[tip:perfcounters/core] perf_counter: Generate mmap events for install_special_mapping()

tip-bot for Peter Zijlstra
2009-06-05T13:22:39Z

Commit-ID: 089dd79db9264dc0da602bad45d42f1b3e7d1e07
Gitweb: http://git.kernel.org/tip/089dd79db9264dc0da602bad45d42f1b3e7d1e07
Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
AuthorDate: Fri, 5 Jun 2009 14:04:55 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Fri, 5 Jun 2009 14:46:41 +0200

perf_counter: Generate mmap events for install_special_mapping()

In order to track the vdso also generate mmap events for
install_special_mapping().

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
include/linux/perf_counter.h | 14 ++++++++------
kernel/perf_counter.c | 34 ++++++++++++++++++++++------------
mm/mmap.c | 5 +++--
3 files changed, 33 insertions(+), 20 deletions(-)

diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index 6ca403a..40dc0e2 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -617,8 +617,13 @@ static inline int is_software_counter(struct perf_counter *counter)

extern void perf_swcounter_event(u32, u64, int, struct pt_regs *, u64);

-extern void perf_counter_mmap(unsigned long addr, unsigned long len,
- unsigned long pgoff, struct file *file);
+extern void __perf_counter_mmap(struct vm_area_struct *vma);
+
+static inline void perf_counter_mmap(struct vm_area_struct *vma)
+{
+ if (vma->vm_flags & VM_EXEC)
+ __perf_counter_mmap(vma);
+}

extern void perf_counter_comm(struct task_struct *tsk);
extern void perf_counter_fork(struct task_struct *tsk);
@@ -668,10 +673,7 @@ static inline void
perf_swcounter_event(u32 event, u64 nr, int nmi,
struct pt_regs *regs, u64 addr) { }

-static inline void
-perf_counter_mmap(unsigned long addr, unsigned long len,
- unsigned long pgoff, struct file *file) { }
-
+static inline void perf_counter_mmap(struct vm_area_struct *vma) { }
static inline void perf_counter_comm(struct task_struct *tsk) { }
static inline void perf_counter_fork(struct task_struct *tsk) { }
static inline void perf_counter_init(void) { }
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index a5d3e2a..37a5a24 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -2255,7 +2255,7 @@ out:
}

static void perf_output_copy(struct perf_output_handle *handle,
- void *buf, unsigned int len)
+ const void *buf, unsigned int len)
{
unsigned int pages_mask;
unsigned int offset;
@@ -2681,9 +2681,10 @@ void perf_counter_comm(struct task_struct *task)
*/

struct perf_mmap_event {
- struct file *file;
- char *file_name;
- int file_size;
+ struct vm_area_struct *vma;
+
+ const char *file_name;
+ int file_size;

struct {
struct perf_event_header header;
@@ -2744,11 +2745,12 @@ static void perf_counter_mmap_event(struct perf_mmap_event *mmap_event)
{
struct perf_cpu_context *cpuctx;
struct perf_counter_context *ctx;
- struct file *file = mmap_event->file;
+ struct vm_area_struct *vma = mmap_event->vma;
+ struct file *file = vma->vm_file;
unsigned int size;
char tmp[16];
char *buf = NULL;
- char *name;
+ const char *name;

if (file) {
buf = kzalloc(PATH_MAX, GFP_KERNEL);
@@ -2762,6 +2764,15 @@ static void perf_counter_mmap_event(struct perf_mmap_event *mmap_event)
goto got_name;
}
} else {
+ name = arch_vma_name(mmap_event->vma);
+ if (name)
+ goto got_name;
+
+ if (!vma->vm_mm) {
+ name = strncpy(tmp, "[vdso]", sizeof(tmp));
+ goto got_name;
+ }
+
name = strncpy(tmp, "//anon", sizeof(tmp));
goto got_name;
}
@@ -2791,8 +2802,7 @@ got_name:
kfree(buf);
}

-void perf_counter_mmap(unsigned long addr, unsigned long len,
- unsigned long pgoff, struct file *file)
+void __perf_counter_mmap(struct vm_area_struct *vma)
{
struct perf_mmap_event mmap_event;

@@ -2800,12 +2810,12 @@ void perf_counter_mmap(unsigned long addr, unsigned long len,
return;

mmap_event = (struct perf_mmap_event){
- .file = file,
+ .vma = vma,
.event = {
.header = { .type = PERF_EVENT_MMAP, },
- .start = addr,
- .len = len,
- .pgoff = pgoff,
+ .start = vma->vm_start,
+ .len = vma->vm_end - vma->vm_start,
+ .pgoff = vma->vm_pgoff,
},
};

diff --git a/mm/mmap.c b/mm/mmap.c
index 6451ce2..8101de4 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1220,8 +1220,7 @@ munmap_back:
if (correct_wcount)
atomic_inc(&inode->i_writecount);
out:
- if (vm_flags & VM_EXEC)
- perf_counter_mmap(addr, len, pgoff, file);
+ perf_counter_mmap(vma);

mm->total_vm += len >> PAGE_SHIFT;
vm_stat_account(mm, vm_flags, file, len >> PAGE_SHIFT);
@@ -2309,6 +2308,8 @@ int install_special_mapping(struct mm_struct *mm,

mm->total_vm += len >> PAGE_SHIFT;

+ perf_counter_mmap(vma);
+
return 0;
}