Commit a40694a3 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'perfcounters-fixes-for-linus' of... 

Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf_counter: Set the CONFIG_PERF_COUNTERS default to y if CONFIG_PROFILING=y
  perf: Fix read buffer overflow
  perf top: Add mwait_idle_with_hints to skip_symbols[]
  perf tools: Fix faulty check
  perf report: Update for the new FORK/EXIT events
  perf_counter: Full task tracing
  perf_counter: Collapse inherit on read()
  tracing, perf_counter: Add help text to CONFIG_EVENT_PROFILE
  perf_counter tools: Fix link errors with older toolchains
parents ea563424 f2654260

include/linux/perf_counter.h

+12 −1
Original line number Diff line number Diff line
@@ -181,8 +181,9 @@ struct perf_counter_attr { 
				freq           :  1, /* use freq, not period  */

				inherit_stat   :  1, /* per task counts       */

				enable_on_exec :  1, /* next exec enables     */

				task           :  1, /* trace fork/exit       */



				__reserved_1   : 51;

				__reserved_1   : 50;



	__u32			wakeup_events;	/* wakeup every n events */

	__u32			__reserved_2;
@@ -308,6 +309,15 @@ enum perf_event_type { 
	 */

	PERF_EVENT_COMM			= 3,



	/*

	 * struct {

	 *	struct perf_event_header	header;

	 *	u32				pid, ppid;

	 *	u32				tid, ptid;

	 * };

	 */

	PERF_EVENT_EXIT			= 4,



	/*

	 * struct {

	 *	struct perf_event_header	header;
@@ -323,6 +333,7 @@ enum perf_event_type { 
	 * struct {

	 *	struct perf_event_header	header;

	 *	u32				pid, ppid;

	 *	u32				tid, ptid;

	 * };

	 */

	PERF_EVENT_FORK			= 7,

init/Kconfig

+10 −1
Original line number Diff line number Diff line
@@ -940,6 +940,7 @@ menu "Performance Counters" 


config PERF_COUNTERS

	bool "Kernel Performance Counters"

	default y if PROFILING

	depends on HAVE_PERF_COUNTERS

	select ANON_INODES

	help
@@ -961,9 +962,17 @@ config PERF_COUNTERS 
	  Say Y if unsure.



config EVENT_PROFILE

	bool "Tracepoint profile sources"

	bool "Tracepoint profiling sources"

	depends on PERF_COUNTERS && EVENT_TRACING

	default y

	help

	 Allow the use of tracepoints as software performance counters.



	 When this is enabled, you can create perf counters based on

	 tracepoints using PERF_TYPE_TRACEPOINT and the tracepoint ID

	 found in debugfs://tracing/events/*/*/id. (The -e/--events

	 option to the perf tool can parse and interpret symbolic

	 tracepoints, in the subsystem:tracepoint_name format.)



endmenu

kernel/fork.c

+1 −3
Original line number Diff line number Diff line
@@ -1269,6 +1269,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, 
	write_unlock_irq(&tasklist_lock);

	proc_fork_connector(p);

	cgroup_post_fork(p);

	perf_counter_fork(p);

	return p;



bad_fork_free_pid:
@@ -1410,9 +1411,6 @@ long do_fork(unsigned long clone_flags, 
			init_completion(&vfork);

		}



		if (!(clone_flags & CLONE_THREAD))

			perf_counter_fork(p);



		audit_finish_fork(p);

		tracehook_report_clone(regs, clone_flags, nr, p);

kernel/perf_counter.c

+71 −30
Original line number Diff line number Diff line
@@ -42,6 +42,7 @@ static int perf_overcommit __read_mostly = 1; 
static atomic_t nr_counters __read_mostly;

static atomic_t nr_mmap_counters __read_mostly;

static atomic_t nr_comm_counters __read_mostly;

static atomic_t nr_task_counters __read_mostly;



/*

 * perf counter paranoia level:
@@ -1654,6 +1655,8 @@ static void free_counter(struct perf_counter *counter) 
			atomic_dec(&nr_mmap_counters);

		if (counter->attr.comm)

			atomic_dec(&nr_comm_counters);

		if (counter->attr.task)

			atomic_dec(&nr_task_counters);

	}



	if (counter->destroy)
@@ -1688,6 +1691,18 @@ static int perf_release(struct inode *inode, struct file *file) 
	return 0;

}



static u64 perf_counter_read_tree(struct perf_counter *counter)

{

	struct perf_counter *child;

	u64 total = 0;



	total += perf_counter_read(counter);

	list_for_each_entry(child, &counter->child_list, child_list)

		total += perf_counter_read(child);



	return total;

}



/*

 * Read the performance counter - simple non blocking version for now

 */
@@ -1707,7 +1722,7 @@ perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count) 


	WARN_ON_ONCE(counter->ctx->parent_ctx);

	mutex_lock(&counter->child_mutex);

	values[0] = perf_counter_read(counter);

	values[0] = perf_counter_read_tree(counter);

	n = 1;

	if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)

		values[n++] = counter->total_time_enabled +
@@ -2819,10 +2834,12 @@ perf_counter_read_event(struct perf_counter *counter, 
}



/*

 * fork tracking

 * task tracking -- fork/exit

 *

 * enabled by: attr.comm | attr.mmap | attr.task

 */



struct perf_fork_event {

struct perf_task_event {

	struct task_struct	*task;



	struct {
@@ -2830,37 +2847,42 @@ struct perf_fork_event { 


		u32				pid;

		u32				ppid;

		u32				tid;

		u32				ptid;

	} event;

};



static void perf_counter_fork_output(struct perf_counter *counter,

				     struct perf_fork_event *fork_event)

static void perf_counter_task_output(struct perf_counter *counter,

				     struct perf_task_event *task_event)

{

	struct perf_output_handle handle;

	int size = fork_event->event.header.size;

	struct task_struct *task = fork_event->task;

	int size = task_event->event.header.size;

	struct task_struct *task = task_event->task;

	int ret = perf_output_begin(&handle, counter, size, 0, 0);



	if (ret)

		return;



	fork_event->event.pid = perf_counter_pid(counter, task);

	fork_event->event.ppid = perf_counter_pid(counter, task->real_parent);

	task_event->event.pid = perf_counter_pid(counter, task);

	task_event->event.ppid = perf_counter_pid(counter, task->real_parent);



	perf_output_put(&handle, fork_event->event);

	task_event->event.tid = perf_counter_tid(counter, task);

	task_event->event.ptid = perf_counter_tid(counter, task->real_parent);



	perf_output_put(&handle, task_event->event);

	perf_output_end(&handle);

}



static int perf_counter_fork_match(struct perf_counter *counter)

static int perf_counter_task_match(struct perf_counter *counter)

{

	if (counter->attr.comm || counter->attr.mmap)

	if (counter->attr.comm || counter->attr.mmap || counter->attr.task)

		return 1;



	return 0;

}



static void perf_counter_fork_ctx(struct perf_counter_context *ctx,

				  struct perf_fork_event *fork_event)

static void perf_counter_task_ctx(struct perf_counter_context *ctx,

				  struct perf_task_event *task_event)

{

	struct perf_counter *counter;
@@ -2869,19 +2891,19 @@ static void perf_counter_fork_ctx(struct perf_counter_context *ctx, 


	rcu_read_lock();

	list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) {

		if (perf_counter_fork_match(counter))

			perf_counter_fork_output(counter, fork_event);

		if (perf_counter_task_match(counter))

			perf_counter_task_output(counter, task_event);

	}

	rcu_read_unlock();

}



static void perf_counter_fork_event(struct perf_fork_event *fork_event)

static void perf_counter_task_event(struct perf_task_event *task_event)

{

	struct perf_cpu_context *cpuctx;

	struct perf_counter_context *ctx;



	cpuctx = &get_cpu_var(perf_cpu_context);

	perf_counter_fork_ctx(&cpuctx->ctx, fork_event);

	perf_counter_task_ctx(&cpuctx->ctx, task_event);

	put_cpu_var(perf_cpu_context);



	rcu_read_lock();
@@ -2891,32 +2913,40 @@ static void perf_counter_fork_event(struct perf_fork_event *fork_event) 
	 */

	ctx = rcu_dereference(current->perf_counter_ctxp);

	if (ctx)

		perf_counter_fork_ctx(ctx, fork_event);

		perf_counter_task_ctx(ctx, task_event);

	rcu_read_unlock();

}



void perf_counter_fork(struct task_struct *task)

static void perf_counter_task(struct task_struct *task, int new)

{

	struct perf_fork_event fork_event;

	struct perf_task_event task_event;



	if (!atomic_read(&nr_comm_counters) &&

	    !atomic_read(&nr_mmap_counters))

	    !atomic_read(&nr_mmap_counters) &&

	    !atomic_read(&nr_task_counters))

		return;



	fork_event = (struct perf_fork_event){

	task_event = (struct perf_task_event){

		.task	= task,

		.event  = {

			.header = {

				.type = PERF_EVENT_FORK,

				.type = new ? PERF_EVENT_FORK : PERF_EVENT_EXIT,

				.misc = 0,

				.size = sizeof(fork_event.event),

				.size = sizeof(task_event.event),

			},

			/* .pid  */

			/* .ppid */

			/* .tid  */

			/* .ptid */

		},

	};



	perf_counter_fork_event(&fork_event);

	perf_counter_task_event(&task_event);

}



void perf_counter_fork(struct task_struct *task)

{

	perf_counter_task(task, 1);

}



/*
@@ -3875,6 +3905,8 @@ done: 
			atomic_inc(&nr_mmap_counters);

		if (counter->attr.comm)

			atomic_inc(&nr_comm_counters);

		if (counter->attr.task)

			atomic_inc(&nr_task_counters);

	}



	return counter;
@@ -4236,8 +4268,10 @@ void perf_counter_exit_task(struct task_struct *child) 
	struct perf_counter_context *child_ctx;

	unsigned long flags;



	if (likely(!child->perf_counter_ctxp))

	if (likely(!child->perf_counter_ctxp)) {

		perf_counter_task(child, 0);

		return;

	}



	local_irq_save(flags);

	/*
@@ -4255,15 +4289,22 @@ void perf_counter_exit_task(struct task_struct *child) 
	 * incremented the context's refcount before we do put_ctx below.

	 */

	spin_lock(&child_ctx->lock);

	child->perf_counter_ctxp = NULL;

	/*

	 * If this context is a clone; unclone it so it can't get

	 * swapped to another process while we're removing all

	 * the counters from it.

	 */

	unclone_ctx(child_ctx);

	spin_unlock(&child_ctx->lock);

	local_irq_restore(flags);

	spin_unlock_irqrestore(&child_ctx->lock, flags);



	/*

	 * Report the task dead after unscheduling the counters so that we

	 * won't get any samples after PERF_EVENT_EXIT. We can however still

	 * get a few PERF_EVENT_READ events.

	 */

	perf_counter_task(child, 0);



	child->perf_counter_ctxp = NULL;



	/*

	 * We can recurse on the same lock type through:

tools/perf/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -345,7 +345,7 @@ BUILTIN_OBJS += builtin-stat.o 
BUILTIN_OBJS += builtin-top.o



PERFLIBS = $(LIB_FILE)

EXTLIBS = -lbfd

EXTLIBS = -lbfd -liberty



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