| Message ID | 1572361484-9828-1-git-send-email-andrey.grodzovsky@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/sched: Fix passing zero to 'PTR_ERR' warning | expand |
Am 29.10.19 um 16:04 schrieb Andrey Grodzovsky: > Fix a static code checker warning. > > Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com> Well that one was even new to me. Patch is Reviewed-by: Christian König <christian.koenig@amd.com> > --- > drivers/gpu/drm/scheduler/sched_main.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c > index f39b97e..898b0c9 100644 > --- a/drivers/gpu/drm/scheduler/sched_main.c > +++ b/drivers/gpu/drm/scheduler/sched_main.c > @@ -497,7 +497,7 @@ void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched) > > if (IS_ERR_OR_NULL(fence)) { > s_job->s_fence->parent = NULL; > - dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); > + dma_fence_set_error(&s_fence->finished, PTR_ERR_OR_ZERO(fence)); > } else { > s_job->s_fence->parent = fence; > } > @@ -742,7 +742,7 @@ static int drm_sched_main(void *param) > dma_fence_put(fence); > } else { > > - dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); > + dma_fence_set_error(&s_fence->finished, PTR_ERR_OR_ZERO(fence)); > drm_sched_process_job(NULL, &sched_job->cb); > } >
On Tue, Oct 29, 2019 at 11:04:44AM -0400, Andrey Grodzovsky wrote: > Fix a static code checker warning. > > Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com> > --- > drivers/gpu/drm/scheduler/sched_main.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c > index f39b97e..898b0c9 100644 > --- a/drivers/gpu/drm/scheduler/sched_main.c > +++ b/drivers/gpu/drm/scheduler/sched_main.c > @@ -497,7 +497,7 @@ void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched) > > if (IS_ERR_OR_NULL(fence)) { > s_job->s_fence->parent = NULL; > - dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); > + dma_fence_set_error(&s_fence->finished, PTR_ERR_OR_ZERO(fence)); This will silence the static checker warning, but it will still trigger a WARN_ON(). And it sort of has inspired me to generate a new warning because that's not how PTR_ERR_OR_ZERO() is supposed to be used. :P PTR_ERR_OR_ZERO() is short hand for this situation: - if (IS_ERR(fence)) - return PTR_ERR(fence); - return 0; + return PTR_ERR_OR_ZERO(fence); regards, dan carpenter
On Tue, Oct 29, 2019 at 11:04:44AM -0400, Andrey Grodzovsky wrote: > Fix a static code checker warning. > > Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com> > --- > drivers/gpu/drm/scheduler/sched_main.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c > index f39b97e..898b0c9 100644 > --- a/drivers/gpu/drm/scheduler/sched_main.c > +++ b/drivers/gpu/drm/scheduler/sched_main.c > @@ -497,7 +497,7 @@ void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched) > fence = sched->ops->run_job(s_job); > > if (IS_ERR_OR_NULL(fence)) { > s_job->s_fence->parent = NULL; > - dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); > + dma_fence_set_error(&s_fence->finished, PTR_ERR_OR_ZERO(fence)); I feel like I should explain better. It's generally bad to mix NULL and error pointers. The situation where you would do it is when NULL is a special case of success. A typical situation is you request a feature, like maybe logging for example: p = get_logger(); If there isn't enough memory then get_logger() returns ERR_PTR(-ENOMEM); but if the user has disabled logging then we can't return a valid pointer but it's also not an error so we return NULL. It's a special case of success. In this situation sched->ops->run_job(s_job); appears to only ever return NULL and it's not a special case of success, it's a regular old error. I guess we are transitioning from returning NULL to returning error pointers? So we should just do something like: fence = sched->ops->run_job(s_job); /* FIXME: Oct 2019: Remove this code when fence can't be NULL. */ if (!fence) fence = ERR_PTR(-EINVAL); if (IS_ERR(fence)) { ... regards, dan carpenter
On 10/29/19 2:03 PM, Dan Carpenter wrote: > On Tue, Oct 29, 2019 at 11:04:44AM -0400, Andrey Grodzovsky wrote: >> Fix a static code checker warning. >> >> Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com> >> --- >> drivers/gpu/drm/scheduler/sched_main.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c >> index f39b97e..898b0c9 100644 >> --- a/drivers/gpu/drm/scheduler/sched_main.c >> +++ b/drivers/gpu/drm/scheduler/sched_main.c >> @@ -497,7 +497,7 @@ void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched) >> fence = sched->ops->run_job(s_job); >> >> if (IS_ERR_OR_NULL(fence)) { >> s_job->s_fence->parent = NULL; >> - dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); >> + dma_fence_set_error(&s_fence->finished, PTR_ERR_OR_ZERO(fence)); > I feel like I should explain better. It's generally bad to mix NULL and > error pointers. The situation where you would do it is when NULL is a > special case of success. A typical situation is you request a feature, > like maybe logging for example: > > p = get_logger(); > > If there isn't enough memory then get_logger() returns ERR_PTR(-ENOMEM); > but if the user has disabled logging then we can't return a valid > pointer but it's also not an error so we return NULL. It's a special > case of success. > > In this situation sched->ops->run_job(s_job); appears to only ever > return NULL and it's not a special case of success, it's a regular old > error. I guess we are transitioning from returning NULL to returning > error pointers? No, check patch 'drm/amdgpu: If amdgpu_ib_schedule fails return back the error.' , amdgpu_job_run will pack an actual error code into ERR_PTR Andrey > > So we should just do something like: > > fence = sched->ops->run_job(s_job); > > /* FIXME: Oct 2019: Remove this code when fence can't be NULL. */ > if (!fence) > fence = ERR_PTR(-EINVAL); > > if (IS_ERR(fence)) { > ... > > regards, > dan carpenter >
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c index f39b97e..898b0c9 100644 --- a/drivers/gpu/drm/scheduler/sched_main.c +++ b/drivers/gpu/drm/scheduler/sched_main.c @@ -497,7 +497,7 @@ void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched) if (IS_ERR_OR_NULL(fence)) { s_job->s_fence->parent = NULL; - dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); + dma_fence_set_error(&s_fence->finished, PTR_ERR_OR_ZERO(fence)); } else { s_job->s_fence->parent = fence; } @@ -742,7 +742,7 @@ static int drm_sched_main(void *param) dma_fence_put(fence); } else { - dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); + dma_fence_set_error(&s_fence->finished, PTR_ERR_OR_ZERO(fence)); drm_sched_process_job(NULL, &sched_job->cb); }
Fix a static code checker warning. Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com> --- drivers/gpu/drm/scheduler/sched_main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)