| Message ID | 20180926161839.4549-12-thellstrom@vmware.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [-next,01/18] drm/vmwgfx: Add a validation module v2 | expand |
Am 26.09.2018 um 18:18 schrieb Thomas Hellstrom: > Export ttm_bo_reference_unless_doomed() to be used when looking up buffer > objects that are removed from the lookup structure in the destructor. > > Cc: Christian König <christian.koenig@amd.com> > Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> > Reviewed-by: Sinclair Yeh <syeh@vmware.com> > --- > drivers/gpu/drm/ttm/ttm_bo_vm.c | 3 +-- > include/drm/ttm/ttm_bo_api.h | 18 ++++++++++++++++++ > 2 files changed, 19 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c > index 6fe91c1b692d..ec4b09366213 100644 > --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c > +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c > @@ -409,8 +409,7 @@ static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_bo_device *bdev, > node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages); > if (likely(node)) { > bo = container_of(node, struct ttm_buffer_object, vma_node); > - if (!kref_get_unless_zero(&bo->kref)) > - bo = NULL; > + bo = ttm_bo_reference_unless_doomed(bo); > } > > drm_vma_offset_unlock_lookup(&bdev->vma_manager); > diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h > index 8c19470785e2..b6bf6b086576 100644 > --- a/include/drm/ttm/ttm_bo_api.h > +++ b/include/drm/ttm/ttm_bo_api.h > @@ -312,6 +312,24 @@ ttm_bo_reference(struct ttm_buffer_object *bo) > return bo; > } > > +/** > + * ttm_bo_reference_unless_doomed - reference a struct ttm_buffer_object unless > + * its refcount has already reached zero. > + * @bo: The buffer object. > + * > + * Used to reference a TTM buffer object in lookups where the object is removed > + * from the lookup structure during the destructor and for RCU lookups. > + * > + * Returns: @bo if the referencing was successful, NULL otherwise. > + */ > +static inline __must_check struct ttm_buffer_object * > +ttm_bo_reference_unless_doomed(struct ttm_buffer_object *bo) Please name that ttm_bo_get_rcu(), we are in the process of renaming ttm_bo_reference into ttm_bo_get as well. Christian. > +{ > + if (!kref_get_unless_zero(&bo->kref)) > + return NULL; > + return bo; > +} > + > /** > * ttm_bo_wait - wait for buffer idle. > *
On 09/26/2018 06:35 PM, Christian König wrote: > Am 26.09.2018 um 18:18 schrieb Thomas Hellstrom: >> Export ttm_bo_reference_unless_doomed() to be used when looking up >> buffer >> objects that are removed from the lookup structure in the destructor. >> >> Cc: Christian König <christian.koenig@amd.com> >> Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> >> Reviewed-by: Sinclair Yeh <syeh@vmware.com> >> --- >> drivers/gpu/drm/ttm/ttm_bo_vm.c | 3 +-- >> include/drm/ttm/ttm_bo_api.h | 18 ++++++++++++++++++ >> 2 files changed, 19 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c >> b/drivers/gpu/drm/ttm/ttm_bo_vm.c >> index 6fe91c1b692d..ec4b09366213 100644 >> --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c >> +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c >> @@ -409,8 +409,7 @@ static struct ttm_buffer_object >> *ttm_bo_vm_lookup(struct ttm_bo_device *bdev, >> node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, >> pages); >> if (likely(node)) { >> bo = container_of(node, struct ttm_buffer_object, vma_node); >> - if (!kref_get_unless_zero(&bo->kref)) >> - bo = NULL; >> + bo = ttm_bo_reference_unless_doomed(bo); >> } >> drm_vma_offset_unlock_lookup(&bdev->vma_manager); >> diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h >> index 8c19470785e2..b6bf6b086576 100644 >> --- a/include/drm/ttm/ttm_bo_api.h >> +++ b/include/drm/ttm/ttm_bo_api.h >> @@ -312,6 +312,24 @@ ttm_bo_reference(struct ttm_buffer_object *bo) >> return bo; >> } >> +/** >> + * ttm_bo_reference_unless_doomed - reference a struct >> ttm_buffer_object unless >> + * its refcount has already reached zero. >> + * @bo: The buffer object. >> + * >> + * Used to reference a TTM buffer object in lookups where the object >> is removed >> + * from the lookup structure during the destructor and for RCU lookups. >> + * >> + * Returns: @bo if the referencing was successful, NULL otherwise. >> + */ >> +static inline __must_check struct ttm_buffer_object * >> +ttm_bo_reference_unless_doomed(struct ttm_buffer_object *bo) > > Please name that ttm_bo_get_rcu(), we are in the process of renaming > ttm_bo_reference into ttm_bo_get as well. Could we call it ttm_bo_get_unless_doomed() or ttm_bo_get_unless_zero() to be even more consistent. (It's not restricted to rcu as the VM usage shows). Also "doomed" is more relevant for objects, "zero" is more relevant for the refcount itself? /Thomas > > Christian. > >> +{ >> + if (!kref_get_unless_zero(&bo->kref)) >> + return NULL; >> + return bo; >> +} >> + >> /** >> * ttm_bo_wait - wait for buffer idle. >> * >
Am 26.09.2018 um 18:43 schrieb Thomas Hellstrom: > On 09/26/2018 06:35 PM, Christian König wrote: >> Am 26.09.2018 um 18:18 schrieb Thomas Hellstrom: >>> Export ttm_bo_reference_unless_doomed() to be used when looking up >>> buffer >>> objects that are removed from the lookup structure in the destructor. >>> >>> Cc: Christian König <christian.koenig@amd.com> >>> Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> >>> Reviewed-by: Sinclair Yeh <syeh@vmware.com> >>> --- >>> drivers/gpu/drm/ttm/ttm_bo_vm.c | 3 +-- >>> include/drm/ttm/ttm_bo_api.h | 18 ++++++++++++++++++ >>> 2 files changed, 19 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c >>> b/drivers/gpu/drm/ttm/ttm_bo_vm.c >>> index 6fe91c1b692d..ec4b09366213 100644 >>> --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c >>> +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c >>> @@ -409,8 +409,7 @@ static struct ttm_buffer_object >>> *ttm_bo_vm_lookup(struct ttm_bo_device *bdev, >>> node = drm_vma_offset_lookup_locked(&bdev->vma_manager, >>> offset, pages); >>> if (likely(node)) { >>> bo = container_of(node, struct ttm_buffer_object, vma_node); >>> - if (!kref_get_unless_zero(&bo->kref)) >>> - bo = NULL; >>> + bo = ttm_bo_reference_unless_doomed(bo); >>> } >>> drm_vma_offset_unlock_lookup(&bdev->vma_manager); >>> diff --git a/include/drm/ttm/ttm_bo_api.h >>> b/include/drm/ttm/ttm_bo_api.h >>> index 8c19470785e2..b6bf6b086576 100644 >>> --- a/include/drm/ttm/ttm_bo_api.h >>> +++ b/include/drm/ttm/ttm_bo_api.h >>> @@ -312,6 +312,24 @@ ttm_bo_reference(struct ttm_buffer_object *bo) >>> return bo; >>> } >>> +/** >>> + * ttm_bo_reference_unless_doomed - reference a struct >>> ttm_buffer_object unless >>> + * its refcount has already reached zero. >>> + * @bo: The buffer object. >>> + * >>> + * Used to reference a TTM buffer object in lookups where the >>> object is removed >>> + * from the lookup structure during the destructor and for RCU >>> lookups. >>> + * >>> + * Returns: @bo if the referencing was successful, NULL otherwise. >>> + */ >>> +static inline __must_check struct ttm_buffer_object * >>> +ttm_bo_reference_unless_doomed(struct ttm_buffer_object *bo) >> >> Please name that ttm_bo_get_rcu(), we are in the process of renaming >> ttm_bo_reference into ttm_bo_get as well. > > Could we call it ttm_bo_get_unless_doomed() or > ttm_bo_get_unless_zero() to be even more consistent. (It's not > restricted to rcu as the VM usage shows). Also "doomed" is more > relevant for objects, "zero" is more relevant for the refcount itself? ttm_bo_get_unless_zero() is fine with me as well. Christian. > > /Thomas > > > >> >> Christian. >> >>> +{ >>> + if (!kref_get_unless_zero(&bo->kref)) >>> + return NULL; >>> + return bo; >>> +} >>> + >>> /** >>> * ttm_bo_wait - wait for buffer idle. >>> * >> >
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index 6fe91c1b692d..ec4b09366213 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -409,8 +409,7 @@ static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_bo_device *bdev, node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages); if (likely(node)) { bo = container_of(node, struct ttm_buffer_object, vma_node); - if (!kref_get_unless_zero(&bo->kref)) - bo = NULL; + bo = ttm_bo_reference_unless_doomed(bo); } drm_vma_offset_unlock_lookup(&bdev->vma_manager); diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h index 8c19470785e2..b6bf6b086576 100644 --- a/include/drm/ttm/ttm_bo_api.h +++ b/include/drm/ttm/ttm_bo_api.h @@ -312,6 +312,24 @@ ttm_bo_reference(struct ttm_buffer_object *bo) return bo; } +/** + * ttm_bo_reference_unless_doomed - reference a struct ttm_buffer_object unless + * its refcount has already reached zero. + * @bo: The buffer object. + * + * Used to reference a TTM buffer object in lookups where the object is removed + * from the lookup structure during the destructor and for RCU lookups. + * + * Returns: @bo if the referencing was successful, NULL otherwise. + */ +static inline __must_check struct ttm_buffer_object * +ttm_bo_reference_unless_doomed(struct ttm_buffer_object *bo) +{ + if (!kref_get_unless_zero(&bo->kref)) + return NULL; + return bo; +} + /** * ttm_bo_wait - wait for buffer idle. *