On 6/22/23 16:48, Christian König wrote:
Am 22.06.23 um 16:08 schrieb Thomas Hellström:
On 6/22/23 15:55, Andi Shyti wrote:
Hi Thomas,
On Thu, Jun 22, 2023 at 12:14:11PM +0200, Thomas Hellström wrote:
On eviction errors other than -EMULTIHOP we were leaking a resource.
Fix.
Fixes: 403797925768 ("drm/ttm: Fix multihop assert on eviction.")
Cc: Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx>
Cc: Christian König <christian.koenig@xxxxxxx>
Cc: Christian Koenig <christian.koenig@xxxxxxx>
Cc: Huang Rui <ray.huang@xxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: <stable@xxxxxxxxxxxxxxx> # v5.15+
Signed-off-by: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/ttm/ttm_bo.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c
b/drivers/gpu/drm/ttm/ttm_bo.c
index 615d30c4262d..89530f2a027f 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -462,14 +462,14 @@ static int ttm_bo_evict(struct
ttm_buffer_object *bo,
ret = ttm_bo_handle_move_mem(bo, evict_mem, true, ctx, &hop);
if (ret == -EMULTIHOP) {
ret = ttm_bo_bounce_temp_buffer(bo, &evict_mem, ctx, &hop);
- if (ret) {
- if (ret != -ERESTARTSYS && ret != -EINTR)
- pr_err("Buffer eviction failed\n");
- ttm_resource_free(bo, &evict_mem);
- goto out;
- }
- /* try and move to final place now. */
- goto bounce;
+ if (!ret)
+ /* try and move to final place now. */
+ goto bounce;
As we are at this, can't we replace this with a while()? Goto's
used instead of a while loop are a fist in the eye...
I'm completely OK with that. this patch already did away with one of
them. Let's hear Christian's opinion first, though.
I'm not a fan of that goto either, but could we somehow avoid the
while(1) ? E.g. something like do { } while (!ret) after handling the
multihop?
I think the construct that makes it most obvious what's happening,
although it needs two tests for -EMULTIHOP is something like
do {
....
if (ret != -EMULTIHOP)
break;
....
} while (ret ==-EMULTIHOP);
Will be out tomorrow, though, so I don't have time to respin before Monday.
/Thomas
Christian.
Thanks,
Thomas
It looks even better:
while (1) {
ret = ttm_bo_handle_move_mem(bo, evict_mem, true, ctx, &hop);
if (!ret)
break;
if (ret == -EMULTIHOP)
ret = ttm_bo_bounce_temp_buffer(bo, &evict_mem,
ctx, &hop);
/* try again */
if (!ret)
continue;
ttm_resource_free(bo, &evict_mem);
if (ret != -ERESTARTSYS && ret != -EINTR)
pr_err("Buffer eviction failed\n");
break;
}
Andi
+ }
+ if (ret) {
+ ttm_resource_free(bo, &evict_mem);
+ if (ret != -ERESTARTSYS && ret != -EINTR)
+ pr_err("Buffer eviction failed\n");
}
out:
return ret;
--
2.40.1
