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@amd.com Cc: Christian König christian.koenig@amd.com Cc: Christian Koenig christian.koenig@amd.com Cc: Huang Rui ray.huang@amd.com Cc: dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org # v5.15+ Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com
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