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-rw-r--r--kernel/trace/Kconfig30
-rw-r--r--kernel/trace/Makefile3
-rw-r--r--kernel/trace/ftrace.c267
-rw-r--r--kernel/trace/trace.c441
-rw-r--r--kernel/trace/trace.h46
-rw-r--r--kernel/trace/trace_benchmark.c198
-rw-r--r--kernel/trace/trace_benchmark.h41
-rw-r--r--kernel/trace/trace_events.c13
-rw-r--r--kernel/trace/trace_functions.c56
-rw-r--r--kernel/trace/trace_functions_graph.c19
-rw-r--r--kernel/trace/trace_irqsoff.c71
-rw-r--r--kernel/trace/trace_kprobe.c3
-rw-r--r--kernel/trace/trace_nop.c1
-rw-r--r--kernel/trace/trace_output.c41
-rw-r--r--kernel/trace/trace_sched_wakeup.c70
-rw-r--r--kernel/trace/trace_selftest.c69
-rw-r--r--kernel/trace/trace_stack.c42
17 files changed, 951 insertions, 460 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 8639819f6cef..d4409356f40d 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -535,6 +535,36 @@ config MMIOTRACE_TEST
Say N, unless you absolutely know what you are doing.
+config TRACEPOINT_BENCHMARK
+ bool "Add tracepoint that benchmarks tracepoints"
+ help
+ This option creates the tracepoint "benchmark:benchmark_event".
+ When the tracepoint is enabled, it kicks off a kernel thread that
+ goes into an infinite loop (calling cond_sched() to let other tasks
+ run), and calls the tracepoint. Each iteration will record the time
+ it took to write to the tracepoint and the next iteration that
+ data will be passed to the tracepoint itself. That is, the tracepoint
+ will report the time it took to do the previous tracepoint.
+ The string written to the tracepoint is a static string of 128 bytes
+ to keep the time the same. The initial string is simply a write of
+ "START". The second string records the cold cache time of the first
+ write which is not added to the rest of the calculations.
+
+ As it is a tight loop, it benchmarks as hot cache. That's fine because
+ we care most about hot paths that are probably in cache already.
+
+ An example of the output:
+
+ START
+ first=3672 [COLD CACHED]
+ last=632 first=3672 max=632 min=632 avg=316 std=446 std^2=199712
+ last=278 first=3672 max=632 min=278 avg=303 std=316 std^2=100337
+ last=277 first=3672 max=632 min=277 avg=296 std=258 std^2=67064
+ last=273 first=3672 max=632 min=273 avg=292 std=224 std^2=50411
+ last=273 first=3672 max=632 min=273 avg=288 std=200 std^2=40389
+ last=281 first=3672 max=632 min=273 avg=287 std=183 std^2=33666
+
+
config RING_BUFFER_BENCHMARK
tristate "Ring buffer benchmark stress tester"
depends on RING_BUFFER
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 1378e84fbe39..2611613f14f1 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -17,6 +17,7 @@ ifdef CONFIG_TRACING_BRANCHES
KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
endif
+CFLAGS_trace_benchmark.o := -I$(src)
CFLAGS_trace_events_filter.o := -I$(src)
obj-$(CONFIG_TRACE_CLOCK) += trace_clock.o
@@ -62,4 +63,6 @@ endif
obj-$(CONFIG_PROBE_EVENTS) += trace_probe.o
obj-$(CONFIG_UPROBE_EVENT) += trace_uprobe.o
+obj-$(CONFIG_TRACEPOINT_BENCHMARK) += trace_benchmark.o
+
libftrace-y := ftrace.o
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 4a54a25afa2f..5b372e3ed675 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -62,7 +62,7 @@
#define FTRACE_HASH_DEFAULT_BITS 10
#define FTRACE_HASH_MAX_BITS 12
-#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_CONTROL)
+#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_CONTROL)
#ifdef CONFIG_DYNAMIC_FTRACE
#define INIT_REGEX_LOCK(opsname) \
@@ -103,7 +103,6 @@ static int ftrace_disabled __read_mostly;
static DEFINE_MUTEX(ftrace_lock);
-static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end;
static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end;
static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end;
ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
@@ -171,23 +170,6 @@ int ftrace_nr_registered_ops(void)
return cnt;
}
-static void
-ftrace_global_list_func(unsigned long ip, unsigned long parent_ip,
- struct ftrace_ops *op, struct pt_regs *regs)
-{
- int bit;
-
- bit = trace_test_and_set_recursion(TRACE_GLOBAL_START, TRACE_GLOBAL_MAX);
- if (bit < 0)
- return;
-
- do_for_each_ftrace_op(op, ftrace_global_list) {
- op->func(ip, parent_ip, op, regs);
- } while_for_each_ftrace_op(op);
-
- trace_clear_recursion(bit);
-}
-
static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs)
{
@@ -237,43 +219,6 @@ static int control_ops_alloc(struct ftrace_ops *ops)
return 0;
}
-static void update_global_ops(void)
-{
- ftrace_func_t func = ftrace_global_list_func;
- void *private = NULL;
-
- /* The list has its own recursion protection. */
- global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
-
- /*
- * If there's only one function registered, then call that
- * function directly. Otherwise, we need to iterate over the
- * registered callers.
- */
- if (ftrace_global_list == &ftrace_list_end ||
- ftrace_global_list->next == &ftrace_list_end) {
- func = ftrace_global_list->func;
- private = ftrace_global_list->private;
- /*
- * As we are calling the function directly.
- * If it does not have recursion protection,
- * the function_trace_op needs to be updated
- * accordingly.
- */
- if (!(ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE))
- global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE;
- }
-
- /* If we filter on pids, update to use the pid function */
- if (!list_empty(&ftrace_pids)) {
- set_ftrace_pid_function(func);
- func = ftrace_pid_func;
- }
-
- global_ops.func = func;
- global_ops.private = private;
-}
-
static void ftrace_sync(struct work_struct *work)
{
/*
@@ -301,8 +246,6 @@ static void update_ftrace_function(void)
{
ftrace_func_t func;
- update_global_ops();
-
/*
* If we are at the end of the list and this ops is
* recursion safe and not dynamic and the arch supports passing ops,
@@ -314,10 +257,7 @@ static void update_ftrace_function(void)
(ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) &&
!FTRACE_FORCE_LIST_FUNC)) {
/* Set the ftrace_ops that the arch callback uses */
- if (ftrace_ops_list == &global_ops)
- set_function_trace_op = ftrace_global_list;
- else
- set_function_trace_op = ftrace_ops_list;
+ set_function_trace_op = ftrace_ops_list;
func = ftrace_ops_list->func;
} else {
/* Just use the default ftrace_ops */
@@ -373,6 +313,11 @@ static void update_ftrace_function(void)
ftrace_trace_function = func;
}
+int using_ftrace_ops_list_func(void)
+{
+ return ftrace_trace_function == ftrace_ops_list_func;
+}
+
static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops)
{
ops->next = *list;
@@ -434,16 +379,9 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
if (ops->flags & FTRACE_OPS_FL_DELETED)
return -EINVAL;
- if (FTRACE_WARN_ON(ops == &global_ops))
- return -EINVAL;
-
if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED))
return -EBUSY;
- /* We don't support both control and global flags set. */
- if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK)
- return -EINVAL;
-
#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS
/*
* If the ftrace_ops specifies SAVE_REGS, then it only can be used
@@ -461,10 +399,7 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
if (!core_kernel_data((unsigned long)ops))
ops->flags |= FTRACE_OPS_FL_DYNAMIC;
- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- add_ftrace_list_ops(&ftrace_global_list, &global_ops, ops);
- ops->flags |= FTRACE_OPS_FL_ENABLED;
- } else if (ops->flags & FTRACE_OPS_FL_CONTROL) {
+ if (ops->flags & FTRACE_OPS_FL_CONTROL) {
if (control_ops_alloc(ops))
return -ENOMEM;
add_ftrace_list_ops(&ftrace_control_list, &control_ops, ops);
@@ -484,15 +419,7 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED)))
return -EBUSY;
- if (FTRACE_WARN_ON(ops == &global_ops))
- return -EINVAL;
-
- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- ret = remove_ftrace_list_ops(&ftrace_global_list,
- &global_ops, ops);
- if (!ret)
- ops->flags &= ~FTRACE_OPS_FL_ENABLED;
- } else if (ops->flags & FTRACE_OPS_FL_CONTROL) {
+ if (ops->flags & FTRACE_OPS_FL_CONTROL) {
ret = remove_ftrace_list_ops(&ftrace_control_list,
&control_ops, ops);
} else
@@ -895,7 +822,7 @@ function_profile_call(unsigned long ip, unsigned long parent_ip,
local_irq_save(flags);
- stat = &__get_cpu_var(ftrace_profile_stats);
+ stat = this_cpu_ptr(&ftrace_profile_stats);
if (!stat->hash || !ftrace_profile_enabled)
goto out;
@@ -926,7 +853,7 @@ static void profile_graph_return(struct ftrace_graph_ret *trace)
unsigned long flags;
local_irq_save(flags);
- stat = &__get_cpu_var(ftrace_profile_stats);
+ stat = this_cpu_ptr(&ftrace_profile_stats);
if (!stat->hash || !ftrace_profile_enabled)
goto out;
@@ -1178,7 +1105,7 @@ struct ftrace_page {
static struct ftrace_page *ftrace_pages_start;
static struct ftrace_page *ftrace_pages;
-static bool ftrace_hash_empty(struct ftrace_hash *hash)
+static bool __always_inline ftrace_hash_empty(struct ftrace_hash *hash)
{
return !hash || !hash->count;
}
@@ -1625,7 +1552,14 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip);
/*
+ * If filter_hash is set, we want to match all functions
+ * that are in the hash but not in the other hash.
*
+ * If filter_hash is not set, then we are decrementing.
+ * That means we match anything that is in the hash
+ * and also in the other_hash. That is, we need to turn
+ * off functions in the other hash because they are disabled
+ * by this hash.
*/
if (filter_hash && in_hash && !in_other_hash)
match = 1;
@@ -1767,19 +1701,15 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update)
/*
* If this record is being updated from a nop, then
* return UPDATE_MAKE_CALL.
- * Otherwise, if the EN flag is set, then return
- * UPDATE_MODIFY_CALL_REGS to tell the caller to convert
- * from the non-save regs, to a save regs function.
* Otherwise,
* return UPDATE_MODIFY_CALL to tell the caller to convert
- * from the save regs, to a non-save regs function.
+ * from the save regs, to a non-save regs function or
+ * vice versa.
*/
if (flag & FTRACE_FL_ENABLED)
return FTRACE_UPDATE_MAKE_CALL;
- else if (rec->flags & FTRACE_FL_REGS_EN)
- return FTRACE_UPDATE_MODIFY_CALL_REGS;
- else
- return FTRACE_UPDATE_MODIFY_CALL;
+
+ return FTRACE_UPDATE_MODIFY_CALL;
}
if (update) {
@@ -1821,6 +1751,42 @@ int ftrace_test_record(struct dyn_ftrace *rec, int enable)
return ftrace_check_record(rec, enable, 0);
}
+/**
+ * ftrace_get_addr_new - Get the call address to set to
+ * @rec: The ftrace record descriptor
+ *
+ * If the record has the FTRACE_FL_REGS set, that means that it
+ * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS
+ * is not not set, then it wants to convert to the normal callback.
+ *
+ * Returns the address of the trampoline to set to
+ */
+unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec)
+{
+ if (rec->flags & FTRACE_FL_REGS)
+ return (unsigned long)FTRACE_REGS_ADDR;
+ else
+ return (unsigned long)FTRACE_ADDR;
+}
+
+/**
+ * ftrace_get_addr_curr - Get the call address that is already there
+ * @rec: The ftrace record descriptor
+ *
+ * The FTRACE_FL_REGS_EN is set when the record already points to
+ * a function that saves all the regs. Basically the '_EN' version
+ * represents the current state of the function.
+ *
+ * Returns the address of the trampoline that is currently being called
+ */
+unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec)
+{
+ if (rec->flags & FTRACE_FL_REGS_EN)
+ return (unsigned long)FTRACE_REGS_ADDR;
+ else
+ return (unsigned long)FTRACE_ADDR;
+}
+
static int
__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
{
@@ -1828,12 +1794,12 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
unsigned long ftrace_addr;
int ret;
- ret = ftrace_update_record(rec, enable);
+ ftrace_addr = ftrace_get_addr_new(rec);
- if (rec->flags & FTRACE_FL_REGS)
- ftrace_addr = (unsigned long)FTRACE_REGS_ADDR;
- else
- ftrace_addr = (unsigned long)FTRACE_ADDR;
+ /* This needs to be done before we call ftrace_update_record */
+ ftrace_old_addr = ftrace_get_addr_curr(rec);
+
+ ret = ftrace_update_record(rec, enable);
switch (ret) {
case FTRACE_UPDATE_IGNORE:
@@ -1845,13 +1811,7 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
case FTRACE_UPDATE_MAKE_NOP:
return ftrace_make_nop(NULL, rec, ftrace_addr);
- case FTRACE_UPDATE_MODIFY_CALL_REGS:
case FTRACE_UPDATE_MODIFY_CALL:
- if (rec->flags & FTRACE_FL_REGS)
- ftrace_old_addr = (unsigned long)FTRACE_ADDR;
- else
- ftrace_old_addr = (unsigned long)FTRACE_REGS_ADDR;
-
return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr);
}
@@ -2115,7 +2075,6 @@ static void ftrace_startup_enable(int command)
static int ftrace_startup(struct ftrace_ops *ops, int command)
{
- bool hash_enable = true;
int ret;
if (unlikely(ftrace_disabled))
@@ -2128,18 +2087,9 @@ static int ftrace_startup(struct ftrace_ops *ops, int command)
ftrace_start_up++;
command |= FTRACE_UPDATE_CALLS;
- /* ops marked global share the filter hashes */
- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- ops = &global_ops;
- /* Don't update hash if global is already set */
- if (global_start_up)
- hash_enable = false;
- global_start_up++;
- }
-
ops->flags |= FTRACE_OPS_FL_ENABLED;
- if (hash_enable)
- ftrace_hash_rec_enable(ops, 1);
+
+ ftrace_hash_rec_enable(ops, 1);
ftrace_startup_enable(command);
@@ -2148,7 +2098,6 @@ static int ftrace_startup(struct ftrace_ops *ops, int command)
static int ftrace_shutdown(struct ftrace_ops *ops, int command)
{
- bool hash_disable = true;
int ret;
if (unlikely(ftrace_disabled))
@@ -2166,21 +2115,9 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command)
*/
WARN_ON_ONCE(ftrace_start_up < 0);
- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- ops = &global_ops;
- global_start_up--;
- WARN_ON_ONCE(global_start_up < 0);
- /* Don't update hash if global still has users */
- if (global_start_up) {
- WARN_ON_ONCE(!ftrace_start_up);
- hash_disable = false;
- }
- }
-
- if (hash_disable)
- ftrace_hash_rec_disable(ops, 1);
+ ftrace_hash_rec_disable(ops, 1);
- if (ops != &global_ops || !global_start_up)
+ if (!global_start_up)
ops->flags &= ~FTRACE_OPS_FL_ENABLED;
command |= FTRACE_UPDATE_CALLS;
@@ -3524,10 +3461,6 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
struct ftrace_hash *hash;
int ret;
- /* All global ops uses the global ops filters */
- if (ops->flags & FTRACE_OPS_FL_GLOBAL)
- ops = &global_ops;
-
if (unlikely(ftrace_disabled))
return -ENODEV;
@@ -3639,8 +3572,7 @@ int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
}
EXPORT_SYMBOL_GPL(ftrace_set_notrace);
/**
- * ftrace_set_filter - set a function to filter on in ftrace
- * @ops - the ops to set the filter with
+ * ftrace_set_global_filter - set a function to filter on with global tracers
* @buf - the string that holds the function filter text.
* @len - the length of the string.
* @reset - non zero to reset all filters before applying this filter.
@@ -3655,8 +3587,7 @@ void ftrace_set_global_filter(unsigned char *buf, int len, int reset)
EXPORT_SYMBOL_GPL(ftrace_set_global_filter);
/**
- * ftrace_set_notrace - set a function to not trace in ftrace
- * @ops - the ops to set the notrace filter with
+ * ftrace_set_global_notrace - set a function to not trace with global tracers
* @buf - the string that holds the function notrace text.
* @len - the length of the string.
* @reset - non zero to reset all filters before applying this filter.
@@ -4443,6 +4374,34 @@ ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs)
#endif /* CONFIG_DYNAMIC_FTRACE */
+__init void ftrace_init_global_array_ops(struct trace_array *tr)
+{
+ tr->ops = &global_ops;
+ tr->ops->private = tr;
+}
+
+void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func)
+{
+ /* If we filter on pids, update to use the pid function */
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL) {
+ if (WARN_ON(tr->ops->func != ftrace_stub))
+ printk("ftrace ops had %pS for function\n",
+ tr->ops->func);
+ /* Only the top level instance does pid tracing */
+ if (!list_empty(&ftrace_pids)) {
+ set_ftrace_pid_function(func);
+ func = ftrace_pid_func;
+ }
+ }
+ tr->ops->func = func;
+ tr->ops->private = tr;
+}
+
+void ftrace_reset_array_ops(struct trace_array *tr)
+{
+ tr->ops->func = ftrace_stub;
+}
+
static void
ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs)
@@ -4501,9 +4460,16 @@ __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
*/
preempt_disable_notrace();
do_for_each_ftrace_op(op, ftrace_ops_list) {
- if (ftrace_ops_test(op, ip, regs))
+ if (ftrace_ops_test(op, ip, regs)) {
+ if (WARN_ON(!op->func)) {
+ function_trace_stop = 1;
+ printk("op=%p %pS\n", op, op);
+ goto out;
+ }
op->func(ip, parent_ip, op, regs);
+ }
} while_for_each_ftrace_op(op);
+out:
preempt_enable_notrace();
trace_clear_recursion(bit);
}
@@ -4908,7 +4874,6 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static int ftrace_graph_active;
-static struct notifier_block ftrace_suspend_notifier;
int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace)
{
@@ -5054,13 +5019,6 @@ ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state,
return NOTIFY_DONE;
}
-/* Just a place holder for function graph */
-static struct ftrace_ops fgraph_ops __read_mostly = {
- .func = ftrace_stub,
- .flags = FTRACE_OPS_FL_STUB | FTRACE_OPS_FL_GLOBAL |
- FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace)
{
if (!ftrace_ops_test(&global_ops, trace->func, NULL))
@@ -5085,6 +5043,10 @@ static void update_function_graph_func(void)
ftrace_graph_entry = ftrace_graph_entry_test;
}
+static struct notifier_block ftrace_suspend_notifier = {
+ .notifier_call = ftrace_suspend_notifier_call,
+};
+
int register_ftrace_graph(trace_func_graph_ret_t retfunc,
trace_func_graph_ent_t entryfunc)
{
@@ -5098,7 +5060,6 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
goto out;
}
- ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call;
register_pm_notifier(&ftrace_suspend_notifier);
ftrace_graph_active++;
@@ -5120,7 +5081,10 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
ftrace_graph_entry = ftrace_graph_entry_test;
update_function_graph_func();
- ret = ftrace_startup(&fgraph_ops, FTRACE_START_FUNC_RET);
+ /* Function graph doesn't use the .func field of global_ops */
+ global_ops.flags |= FTRACE_OPS_FL_STUB;
+
+ ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET);
out:
mutex_unlock(&ftrace_lock);
@@ -5138,7 +5102,8 @@ void unregister_ftrace_graph(void)
ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
ftrace_graph_entry = ftrace_graph_entry_stub;
__ftrace_graph_entry = ftrace_graph_entry_stub;
- ftrace_shutdown(&fgraph_ops, FTRACE_STOP_FUNC_RET);
+ ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET);
+ global_ops.flags &= ~FTRACE_OPS_FL_STUB;
unregister_pm_notifier(&ftrace_suspend_notifier);
unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 737b0efa1a62..16f7038d1f4d 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -275,7 +275,7 @@ int call_filter_check_discard(struct ftrace_event_call *call, void *rec,
}
EXPORT_SYMBOL_GPL(call_filter_check_discard);
-cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu)
+static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu)
{
u64 ts;
@@ -599,7 +599,7 @@ static int alloc_snapshot(struct trace_array *tr)
return 0;
}
-void free_snapshot(struct trace_array *tr)
+static void free_snapshot(struct trace_array *tr)
{
/*
* We don't free the ring buffer. instead, resize it because
@@ -963,27 +963,9 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
return cnt;
}
-/*
- * ftrace_max_lock is used to protect the swapping of buffers
- * when taking a max snapshot. The buffers themselves are
- * protected by per_cpu spinlocks. But the action of the swap
- * needs its own lock.
- *
- * This is defined as a arch_spinlock_t in order to help
- * with performance when lockdep debugging is enabled.
- *
- * It is also used in other places outside the update_max_tr
- * so it needs to be defined outside of the
- * CONFIG_TRACER_MAX_TRACE.
- */
-static arch_spinlock_t ftrace_max_lock =
- (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
-
unsigned long __read_mostly tracing_thresh;
#ifdef CONFIG_TRACER_MAX_TRACE
-unsigned long __read_mostly tracing_max_latency;
-
/*
* Copy the new maximum trace into the separate maximum-trace
* structure. (this way the maximum trace is permanently saved,
@@ -1000,7 +982,7 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
max_buf->cpu = cpu;
max_buf->time_start = data->preempt_timestamp;
- max_data->saved_latency = tracing_max_latency;
+ max_data->saved_latency = tr->max_latency;
max_data->critical_start = data->critical_start;
max_data->critical_end = data->critical_end;
@@ -1048,14 +1030,14 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
return;
}
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&tr->max_lock);
buf = tr->trace_buffer.buffer;
tr->trace_buffer.buffer = tr->max_buffer.buffer;
tr->max_buffer.buffer = buf;
__update_max_tr(tr, tsk, cpu);
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&tr->max_lock);
}
/**
@@ -1081,7 +1063,7 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
return;
}
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&tr->max_lock);
ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu);
@@ -1099,11 +1081,11 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY);
__update_max_tr(tr, tsk, cpu);
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&tr->max_lock);
}
#endif /* CONFIG_TRACER_MAX_TRACE */
-static void default_wait_pipe(struct trace_iterator *iter)
+static void wait_on_pipe(struct trace_iterator *iter)
{
/* Iterators are static, they should be filled or empty */
if (trace_buffer_iter(iter, iter->cpu_file))
@@ -1220,8 +1202,6 @@ int register_tracer(struct tracer *type)
else
if (!type->flags->opts)
type->flags->opts = dummy_tracer_opt;
- if (!type->wait_pipe)
- type->wait_pipe = default_wait_pipe;
ret = run_tracer_selftest(type);
if (ret < 0)
@@ -1305,22 +1285,71 @@ void tracing_reset_all_online_cpus(void)
}
}
-#define SAVED_CMDLINES 128
+#define SAVED_CMDLINES_DEFAULT 128
#define NO_CMDLINE_MAP UINT_MAX
-static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1];
-static unsigned map_cmdline_to_pid[SAVED_CMDLINES];
-static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN];
-static int cmdline_idx;
static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED;
+struct saved_cmdlines_buffer {
+ unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1];
+ unsigned *map_cmdline_to_pid;
+ unsigned cmdline_num;
+ int cmdline_idx;
+ char *saved_cmdlines;
+};
+static struct saved_cmdlines_buffer *savedcmd;
/* temporary disable recording */
static atomic_t trace_record_cmdline_disabled __read_mostly;
-static void trace_init_cmdlines(void)
+static inline char *get_saved_cmdlines(int idx)
{
- memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline));
- memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid));
- cmdline_idx = 0;
+ return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN];
+}
+
+static inline void set_cmdline(int idx, const char *cmdline)
+{
+ memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN);
+}
+
+static int allocate_cmdlines_buffer(unsigned int val,
+ struct saved_cmdlines_buffer *s)
+{
+ s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid),
+ GFP_KERNEL);
+ if (!s->map_cmdline_to_pid)
+ return -ENOMEM;
+
+ s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL);
+ if (!s->saved_cmdlines) {
+ kfree(s->map_cmdline_to_pid);
+ return -ENOMEM;
+ }
+
+ s->cmdline_idx = 0;
+ s->cmdline_num = val;
+ memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP,
+ sizeof(s->map_pid_to_cmdline));
+ memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP,
+ val * sizeof(*s->map_cmdline_to_pid));
+
+ return 0;
+}
+
+static int trace_create_savedcmd(void)
+{
+ int ret;
+
+ savedcmd = kmalloc(sizeof(struct saved_cmdlines_buffer), GFP_KERNEL);
+ if (!savedcmd)
+ return -ENOMEM;
+
+ ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd);
+ if (ret < 0) {
+ kfree(savedcmd);
+ savedcmd = NULL;
+ return -ENOMEM;
+ }
+
+ return 0;
}
int is_tracing_stopped(void)
@@ -1353,7 +1382,7 @@ void tracing_start(void)
}
/* Prevent the buffers from switching */
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&global_trace.max_lock);
buffer = global_trace.trace_buffer.buffer;
if (buffer)
@@ -1365,7 +1394,7 @@ void tracing_start(void)
ring_buffer_record_enable(buffer);
#endif
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&global_trace.max_lock);
ftrace_start();
out:
@@ -1420,7 +1449,7 @@ void tracing_stop(void)
goto out;
/* Prevent the buffers from switching */
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&global_trace.max_lock);
buffer = global_trace.trace_buffer.buffer;
if (buffer)
@@ -1432,7 +1461,7 @@ void tracing_stop(void)
ring_buffer_record_disable(buffer);
#endif
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&global_trace.max_lock);
out:
raw_spin_unlock_irqrestore(&global_trace.start_lock, flags);
@@ -1461,12 +1490,12 @@ static void tracing_stop_tr(struct trace_array *tr)
void trace_stop_cmdline_recording(void);
-static void trace_save_cmdline(struct task_struct *tsk)
+static int trace_save_cmdline(struct task_struct *tsk)
{
unsigned pid, idx;
if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT))
- return;
+ return 0;
/*
* It's not the end of the world if we don't get
@@ -1475,11 +1504,11 @@ static void trace_save_cmdline(struct task_struct *tsk)
* so if we miss here, then better luck next time.
*/
if (!arch_spin_trylock(&trace_cmdline_lock))
- return;
+ return 0;
- idx = map_pid_to_cmdline[tsk->pid];
+ idx = savedcmd->map_pid_to_cmdline[tsk->pid];
if (idx == NO_CMDLINE_MAP) {
- idx = (cmdline_idx + 1) % SAVED_CMDLINES;
+ idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num;
/*
* Check whether the cmdline buffer at idx has a pid
@@ -1487,22 +1516,24 @@ static void trace_save_cmdline(struct task_struct *tsk)
* need to clear the map_pid_to_cmdline. Otherwise we
* would read the new comm for the old pid.
*/
- pid = map_cmdline_to_pid[idx];
+ pid = savedcmd->map_cmdline_to_pid[idx];
if (pid != NO_CMDLINE_MAP)
- map_pid_to_cmdline[pid] = NO_CMDLINE_MAP;
+ savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP;
- map_cmdline_to_pid[idx] = tsk->pid;
- map_pid_to_cmdline[tsk->pid] = idx;
+ savedcmd->map_cmdline_to_pid[idx] = tsk->pid;
+ savedcmd->map_pid_to_cmdline[tsk->pid] = idx;
- cmdline_idx = idx;
+ savedcmd->cmdline_idx = idx;
}
- memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN);
+ set_cmdline(idx, tsk->comm);
arch_spin_unlock(&trace_cmdline_lock);
+
+ return 1;
}
-void trace_find_cmdline(int pid, char comm[])
+static void __trace_find_cmdline(int pid, char comm[])
{
unsigned map;
@@ -1521,13 +1552,19 @@ void trace_find_cmdline(int pid, char comm[])
return;
}
- preempt_disable();
- arch_spin_lock(&trace_cmdline_lock);
- map = map_pid_to_cmdline[pid];
+ map = savedcmd->map_pid_to_cmdline[pid];
if (map != NO_CMDLINE_MAP)
- strcpy(comm, saved_cmdlines[map]);
+ strcpy(comm, get_saved_cmdlines(map));
else
strcpy(comm, "<...>");
+}
+
+void trace_find_cmdline(int pid, char comm[])
+{
+ preempt_disable();
+ arch_spin_lock(&trace_cmdline_lock);
+
+ __trace_find_cmdline(pid, comm);
arch_spin_unlock(&trace_cmdline_lock);
preempt_enable();
@@ -1541,9 +1578,8 @@ void tracing_record_cmdline(struct task_struct *tsk)
if (!__this_cpu_read(trace_cmdline_save))
return;
- __this_cpu_write(trace_cmdline_save, false);
-
- trace_save_cmdline(tsk);
+ if (trace_save_cmdline(tsk))
+ __this_cpu_write(trace_cmdline_save, false);
}
void
@@ -1746,7 +1782,7 @@ static void __ftrace_trace_stack(struct ring_buffer *buffer,
*/
barrier();
if (use_stack == 1) {
- trace.entries = &__get_cpu_var(ftrace_stack).calls[0];
+ trace.entries = this_cpu_ptr(ftrace_stack.calls);
trace.max_entries = FTRACE_STACK_MAX_ENTRIES;
if (regs)
@@ -1995,7 +2031,21 @@ void trace_printk_init_buffers(void)
if (alloc_percpu_trace_buffer())
return;
- pr_info("ftrace: Allocated trace_printk buffers\n");
+ /* trace_printk() is for debug use only. Don't use it in production. */
+
+ pr_warning("\n**********************************************************\n");
+ pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
+ pr_warning("** **\n");
+ pr_warning("** trace_printk() being used. Allocating extra memory. **\n");
+ pr_warning("** **\n");
+ pr_warning("** This means that this is a DEBUG kernel and it is **\n");
+ pr_warning("** unsafe for produciton use. **\n");
+ pr_warning("** **\n");
+ pr_warning("** If you see this message and you are not debugging **\n");
+ pr_warning("** the kernel, report this immediately to your vendor! **\n");
+ pr_warning("** **\n");
+ pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
+ pr_warning("**********************************************************\n");
/* Expand the buffers to set size */
tracing_update_buffers();
@@ -3333,7 +3383,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
mutex_lock(&tracing_cpumask_update_lock);
local_irq_disable();
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&tr->max_lock);
for_each_tracing_cpu(cpu) {
/*
* Increase/decrease the disabled counter if we are
@@ -3350,7 +3400,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu);
}
}
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&tr->max_lock);
local_irq_enable();
cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new);
@@ -3592,6 +3642,7 @@ static const char readme_msg[] =
" trace_options\t\t- Set format or modify how tracing happens\n"
"\t\t\t Disable an option by adding a suffix 'no' to the\n"
"\t\t\t option name\n"
+ " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n"
#ifdef CONFIG_DYNAMIC_FTRACE
"\n available_filter_functions - list of functions that can be filtered on\n"
" set_ftrace_filter\t- echo function name in here to only trace these\n"
@@ -3705,55 +3756,153 @@ static const struct file_operations tracing_readme_fops = {
.llseek = generic_file_llseek,
};
+static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ unsigned int *ptr = v;
+
+ if (*pos || m->count)
+ ptr++;
+
+ (*pos)++;
+
+ for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num];
+ ptr++) {
+ if (*ptr == -1 || *ptr == NO_CMDLINE_MAP)
+ continue;
+
+ return ptr;
+ }
+
+ return NULL;
+}
+
+static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos)
+{
+ void *v;
+ loff_t l = 0;
+
+ preempt_disable();
+ arch_spin_lock(&trace_cmdline_lock);
+
+ v = &savedcmd->map_cmdline_to_pid[0];
+ while (l <= *pos) {
+ v = saved_cmdlines_next(m, v, &l);
+ if (!v)
+ return NULL;
+ }
+
+ return v;
+}
+
+static void saved_cmdlines_stop(struct seq_file *m, void *v)
+{
+ arch_spin_unlock(&trace_cmdline_lock);
+ preempt_enable();
+}
+
+static int saved_cmdlines_show(struct seq_file *m, void *v)
+{
+ char buf[TASK_COMM_LEN];
+ unsigned int *pid = v;
+
+ __trace_find_cmdline(*pid, buf);
+ seq_printf(m, "%d %s\n", *pid, buf);
+ return 0;
+}
+
+static const struct seq_operations tracing_saved_cmdlines_seq_ops = {
+ .start = saved_cmdlines_start,
+ .next = saved_cmdlines_next,
+ .stop = saved_cmdlines_stop,
+ .show = saved_cmdlines_show,
+};
+
+static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp)
+{
+ if (tracing_disabled)
+ return -ENODEV;
+
+ return seq_open(filp, &tracing_saved_cmdlines_seq_ops);
+}
+
+static const struct file_operations tracing_saved_cmdlines_fops = {
+ .open = tracing_saved_cmdlines_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
static ssize_t
-tracing_saved_cmdlines_read(struct file *file, char __user *ubuf,
- size_t cnt, loff_t *ppos)
+tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
{
- char *buf_comm;
- char *file_buf;
- char *buf;
- int len = 0;
- int pid;
- int i;
+ char buf[64];
+ int r;
+
+ arch_spin_lock(&trace_cmdline_lock);
+ r = sprintf(buf, "%u\n", savedcmd->cmdline_num);
+ arch_spin_unlock(&trace_cmdline_lock);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s)
+{
+ kfree(s->saved_cmdlines);
+ kfree(s->map_cmdline_to_pid);
+ kfree(s);
+}
+
+static int tracing_resize_saved_cmdlines(unsigned int val)
+{
+ struct saved_cmdlines_buffer *s, *savedcmd_temp;
- file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL);
- if (!file_buf)
+ s = kmalloc(sizeof(struct saved_cmdlines_buffer), GFP_KERNEL);
+ if (!s)
return -ENOMEM;
- buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL);
- if (!buf_comm) {
- kfree(file_buf);
+ if (allocate_cmdlines_buffer(val, s) < 0) {
+ kfree(s);
return -ENOMEM;
}
- buf = file_buf;
+ arch_spin_lock(&trace_cmdline_lock);
+ savedcmd_temp = savedcmd;
+ savedcmd = s;
+ arch_spin_unlock(&trace_cmdline_lock);
+ free_saved_cmdlines_buffer(savedcmd_temp);
- for (i = 0; i < SAVED_CMDLINES; i++) {
- int r;
+ return 0;
+}
- pid = map_cmdline_to_pid[i];
- if (pid == -1 || pid == NO_CMDLINE_MAP)
- continue;
+static ssize_t
+tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ unsigned long val;
+ int ret;
- trace_find_cmdline(pid, buf_comm);
- r = sprintf(buf, "%d %s\n", pid, buf_comm);
- buf += r;
- len += r;
- }
+ ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+ if (ret)
+ return ret;
- len = simple_read_from_buffer(ubuf, cnt, ppos,
- file_buf, len);
+ /* must have at least 1 entry or less than PID_MAX_DEFAULT */
+ if (!val || val > PID_MAX_DEFAULT)
+ return -EINVAL;
- kfree(file_buf);
- kfree(buf_comm);
+ ret = tracing_resize_saved_cmdlines((unsigned int)val);
+ if (ret < 0)
+ return ret;
- return len;
+ *ppos += cnt;
+
+ return cnt;
}
-static const struct file_operations tracing_saved_cmdlines_fops = {
- .open = tracing_open_generic,
- .read = tracing_saved_cmdlines_read,
- .llseek = generic_file_llseek,
+static const struct file_operations tracing_saved_cmdlines_size_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_saved_cmdlines_size_read,
+ .write = tracing_saved_cmdlines_size_write,
};
static ssize_t
@@ -4225,25 +4374,6 @@ tracing_poll_pipe(struct file *filp, poll_table *poll_table)
return trace_poll(iter, filp, poll_table);
}
-/*
- * This is a make-shift waitqueue.
- * A tracer might use this callback on some rare cases:
- *
- * 1) the current tracer might hold the runqueue lock when it wakes up
- * a reader, hence a deadlock (sched, function, and function graph tracers)
- * 2) the function tracers, trace all functions, we don't want
- * the overhead of calling wake_up and friends
- * (and tracing them too)
- *
- * Anyway, this is really very primitive wakeup.
- */
-void poll_wait_pipe(struct trace_iterator *iter)
-{
- set_current_state(TASK_INTERRUPTIBLE);
- /* sleep for 100 msecs, and try again. */
- schedule_timeout(HZ / 10);
-}
-
/* Must be called with trace_types_lock mutex held. */
static int tracing_wait_pipe(struct file *filp)
{
@@ -4255,15 +4385,6 @@ static int tracing_wait_pipe(struct file *filp)
return -EAGAIN;
}
- mutex_unlock(&iter->mutex);
-
- iter->trace->wait_pipe(iter);
-
- mutex_lock(&iter->mutex);
-
- if (signal_pending(current))
- return -EINTR;
-
/*
* We block until we read something and tracing is disabled.
* We still block if tracing is disabled, but we have never
@@ -4275,6 +4396,15 @@ static int tracing_wait_pipe(struct file *filp)
*/
if (!tracing_is_on() && iter->pos)
break;
+
+ mutex_unlock(&iter->mutex);
+
+ wait_on_pipe(iter);
+
+ mutex_lock(&iter->mutex);
+
+ if (signal_pending(current))
+ return -EINTR;
}
return 1;
@@ -5197,7 +5327,7 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
goto out_unlock;
}
mutex_unlock(&trace_types_lock);
- iter->trace->wait_pipe(iter);
+ wait_on_pipe(iter);
mutex_lock(&trace_types_lock);
if (signal_pending(current)) {
size = -EINTR;
@@ -5408,7 +5538,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
goto out;
}
mutex_unlock(&trace_types_lock);
- iter->trace->wait_pipe(iter);
+ wait_on_pipe(iter);
mutex_lock(&trace_types_lock);
if (signal_pending(current)) {
ret = -EINTR;
@@ -6102,6 +6232,25 @@ static int allocate_trace_buffers(struct trace_array *tr, int size)
return 0;
}
+static void free_trace_buffers(struct trace_array *tr)
+{
+ if (!tr)
+ return;
+
+ if (tr->trace_buffer.buffer) {
+ ring_buffer_free(tr->trace_buffer.buffer);
+ tr->trace_buffer.buffer = NULL;
+ free_percpu(tr->trace_buffer.data);
+ }
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ if (tr->max_buffer.buffer) {
+ ring_buffer_free(tr->max_buffer.buffer);
+ tr->max_buffer.buffer = NULL;
+ }
+#endif
+}
+
static int new_instance_create(const char *name)
{
struct trace_array *tr;
@@ -6131,6 +6280,8 @@ static int new_instance_create(const char *name)
raw_spin_lock_init(&tr->start_lock);
+ tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
+
tr->current_trace = &nop_trace;
INIT_LIST_HEAD(&tr->systems);
@@ -6158,8 +6309,7 @@ static int new_instance_create(const char *name)
return 0;
out_free_tr:
- if (tr->trace_buffer.buffer)
- ring_buffer_free(tr->trace_buffer.buffer);
+ free_trace_buffers(tr);
free_cpumask_var(tr->tracing_cpumask);
kfree(tr->name);
kfree(tr);
@@ -6199,8 +6349,7 @@ static int instance_delete(const char *name)
event_trace_del_tracer(tr);
ftrace_destroy_function_files(tr);
debugfs_remove_recursive(tr->dir);
- free_percpu(tr->trace_buffer.data);
- ring_buffer_free(tr->trace_buffer.buffer);
+ free_trace_buffers(tr);
kfree(tr->name);
kfree(tr);
@@ -6328,6 +6477,11 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
trace_create_file("tracing_on", 0644, d_tracer,
tr, &rb_simple_fops);
+#ifdef CONFIG_TRACER_MAX_TRACE
+ trace_create_file("tracing_max_latency", 0644, d_tracer,
+ &tr->max_latency, &tracing_max_lat_fops);
+#endif
+
if (ftrace_create_function_files(tr, d_tracer))
WARN(1, "Could not allocate function filter files");
@@ -6353,11 +6507,6 @@ static __init int tracer_init_debugfs(void)
init_tracer_debugfs(&global_trace, d_tracer);
-#ifdef CONFIG_TRACER_MAX_TRACE
- trace_create_file("tracing_max_latency", 0644, d_tracer,
- &tracing_max_latency, &tracing_max_lat_fops);
-#endif
-
trace_create_file("tracing_thresh", 0644, d_tracer,
&tracing_thresh, &tracing_max_lat_fops);
@@ -6367,6 +6516,9 @@ static __init int tracer_init_debugfs(void)
trace_create_file("saved_cmdlines", 0444, d_tracer,
NULL, &tracing_saved_cmdlines_fops);
+ trace_create_file("saved_cmdlines_size", 0644, d_tracer,
+ NULL, &tracing_saved_cmdlines_size_fops);
+
#ifdef CONFIG_DYNAMIC_FTRACE
trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,
&ftrace_update_tot_cnt, &tracing_dyn_info_fops);
@@ -6603,18 +6755,19 @@ __init static int tracer_alloc_buffers(void)
if (!temp_buffer)
goto out_free_cpumask;
+ if (trace_create_savedcmd() < 0)
+ goto out_free_temp_buffer;
+
/* TODO: make the number of buffers hot pluggable with CPUS */
if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) {
printk(KERN_ERR "tracer: failed to allocate ring buffer!\n");
WARN_ON(1);
- goto out_free_temp_buffer;
+ goto out_free_savedcmd;
}
if (global_trace.buffer_disabled)
tracing_off();
- trace_init_cmdlines();
-
if (trace_boot_clock) {
ret = tracing_set_clock(&global_trace, trace_boot_clock);
if (ret < 0)
@@ -6629,6 +6782,10 @@ __init static int tracer_alloc_buffers(void)
*/
global_trace.current_trace = &nop_trace;
+ global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
+
+ ftrace_init_global_array_ops(&global_trace);
+
register_tracer(&nop_trace);
/* All seems OK, enable tracing */
@@ -6656,13 +6813,11 @@ __init static int tracer_alloc_buffers(void)
return 0;
+out_free_savedcmd:
+ free_saved_cmdlines_buffer(savedcmd);
out_free_temp_buffer:
ring_buffer_free(temp_buffer);
out_free_cpumask:
- free_percpu(global_trace.trace_buffer.data);
-#ifdef CONFIG_TRACER_MAX_TRACE
- free_percpu(global_trace.max_buffer.data);
-#endif
free_cpumask_var(global_trace.tracing_cpumask);
out_free_buffer_mask:
free_cpumask_var(tracing_buffer_mask);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 2e29d7ba5a52..9e82551dd566 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -190,7 +190,22 @@ struct trace_array {
*/
struct trace_buffer max_buffer;
bool allocated_snapshot;
+ unsigned long max_latency;
#endif
+ /*
+ * max_lock is used to protect the swapping of buffers
+ * when taking a max snapshot. The buffers themselves are
+ * protected by per_cpu spinlocks. But the action of the swap
+ * needs its own lock.
+ *
+ * This is defined as a arch_spinlock_t in order to help
+ * with performance when lockdep debugging is enabled.
+ *
+ * It is also used in other places outside the update_max_tr
+ * so it needs to be defined outside of the
+ * CONFIG_TRACER_MAX_TRACE.
+ */
+ arch_spinlock_t max_lock;
int buffer_disabled;
#ifdef CONFIG_FTRACE_SYSCALLS
int sys_refcount_enter;
@@ -237,6 +252,9 @@ static inline struct trace_array *top_trace_array(void)
{
struct trace_array *tr;
+ if (list_empty(ftrace_trace_arrays.prev))
+ return NULL;
+
tr = list_entry(ftrace_trace_arrays.prev,
typeof(*tr), list);
WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
@@ -323,7 +341,6 @@ struct tracer_flags {
* @stop: called when tracing is paused (echo 0 > tracing_enabled)
* @open: called when the trace file is opened
* @pipe_open: called when the trace_pipe file is opened
- * @wait_pipe: override how the user waits for traces on trace_pipe
* @close: called when the trace file is released
* @pipe_close: called when the trace_pipe file is released
* @read: override the default read callback on trace_pipe
@@ -342,7 +359,6 @@ struct tracer {
void (*stop)(struct trace_array *tr);
void (*open)(struct trace_iterator *iter);
void (*pipe_open)(struct trace_iterator *iter);
- void (*wait_pipe)(struct trace_iterator *iter);
void (*close)(struct trace_iterator *iter);
void (*pipe_close)(struct trace_iterator *iter);
ssize_t (*read)(struct trace_iterator *iter,
@@ -416,13 +432,7 @@ enum {
TRACE_FTRACE_IRQ_BIT,
TRACE_FTRACE_SIRQ_BIT,
- /* GLOBAL_BITs must be greater than FTRACE_BITs */
- TRACE_GLOBAL_BIT,
- TRACE_GLOBAL_NMI_BIT,
- TRACE_GLOBAL_IRQ_BIT,
- TRACE_GLOBAL_SIRQ_BIT,
-
- /* INTERNAL_BITs must be greater than GLOBAL_BITs */
+ /* INTERNAL_BITs must be greater than FTRACE_BITs */
TRACE_INTERNAL_BIT,
TRACE_INTERNAL_NMI_BIT,
TRACE_INTERNAL_IRQ_BIT,
@@ -449,9 +459,6 @@ enum {
#define TRACE_FTRACE_START TRACE_FTRACE_BIT
#define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
-#define TRACE_GLOBAL_START TRACE_GLOBAL_BIT
-#define TRACE_GLOBAL_MAX ((1 << (TRACE_GLOBAL_START + TRACE_CONTEXT_BITS)) - 1)
-
#define TRACE_LIST_START TRACE_INTERNAL_BIT
#define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
@@ -560,8 +567,6 @@ void trace_init_global_iter(struct trace_iterator *iter);
void tracing_iter_reset(struct trace_iterator *iter, int cpu);
-void poll_wait_pipe(struct trace_iterator *iter);
-
void tracing_sched_switch_trace(struct trace_array *tr,
struct task_struct *prev,
struct task_struct *next,
@@ -608,8 +613,6 @@ extern unsigned long nsecs_to_usecs(unsigned long nsecs);
extern unsigned long tracing_thresh;
#ifdef CONFIG_TRACER_MAX_TRACE
-extern unsigned long tracing_max_latency;
-
void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
void update_max_tr_single(struct trace_array *tr,
struct task_struct *tsk, int cpu);
@@ -724,6 +727,8 @@ extern unsigned long trace_flags;
#define TRACE_GRAPH_PRINT_PROC 0x8
#define TRACE_GRAPH_PRINT_DURATION 0x10
#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
+#define TRACE_GRAPH_PRINT_IRQS 0x40
+#define TRACE_GRAPH_PRINT_TAIL 0x80
#define TRACE_GRAPH_PRINT_FILL_SHIFT 28
#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
@@ -823,6 +828,10 @@ extern int ftrace_is_dead(void);
int ftrace_create_function_files(struct trace_array *tr,
struct dentry *parent);
void ftrace_destroy_function_files(struct trace_array *tr);
+void ftrace_init_global_array_ops(struct trace_array *tr);
+void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
+void ftrace_reset_array_ops(struct trace_array *tr);
+int using_ftrace_ops_list_func(void);
#else
static inline int ftrace_trace_task(struct task_struct *task)
{
@@ -836,6 +845,11 @@ ftrace_create_function_files(struct trace_array *tr,
return 0;
}
static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
+static inline __init void
+ftrace_init_global_array_ops(struct trace_array *tr) { }
+static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
+/* ftace_func_t type is not defined, use macro instead of static inline */
+#define ftrace_init_array_ops(tr, func) do { } while (0)
#endif /* CONFIG_FUNCTION_TRACER */
#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
diff --git a/kernel/trace/trace_benchmark.c b/kernel/trace/trace_benchmark.c
new file mode 100644
index 000000000000..40a14cbcf8e0
--- /dev/null
+++ b/kernel/trace/trace_benchmark.c
@@ -0,0 +1,198 @@
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/trace_clock.h>
+
+#define CREATE_TRACE_POINTS
+#include "trace_benchmark.h"
+
+static struct task_struct *bm_event_thread;
+
+static char bm_str[BENCHMARK_EVENT_STRLEN] = "START";
+
+static u64 bm_total;
+static u64 bm_totalsq;
+static u64 bm_last;
+static u64 bm_max;
+static u64 bm_min;
+static u64 bm_first;
+static u64 bm_cnt;
+static u64 bm_stddev;
+static unsigned int bm_avg;
+static unsigned int bm_std;
+
+/*
+ * This gets called in a loop recording the time it took to write
+ * the tracepoint. What it writes is the time statistics of the last
+ * tracepoint write. As there is nothing to write the first time
+ * it simply writes "START". As the first write is cold cache and
+ * the rest is hot, we save off that time in bm_first and it is
+ * reported as "first", which is shown in the second write to the
+ * tracepoint. The "first" field is writen within the statics from
+ * then on but never changes.
+ */
+static void trace_do_benchmark(void)
+{
+ u64 start;
+ u64 stop;
+ u64 delta;
+ u64 stddev;
+ u64 seed;
+ u64 last_seed;
+ unsigned int avg;
+ unsigned int std = 0;
+
+ /* Only run if the tracepoint is actually active */
+ if (!trace_benchmark_event_enabled())
+ return;
+
+ local_irq_disable();
+ start = trace_clock_local();
+ trace_benchmark_event(bm_str);
+ stop = trace_clock_local();
+ local_irq_enable();
+
+ bm_cnt++;
+
+ delta = stop - start;
+
+ /*
+ * The first read is cold cached, keep it separate from the
+ * other calculations.
+ */
+ if (bm_cnt == 1) {
+ bm_first = delta;
+ scnprintf(bm_str, BENCHMARK_EVENT_STRLEN,
+ "first=%llu [COLD CACHED]", bm_first);
+ return;
+ }
+
+ bm_last = delta;
+
+ if (delta > bm_max)
+ bm_max = delta;
+ if (!bm_min || delta < bm_min)
+ bm_min = delta;
+
+ /*
+ * When bm_cnt is greater than UINT_MAX, it breaks the statistics
+ * accounting. Freeze the statistics when that happens.
+ * We should have enough data for the avg and stddev anyway.
+ */
+ if (bm_cnt > UINT_MAX) {
+ scnprintf(bm_str, BENCHMARK_EVENT_STRLEN,
+ "last=%llu first=%llu max=%llu min=%llu ** avg=%u std=%d std^2=%lld",
+ bm_last, bm_first, bm_max, bm_min, bm_avg, bm_std, bm_stddev);
+ return;
+ }
+
+ bm_total += delta;
+ bm_totalsq += delta * delta;
+
+
+ if (bm_cnt > 1) {
+ /*
+ * Apply Welford's method to calculate standard deviation:
+ * s^2 = 1 / (n * (n-1)) * (n * \Sum (x_i)^2 - (\Sum x_i)^2)
+ */
+ stddev = (u64)bm_cnt * bm_totalsq - bm_total * bm_total;
+ do_div(stddev, (u32)bm_cnt);
+ do_div(stddev, (u32)bm_cnt - 1);
+ } else
+ stddev = 0;
+
+ delta = bm_total;
+ do_div(delta, bm_cnt);
+ avg = delta;
+
+ if (stddev > 0) {
+ int i = 0;
+ /*
+ * stddev is the square of standard deviation but
+ * we want the actualy number. Use the average
+ * as our seed to find the std.
+ *
+ * The next try is:
+ * x = (x + N/x) / 2
+ *
+ * Where N is the squared number to find the square
+ * root of.
+ */
+ seed = avg;
+ do {
+ last_seed = seed;
+ seed = stddev;
+ if (!last_seed)
+ break;
+ do_div(seed, last_seed);
+ seed += last_seed;
+ do_div(seed, 2);
+ } while (i++ < 10 && last_seed != seed);
+
+ std = seed;
+ }
+
+ scnprintf(bm_str, BENCHMARK_EVENT_STRLEN,
+ "last=%llu first=%llu max=%llu min=%llu avg=%u std=%d std^2=%lld",
+ bm_last, bm_first, bm_max, bm_min, avg, std, stddev);
+
+ bm_std = std;
+ bm_avg = avg;
+ bm_stddev = stddev;
+}
+
+static int benchmark_event_kthread(void *arg)
+{
+ /* sleep a bit to make sure the tracepoint gets activated */
+ msleep(100);
+
+ while (!kthread_should_stop()) {
+
+ trace_do_benchmark();
+
+ /*
+ * We don't go to sleep, but let others
+ * run as well.
+ */
+ cond_resched();
+ }
+
+ return 0;
+}
+
+/*
+ * When the benchmark tracepoint is enabled, it calls this
+ * function and the thread that calls the tracepoint is created.
+ */
+void trace_benchmark_reg(void)
+{
+ bm_event_thread = kthread_run(benchmark_event_kthread,
+ NULL, "event_benchmark");
+ WARN_ON(!bm_event_thread);
+}
+
+/*
+ * When the benchmark tracepoint is disabled, it calls this
+ * function and the thread that calls the tracepoint is deleted
+ * and all the numbers are reset.
+ */
+void trace_benchmark_unreg(void)
+{
+ if (!bm_event_thread)
+ return;
+
+ kthread_stop(bm_event_thread);
+
+ strcpy(bm_str, "START");
+ bm_total = 0;
+ bm_totalsq = 0;
+ bm_last = 0;
+ bm_max = 0;
+ bm_min = 0;
+ bm_cnt = 0;
+ /* These don't need to be reset but reset them anyway */
+ bm_first = 0;
+ bm_std = 0;
+ bm_avg = 0;
+ bm_stddev = 0;
+}
diff --git a/kernel/trace/trace_benchmark.h b/kernel/trace/trace_benchmark.h
new file mode 100644
index 000000000000..3c1df1df4e29
--- /dev/null
+++ b/kernel/trace/trace_benchmark.h
@@ -0,0 +1,41 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM benchmark
+
+#if !defined(_TRACE_BENCHMARK_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_BENCHMARK_H
+
+#include <linux/tracepoint.h>
+
+extern void trace_benchmark_reg(void);
+extern void trace_benchmark_unreg(void);
+
+#define BENCHMARK_EVENT_STRLEN 128
+
+TRACE_EVENT_FN(benchmark_event,
+
+ TP_PROTO(const char *str),
+
+ TP_ARGS(str),
+
+ TP_STRUCT__entry(
+ __array( char, str, BENCHMARK_EVENT_STRLEN )
+ ),
+
+ TP_fast_assign(
+ memcpy(__entry->str, str, BENCHMARK_EVENT_STRLEN);
+ ),
+
+ TP_printk("%s", __entry->str),
+
+ trace_benchmark_reg, trace_benchmark_unreg
+);
+
+#endif /* _TRACE_BENCHMARK_H */
+
+#undef TRACE_INCLUDE_FILE
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE trace_benchmark
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 3ddfd8f62c05..f99e0b3bca8c 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -574,6 +574,9 @@ int trace_set_clr_event(const char *system, const char *event, int set)
{
struct trace_array *tr = top_trace_array();
+ if (!tr)
+ return -ENODEV;
+
return __ftrace_set_clr_event(tr, NULL, system, event, set);
}
EXPORT_SYMBOL_GPL(trace_set_clr_event);
@@ -2065,6 +2068,9 @@ event_enable_func(struct ftrace_hash *hash,
bool enable;
int ret;
+ if (!tr)
+ return -ENODEV;
+
/* hash funcs only work with set_ftrace_filter */
if (!enabled || !param)
return -EINVAL;
@@ -2396,6 +2402,9 @@ static __init int event_trace_enable(void)
char *token;
int ret;
+ if (!tr)
+ return -ENODEV;
+
for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) {
call = *iter;
@@ -2442,6 +2451,8 @@ static __init int event_trace_init(void)
int ret;
tr = top_trace_array();
+ if (!tr)
+ return -ENODEV;
d_tracer = tracing_init_dentry();
if (!d_tracer)
@@ -2535,6 +2546,8 @@ static __init void event_trace_self_tests(void)
int ret;
tr = top_trace_array();
+ if (!tr)
+ return;
pr_info("Running tests on trace events:\n");
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index ffd56351b521..57f0ec962d2c 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -26,8 +26,6 @@ function_trace_call(unsigned long ip, unsigned long parent_ip,
static void
function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *pt_regs);
-static struct ftrace_ops trace_ops;
-static struct ftrace_ops trace_stack_ops;
static struct tracer_flags func_flags;
/* Our option */
@@ -83,28 +81,24 @@ void ftrace_destroy_function_files(struct trace_array *tr)
static int function_trace_init(struct trace_array *tr)
{
- struct ftrace_ops *ops;
-
- if (tr->flags & TRACE_ARRAY_FL_GLOBAL) {
- /* There's only one global tr */
- if (!trace_ops.private) {
- trace_ops.private = tr;
- trace_stack_ops.private = tr;
- }
+ ftrace_func_t func;
- if (func_flags.val & TRACE_FUNC_OPT_STACK)
- ops = &trace_stack_ops;
- else
- ops = &trace_ops;
- tr->ops = ops;
- } else if (!tr->ops) {
- /*
- * Instance trace_arrays get their ops allocated
- * at instance creation. Unless it failed
- * the allocation.
- */
+ /*
+ * Instance trace_arrays get their ops allocated
+ * at instance creation. Unless it failed
+ * the allocation.
+ */
+ if (!tr->ops)
return -ENOMEM;
- }
+
+ /* Currently only the global instance can do stack tracing */
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL &&
+ func_flags.val & TRACE_FUNC_OPT_STACK)
+ func = function_stack_trace_call;
+ else
+ func = function_trace_call;
+
+ ftrace_init_array_ops(tr, func);
tr->trace_buffer.cpu = get_cpu();
put_cpu();
@@ -118,6 +112,7 @@ static void function_trace_reset(struct trace_array *tr)
{
tracing_stop_function_trace(tr);
tracing_stop_cmdline_record();
+ ftrace_reset_array_ops(tr);
}
static void function_trace_start(struct trace_array *tr)
@@ -199,18 +194,6 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
local_irq_restore(flags);
}
-static struct ftrace_ops trace_ops __read_mostly =
-{
- .func = function_trace_call,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
-static struct ftrace_ops trace_stack_ops __read_mostly =
-{
- .func = function_stack_trace_call,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
static struct tracer_opt func_opts[] = {
#ifdef CONFIG_STACKTRACE
{ TRACER_OPT(func_stack_trace, TRACE_FUNC_OPT_STACK) },
@@ -248,10 +231,10 @@ func_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
unregister_ftrace_function(tr->ops);
if (set) {
- tr->ops = &trace_stack_ops;
+ tr->ops->func = function_stack_trace_call;
register_ftrace_function(tr->ops);
} else {
- tr->ops = &trace_ops;
+ tr->ops->func = function_trace_call;
register_ftrace_function(tr->ops);
}
@@ -269,7 +252,6 @@ static struct tracer function_trace __tracer_data =
.init = function_trace_init,
.reset = function_trace_reset,
.start = function_trace_start,
- .wait_pipe = poll_wait_pipe,
.flags = &func_flags,
.set_flag = func_set_flag,
.allow_instances = true,
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index deff11200261..4de3e57f723c 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -38,15 +38,6 @@ struct fgraph_data {
#define TRACE_GRAPH_INDENT 2
-/* Flag options */
-#define TRACE_GRAPH_PRINT_OVERRUN 0x1
-#define TRACE_GRAPH_PRINT_CPU 0x2
-#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
-#define TRACE_GRAPH_PRINT_PROC 0x8
-#define TRACE_GRAPH_PRINT_DURATION 0x10
-#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
-#define TRACE_GRAPH_PRINT_IRQS 0x40
-
static unsigned int max_depth;
static struct tracer_opt trace_opts[] = {
@@ -64,11 +55,13 @@ static struct tracer_opt trace_opts[] = {
{ TRACER_OPT(funcgraph-abstime, TRACE_GRAPH_PRINT_ABS_TIME) },
/* Display interrupts */
{ TRACER_OPT(funcgraph-irqs, TRACE_GRAPH_PRINT_IRQS) },
+ /* Display function name after trailing } */
+ { TRACER_OPT(funcgraph-tail, TRACE_GRAPH_PRINT_TAIL) },
{ } /* Empty entry */
};
static struct tracer_flags tracer_flags = {
- /* Don't display overruns and proc by default */
+ /* Don't display overruns, proc, or tail by default */
.val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD |
TRACE_GRAPH_PRINT_DURATION | TRACE_GRAPH_PRINT_IRQS,
.opts = trace_opts
@@ -1176,9 +1169,10 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
* If the return function does not have a matching entry,
* then the entry was lost. Instead of just printing
* the '}' and letting the user guess what function this
- * belongs to, write out the function name.
+ * belongs to, write out the function name. Always do
+ * that if the funcgraph-tail option is enabled.
*/
- if (func_match) {
+ if (func_match && !(flags & TRACE_GRAPH_PRINT_TAIL)) {
ret = trace_seq_puts(s, "}\n");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
@@ -1505,7 +1499,6 @@ static struct tracer graph_trace __tracer_data = {
.pipe_open = graph_trace_open,
.close = graph_trace_close,
.pipe_close = graph_trace_close,
- .wait_pipe = poll_wait_pipe,
.init = graph_trace_init,
.reset = graph_trace_reset,
.print_line = print_graph_function,
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 8ff02cbb892f..9bb104f748d0 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -151,12 +151,6 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip,
atomic_dec(&data->disabled);
}
-
-static struct ftrace_ops trace_ops __read_mostly =
-{
- .func = irqsoff_tracer_call,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
#endif /* CONFIG_FUNCTION_TRACER */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -176,7 +170,7 @@ irqsoff_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
for_each_possible_cpu(cpu)
per_cpu(tracing_cpu, cpu) = 0;
- tracing_max_latency = 0;
+ tr->max_latency = 0;
tracing_reset_online_cpus(&irqsoff_trace->trace_buffer);
return start_irqsoff_tracer(irqsoff_trace, set);
@@ -303,13 +297,13 @@ static void irqsoff_print_header(struct seq_file *s)
/*
* Should this new latency be reported/recorded?
*/
-static int report_latency(cycle_t delta)
+static int report_latency(struct trace_array *tr, cycle_t delta)
{
if (tracing_thresh) {
if (delta < tracing_thresh)
return 0;
} else {
- if (delta <= tracing_max_latency)
+ if (delta <= tr->max_latency)
return 0;
}
return 1;
@@ -333,13 +327,13 @@ check_critical_timing(struct trace_array *tr,
pc = preempt_count();
- if (!report_latency(delta))
+ if (!report_latency(tr, delta))
goto out;
raw_spin_lock_irqsave(&max_trace_lock, flags);
/* check if we are still the max latency */
- if (!report_latency(delta))
+ if (!report_latency(tr, delta))
goto out_unlock;
__trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
@@ -352,7 +346,7 @@ check_critical_timing(struct trace_array *tr,
data->critical_end = parent_ip;
if (likely(!is_tracing_stopped())) {
- tracing_max_latency = delta;
+ tr->max_latency = delta;
update_max_tr_single(tr, current, cpu);
}
@@ -531,7 +525,7 @@ void trace_preempt_off(unsigned long a0, unsigned long a1)
}
#endif /* CONFIG_PREEMPT_TRACER */
-static int register_irqsoff_function(int graph, int set)
+static int register_irqsoff_function(struct trace_array *tr, int graph, int set)
{
int ret;
@@ -543,7 +537,7 @@ static int register_irqsoff_function(int graph, int set)
ret = register_ftrace_graph(&irqsoff_graph_return,
&irqsoff_graph_entry);
else
- ret = register_ftrace_function(&trace_ops);
+ ret = register_ftrace_function(tr->ops);
if (!ret)
function_enabled = true;
@@ -551,7 +545,7 @@ static int register_irqsoff_function(int graph, int set)
return ret;
}
-static void unregister_irqsoff_function(int graph)
+static void unregister_irqsoff_function(struct trace_array *tr, int graph)
{
if (!function_enabled)
return;
@@ -559,17 +553,17 @@ static void unregister_irqsoff_function(int graph)
if (graph)
unregister_ftrace_graph();
else
- unregister_ftrace_function(&trace_ops);
+ unregister_ftrace_function(tr->ops);
function_enabled = false;
}
-static void irqsoff_function_set(int set)
+static void irqsoff_function_set(struct trace_array *tr, int set)
{
if (set)
- register_irqsoff_function(is_graph(), 1);
+ register_irqsoff_function(tr, is_graph(), 1);
else
- unregister_irqsoff_function(is_graph());
+ unregister_irqsoff_function(tr, is_graph());
}
static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set)
@@ -577,7 +571,7 @@ static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set)
struct tracer *tracer = tr->current_trace;
if (mask & TRACE_ITER_FUNCTION)
- irqsoff_function_set(set);
+ irqsoff_function_set(tr, set);
return trace_keep_overwrite(tracer, mask, set);
}
@@ -586,7 +580,7 @@ static int start_irqsoff_tracer(struct trace_array *tr, int graph)
{
int ret;
- ret = register_irqsoff_function(graph, 0);
+ ret = register_irqsoff_function(tr, graph, 0);
if (!ret && tracing_is_enabled())
tracer_enabled = 1;
@@ -600,25 +594,37 @@ static void stop_irqsoff_tracer(struct trace_array *tr, int graph)
{
tracer_enabled = 0;
- unregister_irqsoff_function(graph);
+ unregister_irqsoff_function(tr, graph);
}
-static void __irqsoff_tracer_init(struct trace_array *tr)
+static bool irqsoff_busy;
+
+static int __irqsoff_tracer_init(struct trace_array *tr)
{
+ if (irqsoff_busy)
+ return -EBUSY;
+
save_flags = trace_flags;
/* non overwrite screws up the latency tracers */
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1);
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1);
- tracing_max_latency = 0;
+ tr->max_latency = 0;
irqsoff_trace = tr;
/* make sure that the tracer is visible */
smp_wmb();
tracing_reset_online_cpus(&tr->trace_buffer);
- if (start_irqsoff_tracer(tr, is_graph()))
+ ftrace_init_array_ops(tr, irqsoff_tracer_call);
+
+ /* Only toplevel instance supports graph tracing */
+ if (start_irqsoff_tracer(tr, (tr->flags & TRACE_ARRAY_FL_GLOBAL &&
+ is_graph())))
printk(KERN_ERR "failed to start irqsoff tracer\n");
+
+ irqsoff_busy = true;
+ return 0;
}
static void irqsoff_tracer_reset(struct trace_array *tr)
@@ -630,6 +636,9 @@ static void irqsoff_tracer_reset(struct trace_array *tr)
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag);
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag);
+ ftrace_reset_array_ops(tr);
+
+ irqsoff_busy = false;
}
static void irqsoff_tracer_start(struct trace_array *tr)
@@ -647,8 +656,7 @@ static int irqsoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_IRQS_OFF;
- __irqsoff_tracer_init(tr);
- return 0;
+ return __irqsoff_tracer_init(tr);
}
static struct tracer irqsoff_tracer __read_mostly =
{
@@ -668,6 +676,7 @@ static struct tracer irqsoff_tracer __read_mostly =
#endif
.open = irqsoff_trace_open,
.close = irqsoff_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
# define register_irqsoff(trace) register_tracer(&trace)
@@ -680,8 +689,7 @@ static int preemptoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_PREEMPT_OFF;
- __irqsoff_tracer_init(tr);
- return 0;
+ return __irqsoff_tracer_init(tr);
}
static struct tracer preemptoff_tracer __read_mostly =
@@ -702,6 +710,7 @@ static struct tracer preemptoff_tracer __read_mostly =
#endif
.open = irqsoff_trace_open,
.close = irqsoff_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
# define register_preemptoff(trace) register_tracer(&trace)
@@ -716,8 +725,7 @@ static int preemptirqsoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_IRQS_OFF | TRACER_PREEMPT_OFF;
- __irqsoff_tracer_init(tr);
- return 0;
+ return __irqsoff_tracer_init(tr);
}
static struct tracer preemptirqsoff_tracer __read_mostly =
@@ -738,6 +746,7 @@ static struct tracer preemptirqsoff_tracer __read_mostly =
#endif
.open = irqsoff_trace_open,
.close = irqsoff_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 903ae28962be..ef2fba1f46b5 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1377,6 +1377,9 @@ static __init int kprobe_trace_self_tests_init(void)
struct trace_kprobe *tk;
struct ftrace_event_file *file;
+ if (tracing_is_disabled())
+ return -ENODEV;
+
target = kprobe_trace_selftest_target;
pr_info("Testing kprobe tracing: ");
diff --git a/kernel/trace/trace_nop.c b/kernel/trace/trace_nop.c
index 69a5cc94c01a..fcf0a9e48916 100644
--- a/kernel/trace/trace_nop.c
+++ b/kernel/trace/trace_nop.c
@@ -91,7 +91,6 @@ struct tracer nop_trace __read_mostly =
.name = "nop",
.init = nop_trace_init,
.reset = nop_trace_reset,
- .wait_pipe = poll_wait_pipe,
#ifdef CONFIG_FTRACE_SELFTEST
.selftest = trace_selftest_startup_nop,
#endif
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index a436de18aa99..f3dad80c20b2 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -126,6 +126,34 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
EXPORT_SYMBOL_GPL(trace_seq_printf);
/**
+ * trace_seq_bitmask - put a list of longs as a bitmask print output
+ * @s: trace sequence descriptor
+ * @maskp: points to an array of unsigned longs that represent a bitmask
+ * @nmaskbits: The number of bits that are valid in @maskp
+ *
+ * It returns 0 if the trace oversizes the buffer's free
+ * space, 1 otherwise.
+ *
+ * Writes a ASCII representation of a bitmask string into @s.
+ */
+int
+trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
+ int nmaskbits)
+{
+ int len = (PAGE_SIZE - 1) - s->len;
+ int ret;
+
+ if (s->full || !len)
+ return 0;
+
+ ret = bitmap_scnprintf(s->buffer, len, maskp, nmaskbits);
+ s->len += ret;
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(trace_seq_bitmask);
+
+/**
* trace_seq_vprintf - sequence printing of trace information
* @s: trace sequence descriptor
* @fmt: printf format string
@@ -399,6 +427,19 @@ EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
#endif
const char *
+ftrace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
+ unsigned int bitmask_size)
+{
+ const char *ret = p->buffer + p->len;
+
+ trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8);
+ trace_seq_putc(p, 0);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ftrace_print_bitmask_seq);
+
+const char *
ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
{
int i;
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index e14da5e97a69..19bd8928ce94 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -130,15 +130,9 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip,
atomic_dec(&data->disabled);
preempt_enable_notrace();
}
-
-static struct ftrace_ops trace_ops __read_mostly =
-{
- .func = wakeup_tracer_call,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
#endif /* CONFIG_FUNCTION_TRACER */
-static int register_wakeup_function(int graph, int set)
+static int register_wakeup_function(struct trace_array *tr, int graph, int set)
{
int ret;
@@ -150,7 +144,7 @@ static int register_wakeup_function(int graph, int set)
ret = register_ftrace_graph(&wakeup_graph_return,
&wakeup_graph_entry);
else
- ret = register_ftrace_function(&trace_ops);
+ ret = register_ftrace_function(tr->ops);
if (!ret)
function_enabled = true;
@@ -158,7 +152,7 @@ static int register_wakeup_function(int graph, int set)
return ret;
}
-static void unregister_wakeup_function(int graph)
+static void unregister_wakeup_function(struct trace_array *tr, int graph)
{
if (!function_enabled)
return;
@@ -166,17 +160,17 @@ static void unregister_wakeup_function(int graph)
if (graph)
unregister_ftrace_graph();
else
- unregister_ftrace_function(&trace_ops);
+ unregister_ftrace_function(tr->ops);
function_enabled = false;
}
-static void wakeup_function_set(int set)
+static void wakeup_function_set(struct trace_array *tr, int set)
{
if (set)
- register_wakeup_function(is_graph(), 1);
+ register_wakeup_function(tr, is_graph(), 1);
else
- unregister_wakeup_function(is_graph());
+ unregister_wakeup_function(tr, is_graph());
}
static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
@@ -184,16 +178,16 @@ static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
struct tracer *tracer = tr->current_trace;
if (mask & TRACE_ITER_FUNCTION)
- wakeup_function_set(set);
+ wakeup_function_set(tr, set);
return trace_keep_overwrite(tracer, mask, set);
}
-static int start_func_tracer(int graph)
+static int start_func_tracer(struct trace_array *tr, int graph)
{
int ret;
- ret = register_wakeup_function(graph, 0);
+ ret = register_wakeup_function(tr, graph, 0);
if (!ret && tracing_is_enabled())
tracer_enabled = 1;
@@ -203,11 +197,11 @@ static int start_func_tracer(int graph)
return ret;
}
-static void stop_func_tracer(int graph)
+static void stop_func_tracer(struct trace_array *tr, int graph)
{
tracer_enabled = 0;
- unregister_wakeup_function(graph);
+ unregister_wakeup_function(tr, graph);
}
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -221,12 +215,12 @@ wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
if (!(is_graph() ^ set))
return 0;
- stop_func_tracer(!set);
+ stop_func_tracer(tr, !set);
wakeup_reset(wakeup_trace);
- tracing_max_latency = 0;
+ tr->max_latency = 0;
- return start_func_tracer(set);
+ return start_func_tracer(tr, set);
}
static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
@@ -350,13 +344,13 @@ static void wakeup_print_header(struct seq_file *s)
/*
* Should this new latency be reported/recorded?
*/
-static int report_latency(cycle_t delta)
+static int report_latency(struct trace_array *tr, cycle_t delta)
{
if (tracing_thresh) {
if (delta < tracing_thresh)
return 0;
} else {
- if (delta <= tracing_max_latency)
+ if (delta <= tr->max_latency)
return 0;
}
return 1;
@@ -424,11 +418,11 @@ probe_wakeup_sched_switch(void *ignore,
T1 = ftrace_now(cpu);
delta = T1-T0;
- if (!report_latency(delta))
+ if (!report_latency(wakeup_trace, delta))
goto out_unlock;
if (likely(!is_tracing_stopped())) {
- tracing_max_latency = delta;
+ wakeup_trace->max_latency = delta;
update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
}
@@ -587,7 +581,7 @@ static void start_wakeup_tracer(struct trace_array *tr)
*/
smp_wmb();
- if (start_func_tracer(is_graph()))
+ if (start_func_tracer(tr, is_graph()))
printk(KERN_ERR "failed to start wakeup tracer\n");
return;
@@ -600,13 +594,15 @@ fail_deprobe:
static void stop_wakeup_tracer(struct trace_array *tr)
{
tracer_enabled = 0;
- stop_func_tracer(is_graph());
+ stop_func_tracer(tr, is_graph());
unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL);
unregister_trace_sched_wakeup_new(probe_wakeup, NULL);
unregister_trace_sched_wakeup(probe_wakeup, NULL);
unregister_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL);
}
+static bool wakeup_busy;
+
static int __wakeup_tracer_init(struct trace_array *tr)
{
save_flags = trace_flags;
@@ -615,14 +611,20 @@ static int __wakeup_tracer_init(struct trace_array *tr)
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1);
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1);
- tracing_max_latency = 0;
+ tr->max_latency = 0;
wakeup_trace = tr;
+ ftrace_init_array_ops(tr, wakeup_tracer_call);
start_wakeup_tracer(tr);
+
+ wakeup_busy = true;
return 0;
}
static int wakeup_tracer_init(struct trace_array *tr)
{
+ if (wakeup_busy)
+ return -EBUSY;
+
wakeup_dl = 0;
wakeup_rt = 0;
return __wakeup_tracer_init(tr);
@@ -630,6 +632,9 @@ static int wakeup_tracer_init(struct trace_array *tr)
static int wakeup_rt_tracer_init(struct trace_array *tr)
{
+ if (wakeup_busy)
+ return -EBUSY;
+
wakeup_dl = 0;
wakeup_rt = 1;
return __wakeup_tracer_init(tr);
@@ -637,6 +642,9 @@ static int wakeup_rt_tracer_init(struct trace_array *tr)
static int wakeup_dl_tracer_init(struct trace_array *tr)
{
+ if (wakeup_busy)
+ return -EBUSY;
+
wakeup_dl = 1;
wakeup_rt = 0;
return __wakeup_tracer_init(tr);
@@ -653,6 +661,8 @@ static void wakeup_tracer_reset(struct trace_array *tr)
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag);
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag);
+ ftrace_reset_array_ops(tr);
+ wakeup_busy = false;
}
static void wakeup_tracer_start(struct trace_array *tr)
@@ -684,6 +694,7 @@ static struct tracer wakeup_tracer __read_mostly =
#endif
.open = wakeup_trace_open,
.close = wakeup_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
@@ -694,7 +705,6 @@ static struct tracer wakeup_rt_tracer __read_mostly =
.reset = wakeup_tracer_reset,
.start = wakeup_tracer_start,
.stop = wakeup_tracer_stop,
- .wait_pipe = poll_wait_pipe,
.print_max = true,
.print_header = wakeup_print_header,
.print_line = wakeup_print_line,
@@ -706,6 +716,7 @@ static struct tracer wakeup_rt_tracer __read_mostly =
#endif
.open = wakeup_trace_open,
.close = wakeup_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
@@ -716,7 +727,6 @@ static struct tracer wakeup_dl_tracer __read_mostly =
.reset = wakeup_tracer_reset,
.start = wakeup_tracer_start,
.stop = wakeup_tracer_stop,
- .wait_pipe = poll_wait_pipe,
.print_max = true,
.print_header = wakeup_print_header,
.print_line = wakeup_print_line,
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index e98fca60974f..5ef60499dc8e 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -65,7 +65,7 @@ static int trace_test_buffer(struct trace_buffer *buf, unsigned long *count)
/* Don't allow flipping of max traces now */
local_irq_save(flags);
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&buf->tr->max_lock);
cnt = ring_buffer_entries(buf->buffer);
@@ -83,7 +83,7 @@ static int trace_test_buffer(struct trace_buffer *buf, unsigned long *count)
break;
}
tracing_on();
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&buf->tr->max_lock);
local_irq_restore(flags);
if (count)
@@ -161,11 +161,6 @@ static struct ftrace_ops test_probe3 = {
.flags = FTRACE_OPS_FL_RECURSION_SAFE,
};
-static struct ftrace_ops test_global = {
- .func = trace_selftest_test_global_func,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
static void print_counts(void)
{
printk("(%d %d %d %d %d) ",
@@ -185,7 +180,7 @@ static void reset_counts(void)
trace_selftest_test_dyn_cnt = 0;
}
-static int trace_selftest_ops(int cnt)
+static int trace_selftest_ops(struct trace_array *tr, int cnt)
{
int save_ftrace_enabled = ftrace_enabled;
struct ftrace_ops *dyn_ops;
@@ -220,7 +215,11 @@ static int trace_selftest_ops(int cnt)
register_ftrace_function(&test_probe1);
register_ftrace_function(&test_probe2);
register_ftrace_function(&test_probe3);
- register_ftrace_function(&test_global);
+ /* First time we are running with main function */
+ if (cnt > 1) {
+ ftrace_init_array_ops(tr, trace_selftest_test_global_func);
+ register_ftrace_function(tr->ops);
+ }
DYN_FTRACE_TEST_NAME();
@@ -232,8 +231,10 @@ static int trace_selftest_ops(int cnt)
goto out;
if (trace_selftest_test_probe3_cnt != 1)
goto out;
- if (trace_selftest_test_global_cnt == 0)
- goto out;
+ if (cnt > 1) {
+ if (trace_selftest_test_global_cnt == 0)
+ goto out;
+ }
DYN_FTRACE_TEST_NAME2();
@@ -269,8 +270,10 @@ static int trace_selftest_ops(int cnt)
goto out_free;
if (trace_selftest_test_probe3_cnt != 3)
goto out_free;
- if (trace_selftest_test_global_cnt == 0)
- goto out;
+ if (cnt > 1) {
+ if (trace_selftest_test_global_cnt == 0)
+ goto out;
+ }
if (trace_selftest_test_dyn_cnt == 0)
goto out_free;
@@ -295,7 +298,9 @@ static int trace_selftest_ops(int cnt)
unregister_ftrace_function(&test_probe1);
unregister_ftrace_function(&test_probe2);
unregister_ftrace_function(&test_probe3);
- unregister_ftrace_function(&test_global);
+ if (cnt > 1)
+ unregister_ftrace_function(tr->ops);
+ ftrace_reset_array_ops(tr);
/* Make sure everything is off */
reset_counts();
@@ -315,9 +320,9 @@ static int trace_selftest_ops(int cnt)
}
/* Test dynamic code modification and ftrace filters */
-int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
- struct trace_array *tr,
- int (*func)(void))
+static int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
+ struct trace_array *tr,
+ int (*func)(void))
{
int save_ftrace_enabled = ftrace_enabled;
unsigned long count;
@@ -388,7 +393,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
}
/* Test the ops with global tracing running */
- ret = trace_selftest_ops(1);
+ ret = trace_selftest_ops(tr, 1);
trace->reset(tr);
out:
@@ -399,7 +404,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
/* Test the ops with global tracing off */
if (!ret)
- ret = trace_selftest_ops(2);
+ ret = trace_selftest_ops(tr, 2);
return ret;
}
@@ -802,7 +807,7 @@ out:
int
trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
unsigned long count;
int ret;
@@ -814,7 +819,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
}
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
/* disable interrupts for a bit */
local_irq_disable();
udelay(100);
@@ -841,7 +846,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
ret = -1;
}
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
return ret;
}
@@ -851,7 +856,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
int
trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
unsigned long count;
int ret;
@@ -876,7 +881,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
}
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
/* disable preemption for a bit */
preempt_disable();
udelay(100);
@@ -903,7 +908,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
ret = -1;
}
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
return ret;
}
@@ -913,7 +918,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
int
trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
unsigned long count;
int ret;
@@ -938,7 +943,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
}
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
/* disable preemption and interrupts for a bit */
preempt_disable();
@@ -973,7 +978,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
}
/* do the test by disabling interrupts first this time */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
tracing_start();
trace->start(tr);
@@ -1004,7 +1009,7 @@ out:
tracing_start();
out_no_start:
trace->reset(tr);
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
return ret;
}
@@ -1057,7 +1062,7 @@ static int trace_wakeup_test_thread(void *data)
int
trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
struct task_struct *p;
struct completion is_ready;
unsigned long count;
@@ -1083,7 +1088,7 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
}
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
while (p->on_rq) {
/*
@@ -1113,7 +1118,7 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
trace->reset(tr);
tracing_start();
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
/* kill the thread */
kthread_stop(p);
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 21b320e5d163..8a4e5cb66a4c 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -51,11 +51,33 @@ static DEFINE_MUTEX(stack_sysctl_mutex);
int stack_tracer_enabled;
static int last_stack_tracer_enabled;
+static inline void print_max_stack(void)
+{
+ long i;
+ int size;
+
+ pr_emerg(" Depth Size Location (%d entries)\n"
+ " ----- ---- --------\n",
+ max_stack_trace.nr_entries - 1);
+
+ for (i = 0; i < max_stack_trace.nr_entries; i++) {
+ if (stack_dump_trace[i] == ULONG_MAX)
+ break;
+ if (i+1 == max_stack_trace.nr_entries ||
+ stack_dump_trace[i+1] == ULONG_MAX)
+ size = stack_dump_index[i];
+ else
+ size = stack_dump_index[i] - stack_dump_index[i+1];
+
+ pr_emerg("%3ld) %8d %5d %pS\n", i, stack_dump_index[i],
+ size, (void *)stack_dump_trace[i]);
+ }
+}
+
static inline void
check_stack(unsigned long ip, unsigned long *stack)
{
- unsigned long this_size, flags;
- unsigned long *p, *top, *start;
+ unsigned long this_size, flags; unsigned long *p, *top, *start;
static int tracer_frame;
int frame_size = ACCESS_ONCE(tracer_frame);
int i;
@@ -85,8 +107,12 @@ check_stack(unsigned long ip, unsigned long *stack)
max_stack_size = this_size;
- max_stack_trace.nr_entries = 0;
- max_stack_trace.skip = 3;
+ max_stack_trace.nr_entries = 0;
+
+ if (using_ftrace_ops_list_func())
+ max_stack_trace.skip = 4;
+ else
+ max_stack_trace.skip = 3;
save_stack_trace(&max_stack_trace);
@@ -145,8 +171,12 @@ check_stack(unsigned long ip, unsigned long *stack)
i++;
}
- BUG_ON(current != &init_task &&
- *(end_of_stack(current)) != STACK_END_MAGIC);
+ if ((current != &init_task &&
+ *(end_of_stack(current)) != STACK_END_MAGIC)) {
+ print_max_stack();
+ BUG();
+ }
+
out:
arch_spin_unlock(&max_stack_lock);
local_irq_restore(flags);