < right->cpu) + return -1; + if (left_cpu > right->cpu) + return 1; #ifdef CONFIG_CGROUP_PERF - if (left->cgrp != right->cgrp) { - if (!left->cgrp || !left->cgrp->css.cgroup) { - /* - * Left has no cgroup but right does, no cgroups come - * first. - */ - return true; - } - if (!right->cgrp || !right->cgrp->css.cgroup) { - /* - * Right has no cgroup but left does, no cgroups come - * first. - */ - return false; - } - /* Two dissimilar cgroups, order by id. */ - if (left->cgrp->css.cgroup->kn->id < right->cgrp->css.cgroup->kn->id) - return true; + { + const struct cgroup *right_cgroup = event_cgroup(right); - return false; + if (left_cgroup != right_cgroup) { + if (!left_cgroup) { + /* + * Left has no cgroup but right does, no + * cgroups come first. + */ + return -1; + } + if (!right_cgroup) { + /* + * Right has no cgroup but left does, no + * cgroups come first. + */ + return 1; + } + /* Two dissimilar cgroups, order by id. */ + if (cgroup_id(left_cgroup) < cgroup_id(right_cgroup)) + return -1; + + return 1; + } } #endif - if (left->group_index < right->group_index) - return true; - if (left->group_index > right->group_index) - return false; + if (left_group_index < right->group_index) + return -1; + if (left_group_index > right->group_index) + return 1; - return false; + return 0; +} + +#define __node_2_pe(node) \ + rb_entry((node), struct perf_event, group_node) + +static inline bool __group_less(struct rb_node *a, const struct rb_node *b) +{ + struct perf_event *e = __node_2_pe(a); + return perf_event_groups_cmp(e->cpu, event_cgroup(e), e->group_index, + __node_2_pe(b)) < 0; +} + +struct __group_key { + int cpu; + struct cgroup *cgroup; +}; + +static inline int __group_cmp(const void *key, const struct rb_node *node) +{ + const struct __group_key *a = key; + const struct perf_event *b = __node_2_pe(node); + + /* partial/subtree match: @cpu, @cgroup; ignore: @group_index */ + return perf_event_groups_cmp(a->cpu, a->cgroup, b->group_index, b); } /* @@ -1652,27 +1693,9 @@ static void perf_event_groups_insert(struct perf_event_groups *groups, struct perf_event *event) { - struct perf_event *node_event; - struct rb_node *parent; - struct rb_node **node; - event->group_index = ++groups->index; - node = &groups->tree.rb_node; - parent = *node; - - while (*node) { - parent = *node; - node_event = container_of(*node, struct perf_event, group_node); - - if (perf_event_groups_less(event, node_event)) - node = &parent->rb_left; - else - node = &parent->rb_right; - } - - rb_link_node(&event->group_node, parent, node); - rb_insert_color(&event->group_node, &groups->tree); + rb_add(&event->group_node, &groups->tree, __group_less); } /* @@ -1720,45 +1743,17 @@ static struct perf_event * perf_event_groups_first(struct perf_event_groups *groups, int cpu, struct cgroup *cgrp) { - struct perf_event *node_event = NULL, *match = NULL; - struct rb_node *node = groups->tree.rb_node; -#ifdef CONFIG_CGROUP_PERF - u64 node_cgrp_id, cgrp_id = 0; - - if (cgrp) - cgrp_id = cgrp->kn->id; -#endif - - while (node) { - node_event = container_of(node, struct perf_event, group_node); - - if (cpu < node_event->cpu) { - node = node->rb_left; - continue; - } - if (cpu > node_event->cpu) { - node = node->rb_right; - continue; - } -#ifdef CONFIG_CGROUP_PERF - node_cgrp_id = 0; - if (node_event->cgrp && node_event->cgrp->css.cgroup) - node_cgrp_id = node_event->cgrp->css.cgroup->kn->id; + struct __group_key key = { + .cpu = cpu, + .cgroup = cgrp, + }; + struct rb_node *node; - if (cgrp_id < node_cgrp_id) { - node = node->rb_left; - continue; - } - if (cgrp_id > node_cgrp_id) { - node = node->rb_right; - continue; - } -#endif - match = node_event; - node = node->rb_left; - } + node = rb_find_first(&key, &groups->tree, __group_cmp); + if (node) + return __node_2_pe(node); - return match; + return NULL; } /* @@ -1767,27 +1762,17 @@ perf_event_groups_first(struct perf_event_groups *groups, int cpu, static struct perf_event * perf_event_groups_next(struct perf_event *event) { - struct perf_event *next; -#ifdef CONFIG_CGROUP_PERF - u64 curr_cgrp_id = 0; - u64 next_cgrp_id = 0; -#endif - - next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); - if (next == NULL || next->cpu != event->cpu) - return NULL; - -#ifdef CONFIG_CGROUP_PERF - if (event->cgrp && event->cgrp->css.cgroup) - curr_cgrp_id = event->cgrp->css.cgroup->kn->id; + struct __group_key key = { + .cpu = event->cpu, + .cgroup = event_cgroup(event), + }; + struct rb_node *next; - if (next->cgrp && next->cgrp->css.cgroup) - next_cgrp_id = next->cgrp->css.cgroup->kn->id; + next = rb_next_match(&key, &event->group_node, __group_cmp); + if (next) + return __node_2_pe(next); - if (curr_cgrp_id != next_cgrp_id) - return NULL; -#endif - return next; + return NULL; } /* diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index bf9edd8d75be..3ea7f8f92f1d 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -613,41 +613,56 @@ static void put_uprobe(struct uprobe *uprobe) } } -static int match_uprobe(struct uprobe *l, struct uprobe *r) +static __always_inline +int uprobe_cmp(const struct inode *l_inode, const loff_t l_offset, + const struct uprobe *r) { - if (l->inode < r->inode) + if (l_inode < r->inode) return -1; - if (l->inode > r->inode) + if (l_inode > r->inode) return 1; - if (l->offset < r->offset) + if (l_offset < r->offset) return -1; - if (l->offset > r->offset) + if (l_offset > r->offset) return 1; return 0; } +#define __node_2_uprobe(node) \ + rb_entry((node), struct uprobe, rb_node) + +struct __uprobe_key { + struct inode *inode; + loff_t offset; +}; + +static inline int __uprobe_cmp_key(const void *key, const struct rb_node *b) +{ + const struct __uprobe_key *a = key; + return uprobe_cmp(a->inode, a->offset, __node_2_uprobe(b)); +} + +static inline int __uprobe_cmp(struct rb_node *a, const struct rb_node *b) +{ + struct uprobe *u = __node_2_uprobe(a); + return uprobe_cmp(u->inode, u->offset, __node_2_uprobe(b)); +} + static struct uprobe *__find_uprobe(struct inode *inode, loff_t offset) { - struct uprobe u = { .inode = inode, .offset = offset }; - struct rb_node *n = uprobes_tree.rb_node; - struct uprobe *uprobe; - int match; + struct __uprobe_key key = { + .inode = inode, + .offset = offset, + }; + struct rb_node *node = rb_find(&key, &uprobes_tree, __uprobe_cmp_key); - while (n) { - uprobe = rb_entry(n, struct uprobe, rb_node); - match = match_uprobe(&u, uprobe); - if (!match) - return get_uprobe(uprobe); + if (node) + return get_uprobe(__node_2_uprobe(node)); - if (match < 0) - n = n->rb_left; - else - n = n->rb_right; - } return NULL; } @@ -668,32 +683,15 @@ static struct uprobe *find_uprobe(struct inode *inode, loff_t offset) static struct uprobe *__insert_uprobe(struct uprobe *uprobe) { - struct rb_node **p = &uprobes_tree.rb_node; - struct rb_node *parent = NULL; - struct uprobe *u; - int match; + struct rb_node *node; - while (*p) { - parent = *p; - u = rb_entry(parent, struct uprobe, rb_node); - match = match_uprobe(uprobe, u); - if (!match) - return get_uprobe(u); + node = rb_find_add(&uprobe->rb_node, &uprobes_tree, __uprobe_cmp); + if (node) + return get_uprobe(__node_2_uprobe(node)); - if (match < 0) - p = &parent->rb_left; - else - p = &parent->rb_right; - - } - - u = NULL; - rb_link_node(&uprobe->rb_node, parent, p); - rb_insert_color(&uprobe->rb_node, &uprobes_tree); /* get access + creation ref */ refcount_set(&uprobe->ref, 2); - - return u; + return NULL; } /* diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 47a6e0b8073d..03b21135313c 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -267,27 +267,18 @@ rt_mutex_waiter_equal(struct rt_mutex_waiter *left, return 1; } +#define __node_2_waiter(node) \ + rb_entry((node), struct rt_mutex_waiter, tree_entry) + +static inline bool __waiter_less(struct rb_node *a, const struct rb_node *b) +{ + return rt_mutex_waiter_less(__node_2_waiter(a), __node_2_waiter(b)); +} + static void rt_mutex_enqueue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter) { - struct rb_node **link = &lock->waiters.rb_root.rb_node; - struct rb_node *parent = NULL; - struct rt_mutex_waiter *entry; - bool leftmost = true; - - while (*link) { - parent = *link; - entry = rb_entry(parent, struct rt_mutex_waiter, tree_entry); - if (rt_mutex_waiter_less(waiter, entry)) { - link = &parent->rb_left; - } else { - link = &parent->rb_right; - leftmost = false; - } - } - - rb_link_node(&waiter->tree_entry, parent, link); - rb_insert_color_cached(&waiter->tree_entry, &lock->waiters, leftmost); + rb_add_cached(&waiter->tree_entry, &lock->waiters, __waiter_less); } static void @@ -300,27 +291,18 @@ rt_mutex_dequeue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter) RB_CLEAR_NODE(&waiter->tree_entry); } +#define __node_2_pi_waiter(node) \ + rb_entry((node), struct rt_mutex_waiter, pi_tree_entry) + +static inline bool __pi_waiter_less(struct rb_node *a, const struct rb_node *b) +{ + return rt_mutex_waiter_less(__node_2_pi_waiter(a), __node_2_pi_waiter(b)); +} + static void rt_mutex_enqueue_pi(struct task_struct *task, struct rt_mutex_waiter *waiter) { - struct rb_node **link = &task->pi_waiters.rb_root.rb_node; - struct rb_node *parent = NULL; - struct rt_mutex_waiter *entry; - bool leftmost = true; - - while (*link) { - parent = *link; - entry = rb_entry(parent, struct rt_mutex_waiter, pi_tree_entry); - if (rt_mutex_waiter_less(waiter, entry)) { - link = &parent->rb_left; - } else { - link = &parent->rb_right; - leftmost = false; - } - } - - rb_link_node(&waiter->pi_tree_entry, parent, link); - rb_insert_color_cached(&waiter->pi_tree_entry, &task->pi_waiters, leftmost); + rb_add_cached(&waiter->pi_tree_entry, &task->pi_waiters, __pi_waiter_less); } static void diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 0f4a6a3c057b..da6f5213fb74 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -649,7 +649,6 @@ static noinstr void rcu_eqs_enter(bool user) trace_rcu_dyntick(TPS("Start"), rdp->dynticks_nesting, 0, atomic_read(&rdp->dynticks)); WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !user && !is_idle_task(current)); rdp = this_cpu_ptr(&rcu_data); - do_nocb_deferred_wakeup(rdp); rcu_prepare_for_idle(); rcu_preempt_deferred_qs(current); @@ -683,6 +682,50 @@ void rcu_idle_enter(void) EXPORT_SYMBOL_GPL(rcu_idle_enter); #ifdef CONFIG_NO_HZ_FULL + +#if !defined(CONFIG_GENERIC_ENTRY) || !defined(CONFIG_KVM_XFER_TO_GUEST_WORK) +/* + * An empty function that will trigger a reschedule on + * IRQ tail once IRQs get re-enabled on userspace/guest resume. + */ +static void late_wakeup_func(struct irq_work *work) +{ +} + +static DEFINE_PER_CPU(struct irq_work, late_wakeup_work) = + IRQ_WORK_INIT(late_wakeup_func); + +/* + * If either: + * + * 1) the task is about to enter in guest mode and $ARCH doesn't support KVM generic work + * 2) the task is about to enter in user mode and $ARCH doesn't support generic entry. + * + * In these cases the late RCU wake ups aren't supported in the resched loops and our + * last resort is to fire a local irq_work that will trigger a reschedule once IRQs + * get re-enabled again. + */ +noinstr static void rcu_irq_work_resched(void) +{ + struct rcu_data *rdp = this_cpu_ptr(&rcu_data); + + if (IS_ENABLED(CONFIG_GENERIC_ENTRY) && !(current->flags & PF_VCPU)) + return; + + if (IS_ENABLED(CONFIG_KVM_XFER_TO_GUEST_WORK) && (current->flags & PF_VCPU)) + return; + + instrumentation_begin(); + if (do_nocb_deferred_wakeup(rdp) && need_resched()) { + irq_work_queue(this_cpu_ptr(&late_wakeup_work)); + } + instrumentation_end(); +} + +#else +static inline void rcu_irq_work_resched(void) { } +#endif + /** * rcu_user_enter - inform RCU that we are resuming userspace. * @@ -697,8 +740,16 @@ EXPORT_SYMBOL_GPL(rcu_idle_enter); noinstr void rcu_user_enter(void) { lockdep_assert_irqs_disabled(); + + /* + * Other than generic entry implementation, we may be past the last + * rescheduling opportunity in the entry code. Trigger a self IPI + * that will fire and reschedule once we resume in user/guest mode. + */ + rcu_irq_work_resched(); rcu_eqs_enter(true); } + #endif /* CONFIG_NO_HZ_FULL */ /** diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 5d359b9f9fec..71821d59d95c 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -435,7 +435,7 @@ static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp, static void __call_rcu_nocb_wake(struct rcu_data *rdp, bool was_empty, unsigned long flags); static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp); -static void do_nocb_deferred_wakeup(struct rcu_data *rdp); +static bool do_nocb_deferred_wakeup(struct rcu_data *rdp); static void rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp); static void rcu_spawn_cpu_nocb_kthread(int cpu); static void __init rcu_spawn_nocb_kthreads(void); diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 231a0c6cf03c..2d603771c7dc 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -1632,8 +1632,8 @@ bool rcu_is_nocb_cpu(int cpu) * Kick the GP kthread for this NOCB group. Caller holds ->nocb_lock * and this function releases it. */ -static void wake_nocb_gp(struct rcu_data *rdp, bool force, - unsigned long flags) +static bool wake_nocb_gp(struct rcu_data *rdp, bool force, + unsigned long flags) __releases(rdp->nocb_lock) { bool needwake = false; @@ -1644,7 +1644,7 @@ static void wake_nocb_gp(struct rcu_data *rdp, bool force, trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("AlreadyAwake")); rcu_nocb_unlock_irqrestore(rdp, flags); - return; + return false; } del_timer(&rdp->nocb_timer); rcu_nocb_unlock_irqrestore(rdp, flags); @@ -1657,6 +1657,8 @@ static void wake_nocb_gp(struct rcu_data *rdp, bool force, raw_spin_unlock_irqrestore(&rdp_gp->nocb_gp_lock, flags); if (needwake) wake_up_process(rdp_gp->nocb_gp_kthread); + + return needwake; } /* @@ -2251,20 +2253,23 @@ static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp) } /* Do a deferred wakeup of rcu_nocb_kthread(). */ -static void do_nocb_deferred_wakeup_common(struct rcu_data *rdp) +static bool do_nocb_deferred_wakeup_common(struct rcu_data *rdp) { unsigned long flags; int ndw; + int ret; rcu_nocb_lock_irqsave(rdp, flags); if (!rcu_nocb_need_deferred_wakeup(rdp)) { rcu_nocb_unlock_irqrestore(rdp, flags); - return; + return false; } ndw = READ_ONCE(rdp->nocb_defer_wakeup); WRITE_ONCE(rdp->nocb_defer_wakeup, RCU_NOCB_WAKE_NOT); - wake_nocb_gp(rdp, ndw == RCU_NOCB_WAKE_FORCE, flags); + ret = wake_nocb_gp(rdp, ndw == RCU_NOCB_WAKE_FORCE, flags); trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("DeferredWake")); + + return ret; } /* Do a deferred wakeup of rcu_nocb_kthread() from a timer handler. */ @@ -2280,11 +2285,18 @@ static void do_nocb_deferred_wakeup_timer(struct timer_list *t) * This means we do an inexact common-case check. Note that if * we miss, ->nocb_timer will eventually clean things up. */ -static void do_nocb_deferred_wakeup(struct rcu_data *rdp) +static bool do_nocb_deferred_wakeup(struct rcu_data *rdp) { if (rcu_nocb_need_deferred_wakeup(rdp)) - do_nocb_deferred_wakeup_common(rdp); + return do_nocb_deferred_wakeup_common(rdp); + return false; +} + +void rcu_nocb_flush_deferred_wakeup(void) +{ + do_nocb_deferred_wakeup(this_cpu_ptr(&rcu_data)); } +EXPORT_SYMBOL_GPL(rcu_nocb_flush_deferred_wakeup); static int rdp_offload_toggle(struct rcu_data *rdp, bool offload, unsigned long flags) @@ -2835,8 +2847,9 @@ static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp) return false; } -static void do_nocb_deferred_wakeup(struct rcu_data *rdp) +static bool do_nocb_deferred_wakeup(struct rcu_data *rdp) { + return false; } static void rcu_spawn_cpu_nocb_kthread(int cpu) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 22f6748c16f6..7f5ffc878411 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -355,8 +355,9 @@ static enum hrtimer_restart hrtick(struct hrtimer *timer) static void __hrtick_restart(struct rq *rq) { struct hrtimer *timer = &rq->hrtick_timer; + ktime_t time = rq->hrtick_time; - hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); + hrtimer_start(timer, time, HRTIMER_MODE_ABS_PINNED_HARD); } /* @@ -380,7 +381,6 @@ static void __hrtick_start(void *arg) void hrtick_start(struct rq *rq, u64 delay) { struct hrtimer *timer = &rq->hrtick_timer; - ktime_t time; s64 delta; /* @@ -388,9 +388,7 @@ void hrtick_start(struct rq *rq, u64 delay) * doesn't make sense and can cause timer DoS. */ delta = max_t(s64, delay, 10000LL); - time = ktime_add_ns(timer->base->get_time(), delta); - - hrtimer_set_expires(timer, time); + rq->hrtick_time = ktime_add_ns(timer->base->get_time(), delta); if (rq == this_rq()) __hrtick_restart(rq); @@ -4970,7 +4968,7 @@ static void __sched notrace __schedule(bool preempt) schedule_debug(prev, preempt); - if (sched_feat(HRTICK)) + if (sched_feat(HRTICK) || sched_feat(HRTICK_DL)) hrtick_clear(rq); local_irq_disable(); @@ -5264,6 +5262,12 @@ asmlinkage __visible void __sched notrace preempt_schedule(void) NOKPROBE_SYMBOL(preempt_schedule); EXPORT_SYMBOL(preempt_schedule); +#ifdef CONFIG_PREEMPT_DYNAMIC +DEFINE_STATIC_CALL(preempt_schedule, __preempt_schedule_func); +EXPORT_STATIC_CALL_TRAMP(preempt_schedule); +#endif + + /** * preempt_schedule_notrace - preempt_schedule called by tracing * @@ -5316,8 +5320,197 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void) } EXPORT_SYMBOL_GPL(preempt_schedule_notrace); +#ifdef CONFIG_PREEMPT_DYNAMIC +DEFINE_STATIC_CALL(preempt_schedule_notrace, __preempt_schedule_notrace_func); +EXPORT_STATIC_CALL_TRAMP(preempt_schedule_notrace); +#endif + #endif /* CONFIG_PREEMPTION */ +#ifdef CONFIG_PREEMPT_DYNAMIC + +#include <linux/entry-common.h> + +/* + * SC:cond_resched + * SC:might_resched + * SC:preempt_schedule + * SC:preempt_schedule_notrace + * SC:irqentry_exit_cond_resched + * + * + * NONE: + * cond_resched <- __cond_resched + * might_resched <- RET0 + * preempt_schedule <- NOP + * preempt_schedule_notrace <- NOP + * irqentry_exit_cond_resched <- NOP + * + * VOLUNTARY: + * cond_resched <- __cond_resched + * might_resched <- __cond_resched + * preempt_schedule <- NOP + * preempt_schedule_notrace <- NOP + * irqentry_exit_cond_resched <- NOP + * + * FULL: + * cond_resched <- RET0 + * might_resched <- RET0 + * preempt_schedule <- preempt_schedule + * preempt_schedule_notrace <- preempt_schedule_notrace + * irqentry_exit_cond_resched <- irqentry_exit_cond_resched + */ + +enum { + preempt_dynamic_none = 0, + preempt_dynamic_voluntary, + preempt_dynamic_full, +}; + +static int preempt_dynamic_mode = preempt_dynamic_full; + +static int sched_dynamic_mode(const char *str) +{ + if (!strcmp(str, "none")) + return 0; + + if (!strcmp(str, "voluntary")) + return 1; + + if (!strcmp(str, "full")) + return 2; + + return -1; +} + +static void sched_dynamic_update(int mode) +{ + /* + * Avoid {NONE,VOLUNTARY} -> FULL transitions from ever ending up in + * the ZERO state, which is invalid. + */ + static_call_update(cond_resched, __cond_resched); + static_call_update(might_resched, __cond_resched); + static_call_update(preempt_schedule, __preempt_schedule_func); + static_call_update(preempt_schedule_notrace, __preempt_schedule_notrace_func); + static_call_update(irqentry_exit_cond_resched, irqentry_exit_cond_resched); + + switch (mode) { + case preempt_dynamic_none: + static_call_update(cond_resched, __cond_resched); + static_call_update(might_resched, (typeof(&__cond_resched)) __static_call_return0); + static_call_update(preempt_schedule, (typeof(&preempt_schedule)) NULL); + static_call_update(preempt_schedule_notrace, (typeof(&preempt_schedule_notrace)) NULL); + static_call_update(irqentry_exit_cond_resched, (typeof(&irqentry_exit_cond_resched)) NULL); + pr_info("Dynamic Preempt: none\n"); + break; + + case preempt_dynamic_voluntary: + static_call_update(cond_resched, __cond_resched); + static_call_update(might_resched, __cond_resched); + static_call_update(preempt_schedule, (typeof(&preempt_schedule)) NULL); + static_call_update(preempt_schedule_notrace, (typeof(&preempt_schedule_notrace)) NULL); + static_call_update(irqentry_exit_cond_resched, (typeof(&irqentry_exit_cond_resched)) NULL); + pr_info("Dynamic Preempt: voluntary\n"); + break; + + case preempt_dynamic_full: + static_call_update(cond_resched, (typeof(&__cond_resched)) __static_call_return0); + static_call_update(might_resched, (typeof(&__cond_resched)) __static_call_return0); + static_call_update(preempt_schedule, __preempt_schedule_func); + static_call_update(preempt_schedule_notrace, __preempt_schedule_notrace_func); + static_call_update(irqentry_exit_cond_resched, irqentry_exit_cond_resched); + pr_info("Dynamic Preempt: full\n"); + break; + } + + preempt_dynamic_mode = mode; +} + +static int __init setup_preempt_mode(char *str) +{ + int mode = sched_dynamic_mode(str); + if (mode < 0) { + pr_warn("Dynamic Preempt: unsupported mode: %s\n", str); + return 1; + } + + sched_dynamic_update(mode); + return 0; +} +__setup("preempt=", setup_preempt_mode); + +#ifdef CONFIG_SCHED_DEBUG + +static ssize_t sched_dynamic_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + char buf[16]; + int mode; + + if (cnt > 15) + cnt = 15; + + if (copy_from_user(&buf, ubuf, cnt)) + return -EFAULT; + + buf[cnt] = 0; + mode = sched_dynamic_mode(strstrip(buf)); + if (mode < 0) + return mode; + + sched_dynamic_update(mode); + + *ppos += cnt; + + return cnt; +} + +static int sched_dynamic_show(struct seq_file *m, void *v) +{ + static const char * preempt_modes[] = { + "none", "voluntary", "full" + }; + int i; + + for (i = 0; i < ARRAY_SIZE(preempt_modes); i++) { + if (preempt_dynamic_mode == i) + seq_puts(m, "("); + seq_puts(m, preempt_modes[i]); + if (preempt_dynamic_mode == i) + seq_puts(m, ")"); + + seq_puts(m, " "); + } + + seq_puts(m, "\n"); + return 0; +} + +static int sched_dynamic_open(struct inode *inode, struct file *filp) +{ + return single_open(filp, sched_dynamic_show, NULL); +} + +static const struct file_operations sched_dynamic_fops = { + .open = sched_dynamic_open, + .write = sched_dynamic_write, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static __init int sched_init_debug_dynamic(void) +{ + debugfs_create_file("sched_preempt", 0644, NULL, NULL, &sched_dynamic_fops); + return 0; +} +late_initcall(sched_init_debug_dynamic); + +#endif /* CONFIG_SCHED_DEBUG */ +#endif /* CONFIG_PREEMPT_DYNAMIC */ + + /* * This is the entry point to schedule() from kernel preemption * off of irq context. @@ -5615,8 +5808,12 @@ SYSCALL_DEFINE1(nice, int, increment) * @p: the task in question. * * Return: The priority value as seen by users in /proc. - * RT tasks are offset by -200. Normal tasks are centered - * around 0, value goes from -16 to +15. + * + * sched policy return value kernel prio user prio/nice + * + * normal, batch, idle [0 ... 39] [100 ... 139] 0/[-20 ... 19] + * fifo, rr [-2 ... -100] [98 ... 0] [1 ... 99] + * deadline -101 -1 0 */ int task_prio(const struct task_struct *p) { @@ -5675,6 +5872,120 @@ struct task_struct *idle_task(int cpu) return cpu_rq(cpu)->idle; } +#ifdef CONFIG_SMP +/* + * This function computes an effective utilization for the given CPU, to be + * used for frequency selection given the linear relation: f = u * f_max. + * + * The scheduler tracks the following metrics: + * + * cpu_util_{cfs,rt,dl,irq}() + * cpu_bw_dl() + * + * Where the cfs,rt and dl util numbers are tracked with the same metric and + * synchronized windows and are thus directly comparable. + * + * The cfs,rt,dl utilization are the running times measured with rq->clock_task + * which excludes things like IRQ and steal-time. These latter are then accrued + * in the irq utilization. + * + * The DL bandwidth number otoh is not a measured metric but a value computed + * based on the task model parameters and gives the minimal utilization + * required to meet deadlines. + */ +unsigned long effective_cpu_util(int cpu, unsigned long util_cfs, + unsigned long max, enum cpu_util_type type, + struct task_struct *p) +{ + unsigned long dl_util, util, irq; + struct rq *rq = cpu_rq(cpu); + + if (!uclamp_is_used() && + type == FREQUENCY_UTIL && rt_rq_is_runnable(&rq->rt)) { + return max; + } + + /* + * Early check to see if IRQ/steal time saturates the CPU, can be + * because of inaccuracies in how we track these -- see + * update_irq_load_avg(). + */ + irq = cpu_util_irq(rq); + if (unlikely(irq >= max)) + return max; + + /* + * Because the time spend on RT/DL tasks is visible as 'lost' time to + * CFS tasks and we use the same metric to track the effective + * utilization (PELT windows are synchronized) we can directly add them + * to obtain the CPU's actual utilization. + * + * CFS and RT utilization can be boosted or capped, depending on + * utilization clamp constraints requested by currently RUNNABLE + * tasks. + * When there are no CFS RUNNABLE tasks, clamps are released and + * frequency will be gracefully reduced with the utilization decay. + */ + util = util_cfs + cpu_util_rt(rq); + if (type == FREQUENCY_UTIL) + util = uclamp_rq_util_with(rq, util, p); + + dl_util = cpu_util_dl(rq); + + /* + * For frequency selection we do not make cpu_util_dl() a permanent part + * of this sum because we want to use cpu_bw_dl() later on, but we need + * to check if the CFS+RT+DL sum is saturated (ie. no idle time) such + * that we select f_max when there is no idle time. + * + * NOTE: numerical errors or stop class might cause us to not quite hit + * saturation when we should -- something for later. + */ + if (util + dl_util >= max) + return max; + + /* + * OTOH, for energy computation we need the estimated running time, so + * include util_dl and ignore dl_bw. + */ + if (type == ENERGY_UTIL) + util += dl_util; + + /* + * There is still idle time; further improve the number by using the + * irq metric. Because IRQ/steal time is hidden from the task clock we + * need to scale the task numbers: + * + * max - irq + * U' = irq + --------- * U + * max + */ + util = scale_irq_capacity(util, irq, max); + util += irq; + + /* + * Bandwidth required by DEADLINE must always be granted while, for + * FAIR and RT, we use blocked utilization of IDLE CPUs as a mechanism + * to gracefully reduce the frequency when no tasks show up for longer + * periods of time. + * + * Ideally we would like to set bw_dl as min/guaranteed freq and util + + * bw_dl as requested freq. However, cpufreq is not yet ready for such + * an interface. So, we only do the latter for now. + */ + if (type == FREQUENCY_UTIL) + util += cpu_bw_dl(rq); + + return min(max, util); +} + +unsigned long sched_cpu_util(int cpu, unsigned long max) +{ + return effective_cpu_util(cpu, cpu_util_cfs(cpu_rq(cpu)), max, + ENERGY_UTIL, NULL); +} +#endif /* CONFIG_SMP */ + /** * find_process_by_pid - find a process with a matching PID value. * @pid: the pid in question. @@ -5796,11 +6107,10 @@ recheck: /* * Valid priorities for SCHED_FIFO and SCHED_RR are - * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL, + * 1..MAX_RT_PRIO-1, valid priority for SCHED_NORMAL, * SCHED_BATCH and SCHED_IDLE is 0. */ - if ((p->mm && attr->sched_priority > MAX_USER_RT_PRIO-1) || - (!p->mm && attr->sched_priority > MAX_RT_PRIO-1)) + if (attr->sched_priority > MAX_RT_PRIO-1) return -EINVAL; if ((dl_policy(policy) && !__checkparam_dl(attr)) || (rt_policy(policy) != (attr->sched_priority != 0))) @@ -6667,17 +6977,27 @@ SYSCALL_DEFINE0(sched_yield) return 0; } -#ifndef CONFIG_PREEMPTION -int __sched _cond_resched(void) +#if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) +int __sched __cond_resched(void) { if (should_resched(0)) { preempt_schedule_common(); return 1; } +#ifndef CONFIG_PREEMPT_RCU rcu_all_qs(); +#endif return 0; } -EXPORT_SYMBOL(_cond_resched); +EXPORT_SYMBOL(__cond_resched); +#endif + +#ifdef CONFIG_PREEMPT_DYNAMIC +DEFINE_STATIC_CALL_RET0(cond_resched, __cond_resched); +EXPORT_STATIC_CALL_TRAMP(cond_resched); + +DEFINE_STATIC_CALL_RET0(might_resched, __cond_resched); +EXPORT_STATIC_CALL_TRAMP(might_resched); #endif /* @@ -6868,7 +7188,7 @@ SYSCALL_DEFINE1(sched_get_priority_max, int, policy) switch (policy) { case SCHED_FIFO: case SCHED_RR: - ret = MAX_USER_RT_PRIO-1; + ret = MAX_RT_PRIO-1; break; case SCHED_DEADLINE: case SCHED_NORMAL: @@ -7508,6 +7828,12 @@ int sched_cpu_deactivate(unsigned int cpu) struct rq_flags rf; int ret; + /* + * Remove CPU from nohz.idle_cpus_mask to prevent participating in + * load balancing when not active + */ + nohz_balance_exit_idle(rq); + set_cpu_active(cpu, false); /* @@ -7652,7 +7978,6 @@ int sched_cpu_dying(unsigned int cpu) calc_load_migrate(rq); update_max_interval(); - nohz_balance_exit_idle(rq); hrtick_clear(rq); return 0; } diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index 6931f0cdeb80..41e498b0008a 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -171,112 +171,6 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy, return cpufreq_driver_resolve_freq(policy, freq); } -/* - * This function computes an effective utilization for the given CPU, to be - * used for frequency selection given the linear relation: f = u * f_max. - * - * The scheduler tracks the following metrics: - * - * cpu_util_{cfs,rt,dl,irq}() - * cpu_bw_dl() - * - * Where the cfs,rt and dl util numbers are tracked with the same metric and - * synchronized windows and are thus directly comparable. - * - * The cfs,rt,dl utilization are the running times measured with rq->clock_task - * which excludes things like IRQ and steal-time. These latter are then accrued - * in the irq utilization. - * - * The DL bandwidth number otoh is not a measured metric but a value computed - * based on the task model parameters and gives the minimal utilization - * required to meet deadlines. - */ -unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs, - unsigned long max, enum schedutil_type type, - struct task_struct *p) -{ - unsigned long dl_util, util, irq; - struct rq *rq = cpu_rq(cpu); - - if (!uclamp_is_used() && - type == FREQUENCY_UTIL && rt_rq_is_runnable(&rq->rt)) { - return max; - } - - /* - * Early check to see if IRQ/steal time saturates the CPU, can be - * because of inaccuracies in how we track these -- see - * update_irq_load_avg(). - */ - irq = cpu_util_irq(rq); - if (unlikely(irq >= max)) - return max; - - /* - * Because the time spend on RT/DL tasks is visible as 'lost' time to - * CFS tasks and we use the same metric to track the effective - * utilization (PELT windows are synchronized) we can directly add them - * to obtain the CPU's actual utilization. - * - * CFS and RT utilization can be boosted or capped, depending on - * utilization clamp constraints requested by currently RUNNABLE - * tasks. - * When there are no CFS RUNNABLE tasks, clamps are released and - * frequency will be gracefully reduced with the utilization decay. - */ - util = util_cfs + cpu_util_rt(rq); - if (type == FREQUENCY_UTIL) - util = uclamp_rq_util_with(rq, util, p); - - dl_util = cpu_util_dl(rq); - - /* - * For frequency selection we do not make cpu_util_dl() a permanent part - * of this sum because we want to use cpu_bw_dl() later on, but we need - * to check if the CFS+RT+DL sum is saturated (ie. no idle time) such - * that we select f_max when there is no idle time. - * - * NOTE: numerical errors or stop class might cause us to not quite hit - * saturation when we should -- something for later. - */ - if (util + dl_util >= max) - return max; - - /* - * OTOH, for energy computation we need the estimated running time, so - * include util_dl and ignore dl_bw. - */ - if (type == ENERGY_UTIL) - util += dl_util; - - /* - * There is still idle time; further improve the number by using the - * irq metric. Because IRQ/steal time is hidden from the task clock we - * need to scale the task numbers: - * - * max - irq - * U' = irq + --------- * U - * max - */ - util = scale_irq_capacity(util, irq, max); - util += irq; - - /* - * Bandwidth required by DEADLINE must always be granted while, for - * FAIR and RT, we use blocked utilization of IDLE CPUs as a mechanism - * to gracefully reduce the frequency when no tasks show up for longer - * periods of time. - * - * Ideally we would like to set bw_dl as min/guaranteed freq and util + - * bw_dl as requested freq. However, cpufreq is not yet ready for such - * an interface. So, we only do the latter for now. - */ - if (type == FREQUENCY_UTIL) - util += cpu_bw_dl(rq); - - return min(max, util); -} - static void sugov_get_util(struct sugov_cpu *sg_cpu) { struct rq *rq = cpu_rq(sg_cpu->cpu); @@ -284,7 +178,7 @@ static void sugov_get_util(struct sugov_cpu *sg_cpu) sg_cpu->max = max; sg_cpu->bw_dl = cpu_bw_dl(rq); - sg_cpu->util = schedutil_cpu_util(sg_cpu->cpu, cpu_util_cfs(rq), max, + sg_cpu->util = effective_cpu_util(sg_cpu->cpu, cpu_util_cfs(rq), max, FREQUENCY_UTIL, NULL); } diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 75686c6d4436..aac3539aa0fe 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -517,58 +517,44 @@ static void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) update_dl_migration(dl_rq); } +#define __node_2_pdl(node) \ + rb_entry((node), struct task_struct, pushable_dl_tasks) + +static inline bool __pushable_less(struct rb_node *a, const struct rb_node *b) +{ + return dl_entity_preempt(&__node_2_pdl(a)->dl, &__node_2_pdl(b)->dl); +} + /* * The list of pushable -deadline task is not a plist, like in * sched_rt.c, it is an rb-tree with tasks ordered by deadline. */ static void enqueue_pushable_dl_task(struct rq *rq, struct task_struct *p) { - struct dl_rq *dl_rq = &rq->dl; - struct rb_node **link = &dl_rq->pushable_dl_tasks_root.rb_root.rb_node; - struct rb_node *parent = NULL; - struct task_struct *entry; - bool leftmost = true; + struct rb_node *leftmost; BUG_ON(!RB_EMPTY_NODE(&p->pushable_dl_tasks)); - while (*link) { - parent = *link; - entry = rb_entry(parent, struct task_struct, - pushable_dl_tasks); - if (dl_entity_preempt(&p->dl, &entry->dl)) - link = &parent->rb_left; - else { - link = &parent->rb_right; - leftmost = false; - } - } - + leftmost = rb_add_cached(&p->pushable_dl_tasks, + &rq->dl.pushable_dl_tasks_root, + __pushable_less); if (leftmost) - dl_rq->earliest_dl.next = p->dl.deadline; - - rb_link_node(&p->pushable_dl_tasks, parent, link); - rb_insert_color_cached(&p->pushable_dl_tasks, - &dl_rq->pushable_dl_tasks_root, leftmost); + rq->dl.earliest_dl.next = p->dl.deadline; } static void dequeue_pushable_dl_task(struct rq *rq, struct task_struct *p) { struct dl_rq *dl_rq = &rq->dl; + struct rb_root_cached *root = &dl_rq->pushable_dl_tasks_root; + struct rb_node *leftmost; if (RB_EMPTY_NODE(&p->pushable_dl_tasks)) return; - if (dl_rq->pushable_dl_tasks_root.rb_leftmost == &p->pushable_dl_tasks) { - struct rb_node *next_node; - - next_node = rb_next(&p->pushable_dl_tasks); - if (next_node) { - dl_rq->earliest_dl.next = rb_entry(next_node, - struct task_struct, pushable_dl_tasks)->dl.deadline; - } - } + leftmost = rb_erase_cached(&p->pushable_dl_tasks, root); + if (leftmost) + dl_rq->earliest_dl.next = __node_2_pdl(leftmost)->dl.deadline; - rb_erase_cached(&p->pushable_dl_tasks, &dl_rq->pushable_dl_tasks_root); RB_CLEAR_NODE(&p->pushable_dl_tasks); } @@ -1478,29 +1464,21 @@ void dec_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) dec_dl_migration(dl_se, dl_rq); } +#define __node_2_dle(node) \ + rb_entry((node), struct sched_dl_entity, rb_node) + +static inline bool __dl_less(struct rb_node *a, const struct rb_node *b) +{ + return dl_time_before(__node_2_dle(a)->deadline, __node_2_dle(b)->deadline); +} + static void __enqueue_dl_entity(struct sched_dl_entity *dl_se) { struct dl_rq *dl_rq = dl_rq_of_se(dl_se); - struct rb_node **link = &dl_rq->root.rb_root.rb_node; - struct rb_node *parent = NULL; - struct sched_dl_entity *entry; - int leftmost = 1; BUG_ON(!RB_EMPTY_NODE(&dl_se->rb_node)); - while (*link) { - parent = *link; - entry = rb_entry(parent, struct sched_dl_entity, rb_node); - if (dl_time_before(dl_se->deadline, entry->deadline)) - link = &parent->rb_left; - else { - link = &parent->rb_right; - leftmost = 0; - } - } - - rb_link_node(&dl_se->rb_node, parent, link); - rb_insert_color_cached(&dl_se->rb_node, &dl_rq->root, leftmost); + rb_add_cached(&dl_se->rb_node, &dl_rq->root, __dl_less); inc_dl_tasks(dl_se, dl_rq); } @@ -1513,6 +1491,7 @@ static void __dequeue_dl_entity(struct sched_dl_entity *dl_se) return; rb_erase_cached(&dl_se->rb_node, &dl_rq->root); + RB_CLEAR_NODE(&dl_se->rb_node); dec_dl_tasks(dl_se, dl_rq); @@ -1853,7 +1832,7 @@ static void set_next_task_dl(struct rq *rq, struct task_struct *p, bool first) if (!first) return; - if (hrtick_enabled(rq)) + if (hrtick_enabled_dl(rq)) start_hrtick_dl(rq, p); if (rq->curr->sched_class != &dl_sched_class) @@ -1916,7 +1895,7 @@ static void task_tick_dl(struct rq *rq, struct task_struct *p, int queued) * not being the leftmost task anymore. In that case NEED_RESCHED will * be set and schedule() will start a new hrtick for the next task. */ - if (hrtick_enabled(rq) && queued && p->dl.runtime > 0 && + if (hrtick_enabled_dl(rq) && queued && p->dl.runtime > 0 && is_leftmost(p, &rq->dl)) start_hrtick_dl(rq, p); } @@ -2409,9 +2388,13 @@ void dl_add_task_root_domain(struct task_struct *p) struct rq *rq; struct dl_bw *dl_b; - rq = task_rq_lock(p, &rf); - if (!dl_task(p)) - goto unlock; + raw_spin_lock_irqsave(&p->pi_lock, rf.flags); + if (!dl_task(p)) { + raw_spin_unlock_irqrestore(&p->pi_lock, rf.flags); + return; + } + + rq = __task_rq_lock(p, &rf); dl_b = &rq->rd->dl_bw; raw_spin_lock(&dl_b->lock); @@ -2420,7 +2403,6 @@ void dl_add_task_root_domain(struct task_struct *p) raw_spin_unlock(&dl_b->lock); -unlock: task_rq_unlock(rq, p, &rf); } @@ -2514,7 +2496,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p) static void prio_changed_dl(struct rq *rq, struct task_struct *p, int oldprio) { - if (task_on_rq_queued(p) || rq->curr == p) { + if (task_on_rq_queued(p) || task_current(rq, p)) { #ifdef CONFIG_SMP /* * This might be too much, but unfortunately diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 2357921580f9..486f403a778b 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -486,7 +486,7 @@ static char *task_group_path(struct task_group *tg) static void print_task(struct seq_file *m, struct rq *rq, struct task_struct *p) { - if (rq->curr == p) + if (task_current(rq, p)) SEQ_printf(m, ">R"); else SEQ_printf(m, " %c", task_state_to_char(p)); diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 04a3ce20da67..8a8bd7b13634 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -531,12 +531,15 @@ static inline u64 min_vruntime(u64 min_vruntime, u64 vruntime) return min_vruntime; } -static inline int entity_before(struct sched_entity *a, +static inline bool entity_before(struct sched_entity *a, struct sched_entity *b) { return (s64)(a->vruntime - b->vruntime) < 0; } +#define __node_2_se(node) \ + rb_entry((node), struct sched_entity, run_node) + static void update_min_vruntime(struct cfs_rq *cfs_rq) { struct sched_entity *curr = cfs_rq->curr; @@ -552,8 +555,7 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq) } if (leftmost) { /* non-empty tree */ - struct sched_entity *se; - se = rb_entry(leftmost, struct sched_entity, run_node); + struct sched_entity *se = __node_2_se(leftmost); if (!curr) vruntime = se->vruntime; @@ -569,37 +571,17 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq) #endif } +static inline bool __entity_less(struct rb_node *a, const struct rb_node *b) +{ + return entity_before(__node_2_se(a), __node_2_se(b)); +} + /* * Enqueue an entity into the rb-tree: */ static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) { - struct rb_node **link = &cfs_rq->tasks_timeline.rb_root.rb_node; - struct rb_node *parent = NULL; - struct sched_entity *entry; - bool leftmost = true; - - /* - * Find the right place in the rbtree: - */ - while (*link) { - parent = *link; - entry = rb_entry(parent, struct sched_entity, run_node); - /* - * We dont care about collisions. Nodes with - * the same key stay together. - */ - if (entity_before(se, entry)) { - link = &parent->rb_left; - } else { - link = &parent->rb_right; - leftmost = false; - } - } - - rb_link_node(&se->run_node, parent, link); - rb_insert_color_cached(&se->run_node, - &cfs_rq->tasks_timeline, leftmost); + rb_add_cached(&se->run_node, &cfs_rq->tasks_timeline, __entity_less); } static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) @@ -614,7 +596,7 @@ struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq) if (!left) return NULL; - return rb_entry(left, struct sched_entity, run_node); + return __node_2_se(left); } static struct sched_entity *__pick_next_entity(struct sched_entity *se) @@ -624,7 +606,7 @@ static struct sched_entity *__pick_next_entity(struct sched_entity *se) if (!next) return NULL; - return rb_entry(next, struct sched_entity, run_node); + return __node_2_se(next); } #ifdef CONFIG_SCHED_DEBUG @@ -635,7 +617,7 @@ struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq) if (!last) return NULL; - return rb_entry(last, struct sched_entity, run_node); + return __node_2_se(last); } /************************************************************** @@ -3943,6 +3925,22 @@ static inline void util_est_enqueue(struct cfs_rq *cfs_rq, trace_sched_util_est_cfs_tp(cfs_rq); } +static inline void util_est_dequeue(struct cfs_rq *cfs_rq, + struct task_struct *p) +{ + unsigned int enqueued; + + if (!sched_feat(UTIL_EST)) + return; + + /* Update root cfs_rq's estimated utilization */ + enqueued = cfs_rq->avg.util_est.enqueued; + enqueued -= min_t(unsigned int, enqueued, _task_util_est(p)); + WRITE_ONCE(cfs_rq->avg.util_est.enqueued, enqueued); + + trace_sched_util_est_cfs_tp(cfs_rq); +} + /* * Check if a (signed) value is within a specified (unsigned) margin, * based on the observation that: @@ -3956,23 +3954,16 @@ static inline bool within_margin(int value, int margin) return ((unsigned int)(value + margin - 1) < (2 * margin - 1)); } -static void -util_est_dequeue(struct cfs_rq *cfs_rq, struct task_struct *p, bool task_sleep) +static inline void util_est_update(struct cfs_rq *cfs_rq, + struct task_struct *p, + bool task_sleep) { long last_ewma_diff; struct util_est ue; - int cpu; if (!sched_feat(UTIL_EST)) return; - /* Update root cfs_rq's estimated utilization */ - ue.enqueued = cfs_rq->avg.util_est.enqueued; - ue.enqueued -= min_t(unsigned int, ue.enqueued, _task_util_est(p)); - WRITE_ONCE(cfs_rq->avg.util_est.enqueued, ue.enqueued); - - trace_sched_util_est_cfs_tp(cfs_rq); - /* * Skip update of task's estimated utilization when the task has not * yet completed an activation, e.g. being migrated. @@ -4012,8 +4003,7 @@ util_est_dequeue(struct cfs_rq *cfs_rq, struct task_struct *p, bool task_sleep) * To avoid overestimation of actual task utilization, skip updates if * we cannot grant there is idle time in this CPU. */ - cpu = cpu_of(rq_of(cfs_rq)); - if (task_util(p) > capacity_orig_of(cpu)) + if (task_util(p) > capacity_orig_of(cpu_of(rq_of(cfs_rq)))) return; /* @@ -4052,7 +4042,7 @@ static inline void update_misfit_status(struct task_struct *p, struct rq *rq) if (!static_branch_unlikely(&sched_asym_cpucapacity)) return; - if (!p) { + if (!p || p->nr_cpus_allowed == 1) { rq->misfit_task_load = 0; return; } @@ -4096,8 +4086,11 @@ static inline void util_est_enqueue(struct cfs_rq *cfs_rq, struct task_struct *p) {} static inline void -util_est_dequeue(struct cfs_rq *cfs_rq, struct task_struct *p, - bool task_sleep) {} +util_est_dequeue(struct cfs_rq *cfs_rq, struct task_struct *p) {} + +static inline void +util_est_update(struct cfs_rq *cfs_rq, struct task_struct *p, + bool task_sleep) {} static inline void update_misfit_status(struct task_struct *p, struct rq *rq) {} #endif /* CONFIG_SMP */ @@ -5419,7 +5412,7 @@ static void hrtick_start_fair(struct rq *rq, struct task_struct *p) s64 delta = slice - ran; if (delta < 0) { - if (rq->curr == p) + if (task_current(rq, p)) resched_curr(rq); return; } @@ -5436,7 +5429,7 @@ static void hrtick_update(struct rq *rq) { struct task_struct *curr = rq->curr; - if (!hrtick_enabled(rq) || curr->sched_class != &fair_sched_class) + if (!hrtick_enabled_fair(rq) || curr->sched_class != &fair_sched_class) return; if (cfs_rq_of(&curr->se)->nr_running < sched_nr_latency) @@ -5609,6 +5602,8 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) int idle_h_nr_running = task_has_idle_policy(p); bool was_sched_idle = sched_idle_rq(rq); + util_est_dequeue(&rq->cfs, p); + for_each_sched_entity(se) { cfs_rq = cfs_rq_of(se); dequeue_entity(cfs_rq, se, flags); @@ -5659,7 +5654,7 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) rq->next_balance = jiffies; dequeue_throttle: - util_est_dequeue(&rq->cfs, p, task_sleep); + util_est_update(&rq->cfs, p, task_sleep); hrtick_update(rq); } @@ -6006,6 +6001,14 @@ static inline int find_idlest_cpu(struct sched_domain *sd, struct task_struct *p return new_cpu; } +static inline int __select_idle_cpu(int cpu) +{ + if (available_idle_cpu(cpu) || sched_idle_cpu(cpu)) + return cpu; + + return -1; +} + #ifdef CONFIG_SCHED_SMT DEFINE_STATIC_KEY_FALSE(sched_smt_present); EXPORT_SYMBOL_GPL(sched_smt_present); @@ -6064,74 +6067,51 @@ unlock: * there are no idle cores left in the system; tracked through * sd_llc->shared->has_idle_cores and enabled through update_idle_core() above. */ -static int select_idle_core(struct task_struct *p, struct sched_domain *sd, int target) +static int select_idle_core(struct task_struct *p, int core, struct cpumask *cpus, int *idle_cpu) { - struct cpumask *cpus = this_cpu_cpumask_var_ptr(select_idle_mask); - int core, cpu; + bool idle = true; + int cpu; if (!static_branch_likely(&sched_smt_present)) - return -1; + return __select_idle_cpu(core); - if (!test_idle_cores(target, false)) - return -1; - - cpumask_and(cpus, sched_domain_span(sd), p->cpus_ptr); - - for_each_cpu_wrap(core, cpus, target) { - bool idle = true; - - for_each_cpu(cpu, cpu_smt_mask(core)) { - if (!available_idle_cpu(cpu)) { - idle = false; - break; + for_each_cpu(cpu, cpu_smt_mask(core)) { + if (!available_idle_cpu(cpu)) { + idle = false; + if (*idle_cpu == -1) { + if (sched_idle_cpu(cpu) && cpumask_test_cpu(cpu, p->cpus_ptr)) { + *idle_cpu = cpu; + break; + } + continue; } + break; } - - if (idle) - return core; - - cpumask_andnot(cpus, cpus, cpu_smt_mask(core)); + if (*idle_cpu == -1 && cpumask_test_cpu(cpu, p->cpus_ptr)) + *idle_cpu = cpu; } - /* - * Failed to find an idle core; stop looking for one. - */ - set_idle_cores(target, 0); + if (idle) + return core; + cpumask_andnot(cpus, cpus, cpu_smt_mask(core)); return -1; } -/* - * Scan the local SMT mask for idle CPUs. - */ -static int select_idle_smt(struct task_struct *p, struct sched_domain *sd, int target) -{ - int cpu; - - if (!static_branch_likely(&sched_smt_present)) - return -1; - - for_each_cpu(cpu, cpu_smt_mask(target)) { - if (!cpumask_test_cpu(cpu, p->cpus_ptr) || - !cpumask_test_cpu(cpu, sched_domain_span(sd))) - continue; - if (available_idle_cpu(cpu) || sched_idle_cpu(cpu)) - return cpu; - } +#else /* CONFIG_SCHED_SMT */ - return -1; +static inline void set_idle_cores(int cpu, int val) +{ } -#else /* CONFIG_SCHED_SMT */ - -static inline int select_idle_core(struct task_struct *p, struct sched_domain *sd, int target) +static inline bool test_idle_cores(int cpu, bool def) { - return -1; + return def; } -static inline int select_idle_smt(struct task_struct *p, struct sched_domain *sd, int target) +static inline int select_idle_core(struct task_struct *p, int core, struct cpumask *cpus, int *idle_cpu) { - return -1; + return __select_idle_cpu(core); } #endif /* CONFIG_SCHED_SMT */ @@ -6144,49 +6124,61 @@ static inline int select_idle_smt(struct task_struct *p, struct sched_domain *sd static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int target) { struct cpumask *cpus = this_cpu_cpumask_var_ptr(select_idle_mask); + int i, cpu, idle_cpu = -1, nr = INT_MAX; + bool smt = test_idle_cores(target, false); + int this = smp_processor_id(); struct sched_domain *this_sd; - u64 avg_cost, avg_idle; u64 time; - int this = smp_processor_id(); - int cpu, nr = INT_MAX; this_sd = rcu_dereference(*this_cpu_ptr(&sd_llc)); if (!this_sd) return -1; - /* - * Due to large variance we need a large fuzz factor; hackbench in - * particularly is sensitive here. - */ - avg_idle = this_rq()->avg_idle / 512; - avg_cost = this_sd->avg_scan_cost + 1; + cpumask_and(cpus, sched_domain_span(sd), p->cpus_ptr); - if (sched_feat(SIS_AVG_CPU) && avg_idle < avg_cost) - return -1; + if (sched_feat(SIS_PROP) && !smt) { + u64 avg_cost, avg_idle, span_avg; + + /* + * Due to large variance we need a large fuzz factor; + * hackbench in particularly is sensitive here. + */ + avg_idle = this_rq()->avg_idle / 512; + avg_cost = this_sd->avg_scan_cost + 1; - if (sched_feat(SIS_PROP)) { - u64 span_avg = sd->span_weight * avg_idle; + span_avg = sd->span_weight * avg_idle; if (span_avg > 4*avg_cost) nr = div_u64(span_avg, avg_cost); else nr = 4; - } - - time = cpu_clock(this); - cpumask_and(cpus, sched_domain_span(sd), p->cpus_ptr); + time = cpu_clock(this); + } for_each_cpu_wrap(cpu, cpus, target) { - if (!--nr) - return -1; - if (available_idle_cpu(cpu) || sched_idle_cpu(cpu)) - break; + if (smt) { + i = select_idle_core(p, cpu, cpus, &idle_cpu); + if ((unsigned int)i < nr_cpumask_bits) + return i; + + } else { + if (!--nr) + return -1; + idle_cpu = __select_idle_cpu(cpu); + if ((unsigned int)idle_cpu < nr_cpumask_bits) + break; + } } - time = cpu_clock(this) - time; - update_avg(&this_sd->avg_scan_cost, time); + if (smt) + set_idle_cores(this, false); - return cpu; + if (sched_feat(SIS_PROP) && !smt) { + time = cpu_clock(this) - time; + update_avg(&this_sd->avg_scan_cost, time); + } + + return idle_cpu; } /* @@ -6315,18 +6307,10 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) if (!sd) return target; - i = select_idle_core(p, sd, target); - if ((unsigned)i < nr_cpumask_bits) - return i; - i = select_idle_cpu(p, sd, target); if ((unsigned)i < nr_cpumask_bits) return i; - i = select_idle_smt(p, sd, target); - if ((unsigned)i < nr_cpumask_bits) - return i; - return target; } @@ -6543,7 +6527,7 @@ compute_energy(struct task_struct *p, int dst_cpu, struct perf_domain *pd) * is already enough to scale the EM reported power * consumption at the (eventually clamped) cpu_capacity. */ - sum_util += schedutil_cpu_util(cpu, util_cfs, cpu_cap, + sum_util += effective_cpu_util(cpu, util_cfs, cpu_cap, ENERGY_UTIL, NULL); /* @@ -6553,7 +6537,7 @@ compute_energy(struct task_struct *p, int dst_cpu, struct perf_domain *pd) * NOTE: in case RT tasks are running, by default the * FREQUENCY_UTIL's utilization can be max OPP. */ - cpu_util = schedutil_cpu_util(cpu, util_cfs, cpu_cap, + cpu_util = effective_cpu_util(cpu, util_cfs, cpu_cap, FREQUENCY_UTIL, tsk); max_util = max(max_util, cpu_util); } @@ -6651,7 +6635,7 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) * IOW, placing the task there would make the CPU * overutilized. Take uclamp into account to see how * much capacity we can get out of the CPU; this is - * aligned with schedutil_cpu_util(). + * aligned with sched_cpu_util(). */ util = uclamp_rq_util_with(cpu_rq(cpu), util, p); if (!fits_capacity(util, cpu_cap)) @@ -7132,7 +7116,7 @@ done: __maybe_unused; list_move(&p->se.group_node, &rq->cfs_tasks); #endif - if (hrtick_enabled(rq)) + if (hrtick_enabled_fair(rq)) hrtick_start_fair(rq, p); update_misfit_status(p, rq); @@ -9389,8 +9373,11 @@ static struct rq *find_busiest_queue(struct lb_env *env, if (rt > env->fbq_type) continue; - capacity = capacity_of(i); nr_running = rq->cfs.h_nr_running; + if (!nr_running) + continue; + + capacity = capacity_of(i); /* * For ASYM_CPUCAPACITY domains, don't pick a CPU that could @@ -9496,13 +9483,32 @@ asym_active_balance(struct lb_env *env) } static inline bool -voluntary_active_balance(struct lb_env *env) +imbalanced_active_balance(struct lb_env *env) +{ + struct sched_domain *sd = env->sd; + + /* + * The imbalanced case includes the case of pinned tasks preventing a fair + * distribution of the load on the system but also the even distribution of the + * threads on a system with spare capacity + */ + if ((env->migration_type == migrate_task) && + (sd->nr_balance_failed > sd->cache_nice_tries+2)) + return 1; + + return 0; +} + +static int need_active_balance(struct lb_env *env) { struct sched_domain *sd = env->sd; if (asym_active_balance(env)) return 1; + if (imbalanced_active_balance(env)) + return 1; + /* * The dst_cpu is idle and the src_cpu CPU has only 1 CFS task. * It's worth migrating the task if the src_cpu's capacity is reduced @@ -9522,16 +9528,6 @@ voluntary_active_balance(struct lb_env *env) return 0; } -static int need_active_balance(struct lb_env *env) -{ - struct sched_domain *sd = env->sd; - - if (voluntary_active_balance(env)) - return 1; - - return unlikely(sd->nr_balance_failed > sd->cache_nice_tries+2); -} - static int active_load_balance_cpu_stop(void *data); static int should_we_balance(struct lb_env *env) @@ -9623,6 +9619,8 @@ redo: env.src_rq = busiest; ld_moved = 0; + /* Clear this flag as soon as we find a pullable task */ + env.flags |= LBF_ALL_PINNED; if (busiest->nr_running > 1) { /* * Attempt to move tasks. If find_busiest_group has found @@ -9630,7 +9628,6 @@ redo: * still unbalanced. ld_moved simply stays zero, so it is * correctly treated as an imbalance. */ - env.flags |= LBF_ALL_PINNED; env.loop_max = min(sysctl_sched_nr_migrate, busiest->nr_running); more_balance: @@ -9756,10 +9753,12 @@ more_balance: if (!cpumask_test_cpu(this_cpu, busiest->curr->cpus_ptr)) { raw_spin_unlock_irqrestore(&busiest->lock, flags); - env.flags |= LBF_ALL_PINNED; goto out_one_pinned; } + /* Record that we found at least one task that could run on this_cpu */ + env.flags &= ~LBF_ALL_PINNED; + /* * ->active_balance synchronizes accesses to * ->active_balance_work. Once set, it's cleared @@ -9781,21 +9780,13 @@ more_balance: /* We've kicked active balancing, force task migration. */ sd->nr_balance_failed = sd->cache_nice_tries+1; } - } else + } else { sd->nr_balance_failed = 0; + } - if (likely(!active_balance) || voluntary_active_balance(&env)) { + if (likely(!active_balance) || need_active_balance(&env)) { /* We were unbalanced, so reset the balancing interval */ sd->balance_interval = sd->min_interval; - } else { - /* - * If we've begun active balancing, start to back off. This - * case may not be covered by the all_pinned logic if there - * is only 1 task on the busy runqueue (because we don't call - * detach_tasks). - */ - if (sd->balance_interval < sd->max_interval) - sd->balance_interval *= 2; } goto out; @@ -10700,8 +10691,11 @@ static __latent_entropy void run_rebalance_domains(struct softirq_action *h) */ void trigger_load_balance(struct rq *rq) { - /* Don't need to rebalance while attached to NULL domain */ - if (unlikely(on_null_domain(rq))) + /* + * Don't need to rebalance while attached to NULL domain or + * runqueue CPU is not active + */ + if (unlikely(on_null_domain(rq) || !cpu_active(cpu_of(rq)))) return; if (time_after_eq(jiffies, rq->next_balance)) @@ -10806,7 +10800,7 @@ prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio) * our priority decreased, or if we are not currently running on * this runqueue and our priority is higher than the current's */ - if (rq->curr == p) { + if (task_current(rq, p)) { if (p->prio > oldprio) resched_curr(rq); } else @@ -10939,7 +10933,7 @@ static void switched_to_fair(struct rq *rq, struct task_struct *p) * kick off the schedule if running, otherwise just see * if we can still preempt the current task. */ - if (rq->curr == p) + if (task_current(rq, p)) resched_curr(rq); else check_preempt_curr(rq, p, 0); diff --git a/kernel/sched/features.h b/kernel/sched/features.h index 68d369cba9e4..1bc2b158fc51 100644 --- a/kernel/sched/features.h +++ b/kernel/sched/features.h @@ -38,6 +38,7 @@ SCHED_FEAT(CACHE_HOT_BUDDY, true) SCHED_FEAT(WAKEUP_PREEMPTION, true) SCHED_FEAT(HRTICK, false) +SCHED_FEAT(HRTICK_DL, false) SCHED_FEAT(DOUBLE_TICK, false) /* @@ -54,7 +55,6 @@ SCHED_FEAT(TTWU_QUEUE, true) /* * When doing wakeups, attempt to limit superfluous scans of the LLC domain. */ -SCHED_FEAT(SIS_AVG_CPU, false) SCHED_FEAT(SIS_PROP, true) /* diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index 305727ea0677..7199e6f23789 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -285,6 +285,7 @@ static void do_idle(void) } arch_cpu_idle_enter(); + rcu_nocb_flush_deferred_wakeup(); /* * In poll mode we reenable interrupts and spin. Also if we diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index dbe4629cf7ba..8f720b71d13d 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2357,7 +2357,7 @@ prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio) if (!task_on_rq_queued(p)) return; - if (rq->curr == p) { + if (task_current(rq, p)) { #ifdef CONFIG_SMP /* * If our priority decreases while running, we diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index bb09988451a0..10a1522b1e30 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -140,7 +140,7 @@ extern void call_trace_sched_update_nr_running(struct rq *rq, int count); * scale_load() and scale_load_down(w) to convert between them. The * following must be true: * - * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD + * scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD * */ #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT) @@ -1031,6 +1031,7 @@ struct rq { call_single_data_t hrtick_csd; #endif struct hrtimer hrtick_timer; + ktime_t hrtick_time; #endif #ifdef CONFIG_SCHEDSTATS @@ -2104,17 +2105,39 @@ extern const_debug unsigned int sysctl_sched_migration_cost; */ static inline int hrtick_enabled(struct rq *rq) { - if (!sched_feat(HRTICK)) - return 0; if (!cpu_active(cpu_of(rq))) return 0; return hrtimer_is_hres_active(&rq->hrtick_timer); } +static inline int hrtick_enabled_fair(struct rq *rq) +{ + if (!sched_feat(HRTICK)) + return 0; + return hrtick_enabled(rq); +} + +static inline int hrtick_enabled_dl(struct rq *rq) +{ + if (!sched_feat(HRTICK_DL)) + return 0; + return hrtick_enabled(rq); +} + void hrtick_start(struct rq *rq, u64 delay); #else +static inline int hrtick_enabled_fair(struct rq *rq) +{ + return 0; +} + +static inline int hrtick_enabled_dl(struct rq *rq) +{ + return 0; +} + static inline int hrtick_enabled(struct rq *rq) { return 0; @@ -2558,27 +2581,24 @@ static inline unsigned long capacity_orig_of(int cpu) { return cpu_rq(cpu)->cpu_capacity_orig; } -#endif /** - * enum schedutil_type - CPU utilization type + * enum cpu_util_type - CPU utilization type * @FREQUENCY_UTIL: Utilization used to select frequency * @ENERGY_UTIL: Utilization used during energy calculation * * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time * need to be aggregated differently depending on the usage made of them. This - * enum is used within schedutil_freq_util() to differentiate the types of + * enum is used within effective_cpu_util() to differentiate the types of * utilization expected by the callers, and adjust the aggregation accordingly. */ -enum schedutil_type { +enum cpu_util_type { FREQUENCY_UTIL, ENERGY_UTIL, }; -#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL - -unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs, - unsigned long max, enum schedutil_type type, +unsigned long effective_cpu_util(int cpu, unsigned long util_cfs, + unsigned long max, enum cpu_util_type type, struct task_struct *p); static inline unsigned long cpu_bw_dl(struct rq *rq) @@ -2607,14 +2627,7 @@ static inline unsigned long cpu_util_rt(struct rq *rq) { return READ_ONCE(rq->avg_rt.util_avg); } -#else /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */ -static inline unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs, - unsigned long max, enum schedutil_type type, - struct task_struct *p) -{ - return 0; -} -#endif /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */ +#endif #ifdef CONFIG_HAVE_SCHED_AVG_IRQ static inline unsigned long cpu_util_irq(struct rq *rq) diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 5d3675c7a76b..09d35044bd88 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -1596,66 +1596,58 @@ static void init_numa_topology_type(void) } } + +#define NR_DISTANCE_VALUES (1 << DISTANCE_BITS) + void sched_init_numa(void) { - int next_distance, curr_distance = node_distance(0, 0); struct sched_domain_topology_level *tl; - int level = 0; - int i, j, k; - - sched_domains_numa_distance = kzalloc(sizeof(int) * (nr_node_ids + 1), GFP_KERNEL); - if (!sched_domains_numa_distance) - return; - - /* Includes NUMA identity node at level 0. */ - sched_domains_numa_distance[level++] = curr_distance; - sched_domains_numa_levels = level; + unsigned long *distance_map; + int nr_levels = 0; + int i, j; /* * O(nr_nodes^2) deduplicating selection sort -- in order to find the * unique distances in the node_distance() table. - * - * Assumes node_distance(0,j) includes all distances in - * node_distance(i,j) in order to avoid cubic time. */ - next_distance = curr_distance; + distance_map = bitmap_alloc(NR_DISTANCE_VALUES, GFP_KERNEL); + if (!distance_map) + return; + + bitmap_zero(distance_map, NR_DISTANCE_VALUES); for (i = 0; i < nr_node_ids; i++) { for (j = 0; j < nr_node_ids; j++) { - for (k = 0; k < nr_node_ids; k++) { - int distance = node_distance(i, k); - - if (distance > curr_distance && - (distance < next_distance || - next_distance == curr_distance)) - next_distance = distance; - - /* - * While not a strong assumption it would be nice to know - * about cases where if node A is connected to B, B is not - * equally connected to A. - */ - if (sched_debug() && node_distance(k, i) != distance) - sched_numa_warn("Node-distance not symmetric"); + int distance = node_distance(i, j); - if (sched_debug() && i && !find_numa_distance(distance)) - sched_numa_warn("Node-0 not representative"); + if (distance < LOCAL_DISTANCE || distance >= NR_DISTANCE_VALUES) { + sched_numa_warn("Invalid distance value range"); + return; } - if (next_distance != curr_distance) { - sched_domains_numa_distance[level++] = next_distance; - sched_domains_numa_levels = level; - curr_distance = next_distance; - } else break; + + bitmap_set(distance_map, distance, 1); } + } + /* + * We can now figure out how many unique distance values there are and + * allocate memory accordingly. + */ + nr_levels = bitmap_weight(distance_map, NR_DISTANCE_VALUES); - /* - * In case of sched_debug() we verify the above assumption. - */ - if (!sched_debug()) - break; + sched_domains_numa_distance = kcalloc(nr_levels, sizeof(int), GFP_KERNEL); + if (!sched_domains_numa_distance) { + bitmap_free(distance_map); + return; + } + + for (i = 0, j = 0; i < nr_levels; i++, j++) { + j = find_next_bit(distance_map, NR_DISTANCE_VALUES, j); + sched_domains_numa_distance[i] = j; } + bitmap_free(distance_map); + /* - * 'level' contains the number of unique distances + * 'nr_levels' contains the number of unique distances * * The sched_domains_numa_distance[] array includes the actual distance * numbers. @@ -1664,15 +1656,15 @@ void sched_init_numa(void) /* * Here, we should temporarily reset sched_domains_numa_levels to 0. * If it fails to allocate memory for array sched_domains_numa_masks[][], - * the array will contain less then 'level' members. This could be + * the array will contain less then 'nr_levels' members. This could be * dangerous when we use it to iterate array sched_domains_numa_masks[][] * in other functions. * - * We reset it to 'level' at the end of this function. + * We reset it to 'nr_levels' at the end of this function. */ sched_domains_numa_levels = 0; - sched_domains_numa_masks = kzalloc(sizeof(void *) * level, GFP_KERNEL); + sched_domains_numa_masks = kzalloc(sizeof(void *) * nr_levels, GFP_KERNEL); if (!sched_domains_numa_masks) return; @@ -1680,7 +1672,7 @@ void sched_init_numa(void) * Now for each level, construct a mask per node which contains all * CPUs of nodes that are that many hops away from us. */ - for (i = 0; i < level; i++) { + for (i = 0; i < nr_levels; i++) { sched_domains_numa_masks[i] = kzalloc(nr_node_ids * sizeof(void *), GFP_KERNEL); if (!sched_domains_numa_masks[i]) @@ -1688,12 +1680,17 @@ void sched_init_numa(void) for (j = 0; j < nr_node_ids; j++) { struct cpumask *mask = kzalloc(cpumask_size(), GFP_KERNEL); + int k; + if (!mask) return; sched_domains_numa_masks[i][j] = mask; for_each_node(k) { + if (sched_debug() && (node_distance(j, k) != node_distance(k, j))) + sched_numa_warn("Node-distance not symmetric"); + if (node_distance(j, k) > sched_domains_numa_distance[i]) continue; @@ -1705,7 +1702,7 @@ void sched_init_numa(void) /* Compute default topology size */ for (i = 0; sched_domain_topology[i].mask; i++); - tl = kzalloc((i + level + 1) * + tl = kzalloc((i + nr_levels + 1) * sizeof(struct sched_domain_topology_level), GFP_KERNEL); if (!tl) return; @@ -1728,7 +1725,7 @@ void sched_init_numa(void) /* * .. and append 'j' levels of NUMA goodness. */ - for (j = 1; j < level; i++, j++) { + for (j = 1; j < nr_levels; i++, j++) { tl[i] = (struct sched_domain_topology_level){ .mask = sd_numa_mask, .sd_flags = cpu_numa_flags, @@ -1740,8 +1737,8 @@ void sched_init_numa(void) sched_domain_topology = tl; - sched_domains_numa_levels = level; - sched_max_numa_distance = sched_domains_numa_distance[level - 1]; + sched_domains_numa_levels = nr_levels; + sched_max_numa_distance = sched_domains_numa_distance[nr_levels - 1]; init_numa_topology_type(); } diff --git a/kernel/smp.c b/kernel/smp.c index 1b6070bf97bb..aeb0adfa0606 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -14,6 +14,7 @@ #include <linux/export.h> #include <linux/percpu.h> #include <linux/init.h> +#include <linux/interrupt.h> #include <linux/gfp.h> #include <linux/smp.h> #include <linux/cpu.h> @@ -449,6 +450,9 @@ void flush_smp_call_function_from_idle(void) local_irq_save(flags); flush_smp_call_function_queue(true); + if (local_softirq_pending()) + do_softirq(); + local_irq_restore(flags); } diff --git a/kernel/static_call.c b/kernel/static_call.c index 84565c2a41b8..6906c6ec4c97 100644 --- a/kernel/static_call.c +++ b/kernel/static_call.c @@ -12,6 +12,8 @@ extern struct static_call_site __start_static_call_sites[], __stop_static_call_sites[]; +extern struct static_call_tramp_key __start_static_call_tramp_key[], + __stop_static_call_tramp_key[]; static bool static_call_initialized; @@ -323,10 +325,59 @@ static int __static_call_mod_text_reserved(void *start, void *end) return ret; } +static unsigned long tramp_key_lookup(unsigned long addr) +{ + struct static_call_tramp_key *start = __start_static_call_tramp_key; + struct static_call_tramp_key *stop = __stop_static_call_tramp_key; + struct static_call_tramp_key *tramp_key; + + for (tramp_key = start; tramp_key != stop; tramp_key++) { + unsigned long tramp; + + tramp = (long)tramp_key->tramp + (long)&tramp_key->tramp; + if (tramp == addr) + return (long)tramp_key->key + (long)&tramp_key->key; + } + + return 0; +} + static int static_call_add_module(struct module *mod) { - return __static_call_init(mod, mod->static_call_sites, - mod->static_call_sites + mod->num_static_call_sites); + struct static_call_site *start = mod->static_call_sites; + struct static_call_site *stop = start + mod->num_static_call_sites; + struct static_call_site *site; + + for (site = start; site != stop; site++) { + unsigned long addr = (unsigned long)static_call_key(site); + unsigned long key; + + /* + * Is the key is exported, 'addr' points to the key, which + * means modules are allowed to call static_call_update() on + * it. + * + * Otherwise, the key isn't exported, and 'addr' points to the + * trampoline so we need to lookup the key. + * + * We go through this dance to prevent crazy modules from + * abusing sensitive static calls. + */ + if (!kernel_text_address(addr)) + continue; + + key = tramp_key_lookup(addr); + if (!key) { + pr_warn("Failed to fixup __raw_static_call() usage at: %ps\n", + static_call_addr(site)); + return -EINVAL; + } + + site->key = (key - (long)&site->key) | + (site->key & STATIC_CALL_SITE_FLAGS); + } + + return __static_call_init(mod, start, stop); } static void static_call_del_module(struct module *mod) @@ -438,6 +489,11 @@ int __init static_call_init(void) } early_initcall(static_call_init); +long __static_call_return0(void) +{ + return 0; +} + #ifdef CONFIG_STATIC_CALL_SELFTEST static int func_a(int x) diff --git a/lib/timerqueue.c b/lib/timerqueue.c index c52710964593..cdb9c7658478 100644 --- a/lib/timerqueue.c +++ b/lib/timerqueue.c @@ -14,6 +14,14 @@ #include <linux/rbtree.h> #include <linux/export.h> +#define __node_2_tq(_n) \ + rb_entry((_n), struct timerqueue_node, node) + +static inline bool __timerqueue_less(struct rb_node *a, const struct rb_node *b) +{ + return __node_2_tq(a)->expires < __node_2_tq(b)->expires; +} + /** * timerqueue_add - Adds timer to timerqueue. * @@ -26,28 +34,10 @@ */ bool timerqueue_add(struct timerqueue_head *head, struct timerqueue_node *node) { - struct rb_node **p = &head->rb_root.rb_root.rb_node; - struct rb_node *parent = NULL; - struct timerqueue_node *ptr; - bool leftmost = true; - /* Make sure we don't add nodes that are already added */ WARN_ON_ONCE(!RB_EMPTY_NODE(&node->node)); - while (*p) { - parent = *p; - ptr = rb_entry(parent, struct timerqueue_node, node); - if (node->expires < ptr->expires) { - p = &(*p)->rb_left; - } else { - p = &(*p)->rb_right; - leftmost = false; - } - } - rb_link_node(&node->node, parent, p); - rb_insert_color_cached(&node->node, &head->rb_root, leftmost); - - return leftmost; + return rb_add_cached(&node->node, &head->rb_root, __timerqueue_less); } EXPORT_SYMBOL_GPL(timerqueue_add); diff --git a/tools/include/linux/rbtree.h b/tools/include/linux/rbtree.h index 30dd21f976c3..2680f2edb837 100644 --- a/tools/include/linux/rbtree.h +++ b/tools/include/linux/rbtree.h @@ -152,4 +152,194 @@ static inline void rb_replace_node_cached(struct rb_node *victim, rb_replace_node(victim, new, &root->rb_root); } -#endif /* __TOOLS_LINUX_PERF_RBTREE_H */ +/* + * The below helper functions use 2 operators with 3 different + * calling conventions. The operators are related like: + * + * comp(a->key,b) < 0 := less(a,b) + * comp(a->key,b) > 0 := less(b,a) + * comp(a->key,b) == 0 := !less(a,b) && !less(b,a) + * + * If these operators define a partial order on the elements we make no + * guarantee on which of the elements matching the key is found. See + * rb_find(). + * + * The reason for this is to allow the find() interface without requiring an + * on-stack dummy object, which might not be feasible due to object size. + */ + +/** + * rb_add_cached() - insert @node into the leftmost cached tree @tree + * @node: node to insert + * @tree: leftmost cached tree to insert @node into + * @less: operator defining the (partial) node order + */ +static __always_inline void +rb_add_cached(struct rb_node *node, struct rb_root_cached *tree, + bool (*less)(struct rb_node *, const struct rb_node *)) +{ + struct rb_node **link = &tree->rb_root.rb_node; + struct rb_node *parent = NULL; + bool leftmost = true; + + while (*link) { + parent = *link; + if (less(node, parent)) { + link = &parent->rb_left; + } else { + link = &parent->rb_right; + leftmost = false; + } + } + + rb_link_node(node, parent, link); + rb_insert_color_cached(node, tree, leftmost); +} + +/** + * rb_add() - insert @node into @tree + * @node: node to insert + * @tree: tree to insert @node into + * @less: operator defining the (partial) node order + */ +static __always_inline void +rb_add(struct rb_node *node, struct rb_root *tree, + bool (*less)(struct rb_node *, const struct rb_node *)) +{ + struct rb_node **link = &tree->rb_node; + struct rb_node *parent = NULL; + + while (*link) { + parent = *link; + if (less(node, parent)) + link = &parent->rb_left; + else + link = &parent->rb_right; + } + + rb_link_node(node, parent, link); + rb_insert_color(node, tree); +} + +/** + * rb_find_add() - find equivalent @node in @tree, or add @node + * @node: node to look-for / insert + * @tree: tree to search / modify + * @cmp: operator defining the node order + * + * Returns the rb_node matching @node, or NULL when no match is found and @node + * is inserted. + */ +static __always_inline struct rb_node * +rb_find_add(struct rb_node *node, struct rb_root *tree, + int (*cmp)(struct rb_node *, const struct rb_node *)) +{ + struct rb_node **link = &tree->rb_node; + struct rb_node *parent = NULL; + int c; + + while (*link) { + parent = *link; + c = cmp(node, parent); + + if (c < 0) + link = &parent->rb_left; + else if (c > 0) + link = &parent->rb_right; + else + return parent; + } + + rb_link_node(node, parent, link); + rb_insert_color(node, tree); + return NULL; +} + +/** + * rb_find() - find @key in tree @tree + * @key: key to match + * @tree: tree to search + * @cmp: operator defining the node order + * + * Returns the rb_node matching @key or NULL. + */ +static __always_inline struct rb_node * +rb_find(const void *key, const struct rb_root *tree, + int (*cmp)(const void *key, const struct rb_node *)) +{ + struct rb_node *node = tree->rb_node; + + while (node) { + int c = cmp(key, node); + + if (c < 0) + node = node->rb_left; + else if (c > 0) + node = node->rb_right; + else + return node; + } + + return NULL; +} + +/** + * rb_find_first() - find the first @key in @tree + * @key: key to match + * @tree: tree to search + * @cmp: operator defining node order + * + * Returns the leftmost node matching @key, or NULL. + */ +static __always_inline struct rb_node * +rb_find_first(const void *key, const struct rb_root *tree, + int (*cmp)(const void *key, const struct rb_node *)) +{ + struct rb_node *node = tree->rb_node; + struct rb_node *match = NULL; + + while (node) { + int c = cmp(key, node); + + if (c <= 0) { + if (!c) + match = node; + node = node->rb_left; + } else if (c > 0) { + node = node->rb_right; + } + } + + return match; +} + +/** + * rb_next_match() - find the next @key in @tree + * @key: key to match + * @tree: tree to search + * @cmp: operator defining node order + * + * Returns the next node matching @key, or NULL. + */ +static __always_inline struct rb_node * +rb_next_match(const void *key, struct rb_node *node, + int (*cmp)(const void *key, const struct rb_node *)) +{ + node = rb_next(node); + if (node && cmp(key, node)) + node = NULL; + return node; +} + +/** + * rb_for_each() - iterates a subtree matching @key + * @node: iterator + * @key: key to match + * @tree: tree to search + * @cmp: operator defining node order + */ +#define rb_for_each(node, key, tree, cmp) \ + for ((node) = rb_find_first((key), (tree), (cmp)); \ + (node); (node) = rb_next_match((key), (node), (cmp))) + +#endif /* __TOOLS_LINUX_PERF_RBTREE_H */ diff --git a/tools/include/linux/static_call_types.h b/tools/include/linux/static_call_types.h index 89135bb35bf7..ae5662d368b9 100644 --- a/tools/include/linux/static_call_types.h +++ b/tools/include/linux/static_call_types.h @@ -4,11 +4,13 @@ #include <linux/types.h> #include <linux/stringify.h> +#include <linux/compiler.h> #define STATIC_CALL_KEY_PREFIX __SCK__ #define STATIC_CALL_KEY_PREFIX_STR __stringify(STATIC_CALL_KEY_PREFIX) #define STATIC_CALL_KEY_PREFIX_LEN (sizeof(STATIC_CALL_KEY_PREFIX_STR) - 1) #define STATIC_CALL_KEY(name) __PASTE(STATIC_CALL_KEY_PREFIX, name) +#define STATIC_CALL_KEY_STR(name) __stringify(STATIC_CALL_KEY(name)) #define STATIC_CALL_TRAMP_PREFIX __SCT__ #define STATIC_CALL_TRAMP_PREFIX_STR __stringify(STATIC_CALL_TRAMP_PREFIX) @@ -32,4 +34,52 @@ struct static_call_site { s32 key; }; +#define DECLARE_STATIC_CALL(name, func) \ + extern struct static_call_key STATIC_CALL_KEY(name); \ + extern typeof(func) STATIC_CALL_TRAMP(name); + +#ifdef CONFIG_HAVE_STATIC_CALL + +#define __raw_static_call(name) (&STATIC_CALL_TRAMP(name)) + +#ifdef CONFIG_HAVE_STATIC_CALL_INLINE + +/* + * __ADDRESSABLE() is used to ensure the key symbol doesn't get stripped from + * the symbol table so that objtool can reference it when it generates the + * .static_call_sites section. + */ +#define __STATIC_CALL_ADDRESSABLE(name) \ + __ADDRESSABLE(STATIC_CALL_KEY(name)) + +#define __static_call(name) \ +({ \ + __STATIC_CALL_ADDRESSABLE(name); \ + __raw_static_call(name); \ +}) + +#else /* !CONFIG_HAVE_STATIC_CALL_INLINE */ + +#define __STATIC_CALL_ADDRESSABLE(name) +#define __static_call(name) __raw_static_call(name) + +#endif /* CONFIG_HAVE_STATIC_CALL_INLINE */ + +#ifdef MODULE +#define __STATIC_CALL_MOD_ADDRESSABLE(name) +#define static_call_mod(name) __raw_static_call(name) +#else +#define __STATIC_CALL_MOD_ADDRESSABLE(name) __STATIC_CALL_ADDRESSABLE(name) +#define static_call_mod(name) __static_call(name) +#endif + +#define static_call(name) __static_call(name) + +#else + +#define static_call(name) \ + ((typeof(STATIC_CALL_TRAMP(name))*)(STATIC_CALL_KEY(name).func)) + +#endif /* CONFIG_HAVE_STATIC_CALL */ + #endif /* _STATIC_CALL_TYPES_H */ diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 4bd30315eb62..f2e5e5ce1a05 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -502,8 +502,21 @@ static int create_static_call_sections(struct objtool_file *file) key_sym = find_symbol_by_name(file->elf, tmp); if (!key_sym) { - WARN("static_call: can't find static_call_key symbol: %s", tmp); - return -1; + if (!module) { + WARN("static_call: can't find static_call_key symbol: %s", tmp); + return -1; + } + + /* + * For modules(), the key might not be exported, which + * means the module can make static calls but isn't + * allowed to change them. + * + * In that case we temporarily set the key to be the + * trampoline address. This is fixed up in + * static_call_add_module(). + */ + key_sym = insn->call_dest; } free(key_name); diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index d8421e1d06be..e85988ce04f1 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -43,75 +43,24 @@ static void elf_hash_init(struct hlist_head *table) #define elf_hash_for_each_possible(name, obj, member, key) \ hlist_for_each_entry(obj, &name[hash_min(key, elf_hash_bits())], member) -static void rb_add(struct rb_root *tree, struct rb_node *node, - int (*cmp)(struct rb_node *, const struct rb_node *)) -{ - struct rb_node **link = &tree->rb_node; - struct rb_node *parent = NULL; - - while (*link) { - parent = *link; - if (cmp(node, parent) < 0) - link = &parent->rb_left; - else - link = &parent->rb_right; - } - - rb_link_node(node, parent, link); - rb_insert_color(node, tree); -} - -static struct rb_node *rb_find_first(const struct rb_root *tree, const void *key, - int (*cmp)(const void *key, const struct rb_node *)) -{ - struct rb_node *node = tree->rb_node; - struct rb_node *match = NULL; - - while (node) { - int c = cmp(key, node); - if (c <= 0) { - if (!c) - match = node; - node = node->rb_left; - } else if (c > 0) { - node = node->rb_right; - } - } - - return match; -} - -static struct rb_node *rb_next_match(struct rb_node *node, const void *key, - int (*cmp)(const void *key, const struct rb_node *)) -{ - node = rb_next(node); - if (node && cmp(key, node)) - node = NULL; - return node; -} - -#define rb_for_each(tree, node, key, cmp) \ - for ((node) = rb_find_first((tree), (key), (cmp)); \ - (node); (node) = rb_next_match((node), (key), (cmp))) - -static int symbol_to_offset(struct rb_node *a, const struct rb_node *b) +static bool symbol_to_offset(struct rb_node *a, const struct rb_node *b) { struct symbol *sa = rb_entry(a, struct symbol, node); struct symbol *sb = rb_entry(b, struct symbol, node); if (sa->offset < sb->offset) - return -1; + return true; if (sa->offset > sb->offset) - return 1; + return false; if (sa->len < sb->len) - return -1; + return true; if (sa->len > sb->len) - return 1; + return false; sa->alias = sb; - return 0; + return false; } static int symbol_by_offset(const void *key, const struct rb_node *node) @@ -165,7 +114,7 @@ struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset) { struct rb_node *node; - rb_for_each(&sec->symbol_tree, node, &offset, symbol_by_offset) { + rb_for_each(node, &offset, &sec->symbol_tree, symbol_by_offset) { struct symbol *s = rb_entry(node, struct symbol, node); if (s->offset == offset && s->type != STT_SECTION) @@ -179,7 +128,7 @@ struct symbol *find_func_by_offset(struct section *sec, unsigned long offset) { struct rb_node *node; - rb_for_each(&sec->symbol_tree, node, &offset, symbol_by_offset) { + rb_for_each(node, &offset, &sec->symbol_tree, symbol_by_offset) { struct symbol *s = rb_entry(node, struct symbol, node); if (s->offset == offset && s->type == STT_FUNC) @@ -193,7 +142,7 @@ struct symbol *find_symbol_containing(const struct section *sec, unsigned long o { struct rb_node *node; - rb_for_each(&sec->symbol_tree, node, &offset, symbol_by_offset) { + rb_for_each(node, &offset, &sec->symbol_tree, symbol_by_offset) { struct symbol *s = rb_entry(node, struct symbol, node); if (s->type != STT_SECTION) @@ -207,7 +156,7 @@ struct symbol *find_func_containing(struct section *sec, unsigned long offset) { struct rb_node *node; - rb_for_each(&sec->symbol_tree, node, &offset, symbol_by_offset) { + rb_for_each(node, &offset, &sec->symbol_tree, symbol_by_offset) { struct symbol *s = rb_entry(node, struct symbol, node); if (s->type == STT_FUNC) @@ -442,7 +391,7 @@ static int read_symbols(struct elf *elf) sym->offset = sym->sym.st_value; sym->len = sym->sym.st_size; - rb_add(&sym->sec->symbol_tree, &sym->node, symbol_to_offset); + rb_add(&sym->node, &sym->sec->symbol_tree, symbol_to_offset); pnode = rb_prev(&sym->node); if (pnode) entry = &rb_entry(pnode, struct symbol, node)->list; |