Commit 3af9e859 authored by Eric B Munson's avatar Eric B Munson Committed by Ingo Molnar
Browse files

perf: Add non-exec mmap() tracking 



Add the capacility to track data mmap()s. This can be used together
with PERF_SAMPLE_ADDR for data profiling.

Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
[Updated code for stable perf ABI]
Signed-off-by: default avatarEric B Munson <ebmunson@us.ibm.com>
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1274193049-25997-1-git-send-email-ebmunson@us.ibm.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 8ed92280

fs/exec.c

+1 −0
Original line number Diff line number Diff line
@@ -653,6 +653,7 @@ int setup_arg_pages(struct linux_binprm *bprm, 
	else

		stack_base = vma->vm_start - stack_expand;

#endif

	current->mm->start_stack = bprm->p;

	ret = expand_stack(vma, stack_base);

	if (ret)

		ret = -EFAULT;

include/linux/perf_event.h

+3 −9
Original line number Diff line number Diff line
@@ -214,8 +214,9 @@ struct perf_event_attr { 
				 *  See also PERF_RECORD_MISC_EXACT_IP

				 */

				precise_ip     :  2, /* skid constraint       */

				mmap_data      :  1, /* non-exec mmap data    */



				__reserved_1   : 47;

				__reserved_1   : 46;



	union {

		__u32		wakeup_events;	  /* wakeup every n events */
@@ -962,14 +963,7 @@ perf_sw_event(u32 event_id, u64 nr, int nmi, struct pt_regs *regs, u64 addr) 
	}

}



extern void __perf_event_mmap(struct vm_area_struct *vma);



static inline void perf_event_mmap(struct vm_area_struct *vma)

{

	if (vma->vm_flags & VM_EXEC)

		__perf_event_mmap(vma);

}



extern void perf_event_mmap(struct vm_area_struct *vma);

extern struct perf_guest_info_callbacks *perf_guest_cbs;

extern int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);

extern int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);

kernel/perf_event.c

+23 −11
Original line number Diff line number Diff line
@@ -1891,7 +1891,7 @@ static void free_event(struct perf_event *event) 


	if (!event->parent) {

		atomic_dec(&nr_events);

		if (event->attr.mmap)

		if (event->attr.mmap || event->attr.mmap_data)

			atomic_dec(&nr_mmap_events);

		if (event->attr.comm)

			atomic_dec(&nr_comm_events);
@@ -3491,7 +3491,7 @@ perf_event_read_event(struct perf_event *event, 
/*

 * task tracking -- fork/exit

 *

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

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

 */



struct perf_task_event {
@@ -3541,7 +3541,8 @@ static int perf_event_task_match(struct perf_event *event) 
	if (event->cpu != -1 && event->cpu != smp_processor_id())

		return 0;



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

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

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

		return 1;



	return 0;
@@ -3766,7 +3767,8 @@ static void perf_event_mmap_output(struct perf_event *event, 
}



static int perf_event_mmap_match(struct perf_event *event,

				   struct perf_mmap_event *mmap_event)

				   struct perf_mmap_event *mmap_event,

				   int executable)

{

	if (event->state < PERF_EVENT_STATE_INACTIVE)

		return 0;
@@ -3774,19 +3776,21 @@ static int perf_event_mmap_match(struct perf_event *event, 
	if (event->cpu != -1 && event->cpu != smp_processor_id())

		return 0;



	if (event->attr.mmap)

	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)

				  struct perf_mmap_event *mmap_event,

				  int executable)

{

	struct perf_event *event;



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

		if (perf_event_mmap_match(event, mmap_event))

		if (perf_event_mmap_match(event, mmap_event, executable))

			perf_event_mmap_output(event, mmap_event);

	}

}
@@ -3830,6 +3834,14 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) 
		if (!vma->vm_mm) {

			name = strncpy(tmp, "[vdso]", sizeof(tmp));

			goto got_name;

		} else if (vma->vm_start <= vma->vm_mm->start_brk &&

				vma->vm_end >= vma->vm_mm->brk) {

			name = strncpy(tmp, "[heap]", sizeof(tmp));

			goto got_name;

		} else if (vma->vm_start <= vma->vm_mm->start_stack &&

				vma->vm_end >= vma->vm_mm->start_stack) {

			name = strncpy(tmp, "[stack]", sizeof(tmp));

			goto got_name;

		}



		name = strncpy(tmp, "//anon", sizeof(tmp));
@@ -3846,17 +3858,17 @@ got_name: 


	rcu_read_lock();

	cpuctx = &get_cpu_var(perf_cpu_context);

	perf_event_mmap_ctx(&cpuctx->ctx, mmap_event);

	perf_event_mmap_ctx(&cpuctx->ctx, mmap_event, vma->vm_flags & VM_EXEC);

	ctx = rcu_dereference(current->perf_event_ctxp);

	if (ctx)

		perf_event_mmap_ctx(ctx, mmap_event);

		perf_event_mmap_ctx(ctx, mmap_event, vma->vm_flags & VM_EXEC);

	put_cpu_var(perf_cpu_context);

	rcu_read_unlock();



	kfree(buf);

}



void __perf_event_mmap(struct vm_area_struct *vma)

void perf_event_mmap(struct vm_area_struct *vma)

{

	struct perf_mmap_event mmap_event;
@@ -4911,7 +4923,7 @@ done: 


	if (!event->parent) {

		atomic_inc(&nr_events);

		if (event->attr.mmap)

		if (event->attr.mmap || event->attr.mmap_data)

			atomic_inc(&nr_mmap_events);

		if (event->attr.comm)

			atomic_inc(&nr_comm_events);

mm/mmap.c

+5 −1
Original line number Diff line number Diff line
@@ -1734,8 +1734,10 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address) 
		grow = (address - vma->vm_end) >> PAGE_SHIFT;



		error = acct_stack_growth(vma, size, grow);

		if (!error)

		if (!error) {

			vma->vm_end = address;

			perf_event_mmap(vma);

		}

	}

	anon_vma_unlock(vma);

	return error;
@@ -1781,6 +1783,7 @@ static int expand_downwards(struct vm_area_struct *vma, 
		if (!error) {

			vma->vm_start = address;

			vma->vm_pgoff -= grow;

			perf_event_mmap(vma);

		}

	}

	anon_vma_unlock(vma);
@@ -2208,6 +2211,7 @@ unsigned long do_brk(unsigned long addr, unsigned long len) 
	vma->vm_page_prot = vm_get_page_prot(flags);

	vma_link(mm, vma, prev, rb_link, rb_parent);

out:

	perf_event_mmap(vma);

	mm->total_vm += len >> PAGE_SHIFT;

	if (flags & VM_LOCKED) {

		if (!mlock_vma_pages_range(vma, addr, addr + len))

tools/perf/builtin-record.c

+3 −1
Original line number Diff line number Diff line
@@ -268,8 +268,10 @@ static void create_counter(int counter, int cpu) 
	if (inherit_stat)

		attr->inherit_stat = 1;



	if (sample_address)

	if (sample_address) {

		attr->sample_type	|= PERF_SAMPLE_ADDR;

		attr->mmap_data = track;

	}



	if (call_graph)

		attr->sample_type	|= PERF_SAMPLE_CALLCHAIN;

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