diff options
Diffstat (limited to 'arch/riscv/kernel')
| -rw-r--r-- | arch/riscv/kernel/Makefile | 4 | ||||
| -rw-r--r-- | arch/riscv/kernel/entry.S | 6 | ||||
| -rw-r--r-- | arch/riscv/kernel/fpu.S | 8 | ||||
| -rw-r--r-- | arch/riscv/kernel/head.S | 2 | ||||
| -rw-r--r-- | arch/riscv/kernel/perf_callchain.c | 94 | ||||
| -rw-r--r-- | arch/riscv/kernel/perf_regs.c | 44 | ||||
| -rw-r--r-- | arch/riscv/kernel/smp.c | 60 | ||||
| -rw-r--r-- | arch/riscv/kernel/stacktrace.c | 4 |
8 files changed, 187 insertions, 35 deletions
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 2420d37d96de..696020ff72db 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -38,6 +38,8 @@ obj-$(CONFIG_MODULE_SECTIONS) += module-sections.o obj-$(CONFIG_FUNCTION_TRACER) += mcount.o ftrace.o obj-$(CONFIG_DYNAMIC_FTRACE) += mcount-dyn.o -obj-$(CONFIG_PERF_EVENTS) += perf_event.o +obj-$(CONFIG_PERF_EVENTS) += perf_event.o +obj-$(CONFIG_PERF_EVENTS) += perf_callchain.o +obj-$(CONFIG_HAVE_PERF_REGS) += perf_regs.o clean: diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index bc7a56e1ca6f..74ccfd464071 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -167,7 +167,7 @@ ENTRY(handle_exception) tail do_IRQ 1: /* Exceptions run with interrupts enabled */ - csrs sstatus, SR_SIE + csrs CSR_SSTATUS, SR_SIE /* Handle syscalls */ li t0, EXC_SYSCALL @@ -222,7 +222,7 @@ ret_from_syscall: ret_from_exception: REG_L s0, PT_SSTATUS(sp) - csrc sstatus, SR_SIE + csrc CSR_SSTATUS, SR_SIE andi s0, s0, SR_SPP bnez s0, resume_kernel @@ -265,7 +265,7 @@ work_pending: bnez s1, work_resched work_notifysig: /* Handle pending signals and notify-resume requests */ - csrs sstatus, SR_SIE /* Enable interrupts for do_notify_resume() */ + csrs CSR_SSTATUS, SR_SIE /* Enable interrupts for do_notify_resume() */ move a0, sp /* pt_regs */ move a1, s0 /* current_thread_info->flags */ tail do_notify_resume diff --git a/arch/riscv/kernel/fpu.S b/arch/riscv/kernel/fpu.S index 1defb0618aff..631d31540660 100644 --- a/arch/riscv/kernel/fpu.S +++ b/arch/riscv/kernel/fpu.S @@ -23,7 +23,7 @@ ENTRY(__fstate_save) li a2, TASK_THREAD_F0 add a0, a0, a2 li t1, SR_FS - csrs sstatus, t1 + csrs CSR_SSTATUS, t1 frcsr t0 fsd f0, TASK_THREAD_F0_F0(a0) fsd f1, TASK_THREAD_F1_F0(a0) @@ -58,7 +58,7 @@ ENTRY(__fstate_save) fsd f30, TASK_THREAD_F30_F0(a0) fsd f31, TASK_THREAD_F31_F0(a0) sw t0, TASK_THREAD_FCSR_F0(a0) - csrc sstatus, t1 + csrc CSR_SSTATUS, t1 ret ENDPROC(__fstate_save) @@ -67,7 +67,7 @@ ENTRY(__fstate_restore) add a0, a0, a2 li t1, SR_FS lw t0, TASK_THREAD_FCSR_F0(a0) - csrs sstatus, t1 + csrs CSR_SSTATUS, t1 fld f0, TASK_THREAD_F0_F0(a0) fld f1, TASK_THREAD_F1_F0(a0) fld f2, TASK_THREAD_F2_F0(a0) @@ -101,6 +101,6 @@ ENTRY(__fstate_restore) fld f30, TASK_THREAD_F30_F0(a0) fld f31, TASK_THREAD_F31_F0(a0) fscsr t0 - csrc sstatus, t1 + csrc CSR_SSTATUS, t1 ret ENDPROC(__fstate_restore) diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index 52eec0c1bf30..15a9189f91ad 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -61,7 +61,7 @@ _start_kernel: * floating point in kernel space */ li t0, SR_FS - csrc sstatus, t0 + csrc CSR_SSTATUS, t0 /* Pick one hart to run the main boot sequence */ la a3, hart_lottery diff --git a/arch/riscv/kernel/perf_callchain.c b/arch/riscv/kernel/perf_callchain.c new file mode 100644 index 000000000000..8d2804f05cf9 --- /dev/null +++ b/arch/riscv/kernel/perf_callchain.c @@ -0,0 +1,94 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd. */ + +#include <linux/perf_event.h> +#include <linux/uaccess.h> + +/* Kernel callchain */ +struct stackframe { + unsigned long fp; + unsigned long ra; +}; + +/* + * Get the return address for a single stackframe and return a pointer to the + * next frame tail. + */ +static unsigned long user_backtrace(struct perf_callchain_entry_ctx *entry, + unsigned long fp, unsigned long reg_ra) +{ + struct stackframe buftail; + unsigned long ra = 0; + unsigned long *user_frame_tail = + (unsigned long *)(fp - sizeof(struct stackframe)); + + /* Check accessibility of one struct frame_tail beyond */ + if (!access_ok(user_frame_tail, sizeof(buftail))) + return 0; + if (__copy_from_user_inatomic(&buftail, user_frame_tail, + sizeof(buftail))) + return 0; + + if (reg_ra != 0) + ra = reg_ra; + else + ra = buftail.ra; + + fp = buftail.fp; + if (ra != 0) + perf_callchain_store(entry, ra); + else + return 0; + + return fp; +} + +/* + * This will be called when the target is in user mode + * This function will only be called when we use + * "PERF_SAMPLE_CALLCHAIN" in + * kernel/events/core.c:perf_prepare_sample() + * + * How to trigger perf_callchain_[user/kernel] : + * $ perf record -e cpu-clock --call-graph fp ./program + * $ perf report --call-graph + * + * On RISC-V platform, the program being sampled and the C library + * need to be compiled with -fno-omit-frame-pointer, otherwise + * the user stack will not contain function frame. + */ +void perf_callchain_user(struct perf_callchain_entry_ctx *entry, + struct pt_regs *regs) +{ + unsigned long fp = 0; + + /* RISC-V does not support perf in guest mode. */ + if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) + return; + + fp = regs->s0; + perf_callchain_store(entry, regs->sepc); + + fp = user_backtrace(entry, fp, regs->ra); + while (fp && !(fp & 0x3) && entry->nr < entry->max_stack) + fp = user_backtrace(entry, fp, 0); +} + +bool fill_callchain(unsigned long pc, void *entry) +{ + return perf_callchain_store(entry, pc); +} + +void notrace walk_stackframe(struct task_struct *task, + struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg); +void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, + struct pt_regs *regs) +{ + /* RISC-V does not support perf in guest mode. */ + if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) { + pr_warn("RISC-V does not support perf in guest mode!"); + return; + } + + walk_stackframe(NULL, regs, fill_callchain, entry); +} diff --git a/arch/riscv/kernel/perf_regs.c b/arch/riscv/kernel/perf_regs.c new file mode 100644 index 000000000000..04a38fbeb9c7 --- /dev/null +++ b/arch/riscv/kernel/perf_regs.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd. */ + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/perf_event.h> +#include <linux/bug.h> +#include <asm/perf_regs.h> +#include <asm/ptrace.h> + +u64 perf_reg_value(struct pt_regs *regs, int idx) +{ + if (WARN_ON_ONCE((u32)idx >= PERF_REG_RISCV_MAX)) + return 0; + + return ((unsigned long *)regs)[idx]; +} + +#define REG_RESERVED (~((1ULL << PERF_REG_RISCV_MAX) - 1)) + +int perf_reg_validate(u64 mask) +{ + if (!mask || mask & REG_RESERVED) + return -EINVAL; + + return 0; +} + +u64 perf_reg_abi(struct task_struct *task) +{ +#if __riscv_xlen == 64 + return PERF_SAMPLE_REGS_ABI_64; +#else + return PERF_SAMPLE_REGS_ABI_32; +#endif +} + +void perf_get_regs_user(struct perf_regs *regs_user, + struct pt_regs *regs, + struct pt_regs *regs_user_copy) +{ + regs_user->regs = task_pt_regs(current); + regs_user->abi = perf_reg_abi(current); +} diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c index 5a9834503a2f..3836760d7aaf 100644 --- a/arch/riscv/kernel/smp.c +++ b/arch/riscv/kernel/smp.c @@ -56,6 +56,7 @@ void riscv_cpuid_to_hartid_mask(const struct cpumask *in, struct cpumask *out) { int cpu; + cpumask_clear(out); for_each_cpu(cpu, in) cpumask_set_cpu(cpuid_to_hartid_map(cpu), out); } @@ -78,13 +79,42 @@ static void ipi_stop(void) wait_for_interrupt(); } +static void send_ipi_mask(const struct cpumask *mask, enum ipi_message_type op) +{ + struct cpumask hartid_mask; + int cpu; + + smp_mb__before_atomic(); + for_each_cpu(cpu, mask) + set_bit(op, &ipi_data[cpu].bits); + smp_mb__after_atomic(); + + riscv_cpuid_to_hartid_mask(mask, &hartid_mask); + sbi_send_ipi(cpumask_bits(&hartid_mask)); +} + +static void send_ipi_single(int cpu, enum ipi_message_type op) +{ + int hartid = cpuid_to_hartid_map(cpu); + + smp_mb__before_atomic(); + set_bit(op, &ipi_data[cpu].bits); + smp_mb__after_atomic(); + + sbi_send_ipi(cpumask_bits(cpumask_of(hartid))); +} + +static inline void clear_ipi(void) +{ + csr_clear(CSR_SIP, SIE_SSIE); +} + void riscv_software_interrupt(void) { unsigned long *pending_ipis = &ipi_data[smp_processor_id()].bits; unsigned long *stats = ipi_data[smp_processor_id()].stats; - /* Clear pending IPI */ - csr_clear(CSR_SIP, SIE_SSIE); + clear_ipi(); while (true) { unsigned long ops; @@ -118,23 +148,6 @@ void riscv_software_interrupt(void) } } -static void -send_ipi_message(const struct cpumask *to_whom, enum ipi_message_type operation) -{ - int cpuid, hartid; - struct cpumask hartid_mask; - - cpumask_clear(&hartid_mask); - mb(); - for_each_cpu(cpuid, to_whom) { - set_bit(operation, &ipi_data[cpuid].bits); - hartid = cpuid_to_hartid_map(cpuid); - cpumask_set_cpu(hartid, &hartid_mask); - } - mb(); - sbi_send_ipi(cpumask_bits(&hartid_mask)); -} - static const char * const ipi_names[] = { [IPI_RESCHEDULE] = "Rescheduling interrupts", [IPI_CALL_FUNC] = "Function call interrupts", @@ -156,12 +169,12 @@ void show_ipi_stats(struct seq_file *p, int prec) void arch_send_call_function_ipi_mask(struct cpumask *mask) { - send_ipi_message(mask, IPI_CALL_FUNC); + send_ipi_mask(mask, IPI_CALL_FUNC); } void arch_send_call_function_single_ipi(int cpu) { - send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC); + send_ipi_single(cpu, IPI_CALL_FUNC); } void smp_send_stop(void) @@ -176,7 +189,7 @@ void smp_send_stop(void) if (system_state <= SYSTEM_RUNNING) pr_crit("SMP: stopping secondary CPUs\n"); - send_ipi_message(&mask, IPI_CPU_STOP); + send_ipi_mask(&mask, IPI_CPU_STOP); } /* Wait up to one second for other CPUs to stop */ @@ -191,6 +204,5 @@ void smp_send_stop(void) void smp_send_reschedule(int cpu) { - send_ipi_message(cpumask_of(cpu), IPI_RESCHEDULE); + send_ipi_single(cpu, IPI_RESCHEDULE); } - diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c index f15642715d1a..0940681d2f68 100644 --- a/arch/riscv/kernel/stacktrace.c +++ b/arch/riscv/kernel/stacktrace.c @@ -19,8 +19,8 @@ struct stackframe { unsigned long ra; }; -static void notrace walk_stackframe(struct task_struct *task, - struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg) +void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs, + bool (*fn)(unsigned long, void *), void *arg) { unsigned long fp, sp, pc; |