Commit 52d857a8 authored by Jiri Olsa's avatar Jiri Olsa Committed by Ingo Molnar
Browse files

perf: Factor out auxiliary events notification 



Add perf_event_aux() function to send out all types of
auxiliary events - mmap, task, comm events. For each type
there's match and output functions defined and used as
callbacks during perf_event_aux processing.

This way we can centralize the pmu/context iterating and
event matching logic. Also since lot of the code was
duplicated, this patch reduces the .text size about 2kB
on my setup:

  snipped output from 'objdump -x kernel/events/core.o'

  before:
  Idx Name          Size
    0 .text         0000d313

  after:
  Idx Name          Size
    0 .text         0000cad3

Signed-off-by: default avatarJiri Olsa <jolsa@redhat.com>
Acked-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/1367857638-27631-3-git-send-email-jolsa@redhat.com


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 524eff18

kernel/events/core.c

+89 −153
Original line number Diff line number Diff line
@@ -4394,6 +4394,64 @@ perf_event_read_event(struct perf_event *event, 
	perf_output_end(&handle);

}



typedef int  (perf_event_aux_match_cb)(struct perf_event *event, void *data);

typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data);



static void

perf_event_aux_ctx(struct perf_event_context *ctx,

		   perf_event_aux_match_cb match,

		   perf_event_aux_output_cb output,

		   void *data)

{

	struct perf_event *event;



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

		if (event->state < PERF_EVENT_STATE_INACTIVE)

			continue;

		if (!event_filter_match(event))

			continue;

		if (match(event, data))

			output(event, data);

	}

}



static void

perf_event_aux(perf_event_aux_match_cb match,

	       perf_event_aux_output_cb output,

	       void *data,

	       struct perf_event_context *task_ctx)

{

	struct perf_cpu_context *cpuctx;

	struct perf_event_context *ctx;

	struct pmu *pmu;

	int ctxn;



	rcu_read_lock();

	list_for_each_entry_rcu(pmu, &pmus, entry) {

		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);

		if (cpuctx->unique_pmu != pmu)

			goto next;

		perf_event_aux_ctx(&cpuctx->ctx, match, output, data);

		if (task_ctx)

			goto next;

		ctxn = pmu->task_ctx_nr;

		if (ctxn < 0)

			goto next;

		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);

		if (ctx)

			perf_event_aux_ctx(ctx, match, output, data);

next:

		put_cpu_ptr(pmu->pmu_cpu_context);

	}



	if (task_ctx) {

		preempt_disable();

		perf_event_aux_ctx(task_ctx, match, output, data);

		preempt_enable();

	}

	rcu_read_unlock();

}



/*

 * task tracking -- fork/exit

 *
@@ -4416,8 +4474,9 @@ struct perf_task_event { 
};



static void perf_event_task_output(struct perf_event *event,

				     struct perf_task_event *task_event)

				   void *data)

{

	struct perf_task_event *task_event = data;

	struct perf_output_handle handle;

	struct perf_sample_data	sample;

	struct task_struct *task = task_event->task;
@@ -4445,64 +4504,11 @@ out: 
	task_event->event_id.header.size = size;

}



static int perf_event_task_match(struct perf_event *event)

{

	if (event->state < PERF_EVENT_STATE_INACTIVE)

		return 0;



	if (!event_filter_match(event))

		return 0;



	if (event->attr.comm || event->attr.mmap ||

	    event->attr.mmap_data || event->attr.task)

		return 1;



	return 0;

}



static void perf_event_task_ctx(struct perf_event_context *ctx,

				  struct perf_task_event *task_event)

static int perf_event_task_match(struct perf_event *event,

				 void *data __maybe_unused)

{

	struct perf_event *event;



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

		if (perf_event_task_match(event))

			perf_event_task_output(event, task_event);

	}

}



static void perf_event_task_event(struct perf_task_event *task_event)

{

	struct perf_cpu_context *cpuctx;

	struct perf_event_context *ctx, *task_ctx = task_event->task_ctx;

	struct pmu *pmu;

	int ctxn;



	rcu_read_lock();

	list_for_each_entry_rcu(pmu, &pmus, entry) {

		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);

		if (cpuctx->unique_pmu != pmu)

			goto next;

		perf_event_task_ctx(&cpuctx->ctx, task_event);



		if (task_ctx)

			goto next;

		ctxn = pmu->task_ctx_nr;

		if (ctxn < 0)

			goto next;

		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);

		if (ctx)

			perf_event_task_ctx(ctx, task_event);

next:

		put_cpu_ptr(pmu->pmu_cpu_context);

	}

	if (task_ctx) {

		preempt_disable();

		perf_event_task_ctx(task_ctx, task_event);

		preempt_enable();

	}



	rcu_read_unlock();

	return event->attr.comm || event->attr.mmap ||

	       event->attr.mmap_data || event->attr.task;

}



static void perf_event_task(struct task_struct *task,
@@ -4533,7 +4539,10 @@ static void perf_event_task(struct task_struct *task, 
		},

	};



	perf_event_task_event(&task_event);

	perf_event_aux(perf_event_task_match,

		       perf_event_task_output,

		       &task_event,

		       task_ctx);

}



void perf_event_fork(struct task_struct *task)
@@ -4559,8 +4568,9 @@ struct perf_comm_event { 
};



static void perf_event_comm_output(struct perf_event *event,

				     struct perf_comm_event *comm_event)

				   void *data)

{

	struct perf_comm_event *comm_event = data;

	struct perf_output_handle handle;

	struct perf_sample_data sample;

	int size = comm_event->event_id.header.size;
@@ -4587,39 +4597,16 @@ out: 
	comm_event->event_id.header.size = size;

}



static int perf_event_comm_match(struct perf_event *event)

{

	if (event->state < PERF_EVENT_STATE_INACTIVE)

		return 0;



	if (!event_filter_match(event))

		return 0;



	if (event->attr.comm)

		return 1;



	return 0;

}



static void perf_event_comm_ctx(struct perf_event_context *ctx,

				  struct perf_comm_event *comm_event)

static int perf_event_comm_match(struct perf_event *event,

				 void *data __maybe_unused)

{

	struct perf_event *event;



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

		if (perf_event_comm_match(event))

			perf_event_comm_output(event, comm_event);

	}

	return event->attr.comm;

}



static void perf_event_comm_event(struct perf_comm_event *comm_event)

{

	struct perf_cpu_context *cpuctx;

	struct perf_event_context *ctx;

	char comm[TASK_COMM_LEN];

	unsigned int size;

	struct pmu *pmu;

	int ctxn;



	memset(comm, 0, sizeof(comm));

	strlcpy(comm, comm_event->task->comm, sizeof(comm));
@@ -4629,24 +4616,11 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event) 
	comm_event->comm_size = size;



	comm_event->event_id.header.size = sizeof(comm_event->event_id) + size;

	rcu_read_lock();

	list_for_each_entry_rcu(pmu, &pmus, entry) {

		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);

		if (cpuctx->unique_pmu != pmu)

			goto next;

		perf_event_comm_ctx(&cpuctx->ctx, comm_event);



		ctxn = pmu->task_ctx_nr;

		if (ctxn < 0)

			goto next;



		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);

		if (ctx)

			perf_event_comm_ctx(ctx, comm_event);

next:

		put_cpu_ptr(pmu->pmu_cpu_context);

	}

	rcu_read_unlock();

	perf_event_aux(perf_event_comm_match,

		       perf_event_comm_output,

		       comm_event,

		       NULL);

}



void perf_event_comm(struct task_struct *task)
@@ -4708,8 +4682,9 @@ struct perf_mmap_event { 
};



static void perf_event_mmap_output(struct perf_event *event,

				     struct perf_mmap_event *mmap_event)

				   void *data)

{

	struct perf_mmap_event *mmap_event = data;

	struct perf_output_handle handle;

	struct perf_sample_data sample;

	int size = mmap_event->event_id.header.size;
@@ -4736,46 +4711,24 @@ out: 
}



static int perf_event_mmap_match(struct perf_event *event,

				   struct perf_mmap_event *mmap_event,

				   int executable)

{

	if (event->state < PERF_EVENT_STATE_INACTIVE)

		return 0;



	if (!event_filter_match(event))

		return 0;



	if ((!executable && event->attr.mmap_data) ||

	    (executable && event->attr.mmap))

		return 1;



	return 0;

}



static void perf_event_mmap_ctx(struct perf_event_context *ctx,

				  struct perf_mmap_event *mmap_event,

				  int executable)

				 void *data)

{

	struct perf_event *event;

	struct perf_mmap_event *mmap_event = data;

	struct vm_area_struct *vma = mmap_event->vma;

	int executable = vma->vm_flags & VM_EXEC;



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

		if (perf_event_mmap_match(event, mmap_event, executable))

			perf_event_mmap_output(event, mmap_event);

	}

	return (!executable && event->attr.mmap_data) ||

	       (executable && event->attr.mmap);

}



static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)

{

	struct perf_cpu_context *cpuctx;

	struct perf_event_context *ctx;

	struct vm_area_struct *vma = mmap_event->vma;

	struct file *file = vma->vm_file;

	unsigned int size;

	char tmp[16];

	char *buf = NULL;

	const char *name;

	struct pmu *pmu;

	int ctxn;



	memset(tmp, 0, sizeof(tmp));
@@ -4831,27 +4784,10 @@ got_name: 


	mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;



	rcu_read_lock();

	list_for_each_entry_rcu(pmu, &pmus, entry) {

		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);

		if (cpuctx->unique_pmu != pmu)

			goto next;

		perf_event_mmap_ctx(&cpuctx->ctx, mmap_event,

					vma->vm_flags & VM_EXEC);



		ctxn = pmu->task_ctx_nr;

		if (ctxn < 0)

			goto next;



		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);

		if (ctx) {

			perf_event_mmap_ctx(ctx, mmap_event,

					vma->vm_flags & VM_EXEC);

		}

next:

		put_cpu_ptr(pmu->pmu_cpu_context);

	}

	rcu_read_unlock();

	perf_event_aux(perf_event_mmap_match,

		       perf_event_mmap_output,

		       mmap_event,

		       NULL);



	kfree(buf);

}

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