In the future mm->exe_file will be done without mmap_sem
serialization, thus isolate and reorganize the related
code to make the transition easier. Good users will, make
use of the more standard get_mm_exe_file(), requiring only
holding the mmap_sem to read the value, and relying on reference
counting to make sure that the exe file won't dissappear
underneath us while getting the dcookie.
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Robert Richter <rric@xxxxxxxxxx>
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: cbe-oss-dev@xxxxxxxxxxxxxxxx
Cc: oprofile-list@xxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
---
Completely untested.
arch/powerpc/oprofile/cell/spu_task_sync.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/oprofile/cell/spu_task_sync.c b/arch/powerpc/oprofile/cell/spu_task_sync.c
index 1c27831..ed7b097 100644
--- a/arch/powerpc/oprofile/cell/spu_task_sync.c
+++ b/arch/powerpc/oprofile/cell/spu_task_sync.c
@@ -22,6 +22,7 @@
#include <linux/kref.h>
#include <linux/mm.h>
#include <linux/fs.h>
+#include <linux/file.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/numa.h>
@@ -322,18 +323,20 @@ get_exec_dcookie_and_offset(struct spu *spu, unsigned int *offsetp,
unsigned long app_cookie = 0;
unsigned int my_offset = 0;
struct vm_area_struct *vma;
+ struct file *exe_file;
struct mm_struct *mm = spu->mm;
if (!mm)
goto out;
- down_read(&mm->mmap_sem);
-
- if (mm->exe_file) {
- app_cookie = fast_get_dcookie(&mm->exe_file->f_path);
- pr_debug("got dcookie for %pD\n", mm->exe_file);
+ exe_file = get_mm_exe_file(mm);
+ if (exe_file) {
+ app_cookie = fast_get_dcookie(&exe_file->f_path);
+ pr_debug("got dcookie for %pD\n", exe_file);
+ fput(exe_file);
}
+ down_read(&mm->mmap_sem);
for (vma = mm->mmap; vma; vma = vma->vm_next) {
if (vma->vm_start > spu_ref || vma->vm_end <= spu_ref)
continue;
--
2.1.4
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