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: Anton Blanchard <anton@samba.org>
[Updated code for stable perf ABI]
Signed-off-by: Eric B Munson <ebmunson@us.ibm.com>
Signed-off-by: Peter 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: Ingo Molnar <mingo@elte.hu>

diff --git a/fs/exec.c b/fs/exec.c
index e19de6a80339b3ceeae267283962f271ac6c5e55..97d91a03fb1339c03f2b78c42a0010d0266b1fbd 100644 (file)
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -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;

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index c691a0b27bcd51b588f47a3e6704a0188b1aa657..36efad90cd43132773eeb089bd308284954fb11d 100644 (file)
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -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);

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index b39bec346e806e3ba4e003d69c5b46449d32e432..227ed9c8ec34442e7a4e0de7ec40e5e584e5ba39 100644 (file)
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -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);

diff --git a/mm/mmap.c b/mm/mmap.c
index 456ec6f278897a560bd915e6d84297ac3de7ddef..e38e910cb75673c528116e9e0a114fb0c8f3b8cb 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -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))

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 5e5c6403a3158b01854649a924d23841466e71c9..39c7247bc54aa707b5fa4bef05b5e2bae0127d01 100644 (file)
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -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;