From: Michal Hocko <mhocko@xxxxxxxx>
Subject: drm/amdgpu: make amdgpu_mn_get wait for mmap_sem killable
amdgpu_mn_get which is called during ioct path relies on mmap_sem for
write. If the waiting task gets killed by the oom killer it would block
oom_reaper from asynchronous address space reclaim and reduce the chances
of timely OOM resolving. Wait for the lock in the killable mode and
return with EINTR if the task got killed while waiting.
[arnd@xxxxxxxx: use ERR_PTR() to return from amdgpu_mn_get]
Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Reviewed-by: Christian König <christian.koenig@xxxxxxx>
Cc: David Airlie <airlied@xxxxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff -puN drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c~drm-amdgpu-make-amdgpu_mn_get-wait-for-mmap_sem-killable drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c~drm-amdgpu-make-amdgpu_mn_get-wait-for-mmap_sem-killable
+++ a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
@@ -232,7 +232,10 @@ static struct amdgpu_mn *amdgpu_mn_get(s
int r;
mutex_lock(&adev->mn_lock);
- down_write(&mm->mmap_sem);
+ if (down_write_killable(&mm->mmap_sem)) {
+ mutex_unlock(&adev->mn_lock);
+ return ERR_PTR(-EINTR);
+ }
hash_for_each_possible(adev->mn_hash, rmn, node, (unsigned long)mm)
if (rmn->mm == mm)
_
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
