| Message ID | 20190701062020.19239-19-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/22] mm/hmm.c: suppress compilation warnings when CONFIG_HUGETLB_PAGE is not set | expand |
On 6/30/19 11:20 PM, Christoph Hellwig wrote: > Checking range->valid is trivial and has no meaningful cost, but > nicely simplifies the fastpath in typical callers. Also remove the > hmm_vma_range_done function, which now is a trivial wrapper around > hmm_range_unregister. > > Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ralph Campbell <rcampbell@nvidia.com> > --- > drivers/gpu/drm/nouveau/nouveau_svm.c | 2 +- > include/linux/hmm.h | 11 +---------- > mm/hmm.c | 6 +++++- > 3 files changed, 7 insertions(+), 12 deletions(-) > > diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c > index 8c92374afcf2..9d40114d7949 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_svm.c > +++ b/drivers/gpu/drm/nouveau/nouveau_svm.c > @@ -652,7 +652,7 @@ nouveau_svm_fault(struct nvif_notify *notify) > ret = hmm_vma_fault(&svmm->mirror, &range, true); > if (ret == 0) { > mutex_lock(&svmm->mutex); > - if (!hmm_vma_range_done(&range)) { > + if (!hmm_range_unregister(&range)) { > mutex_unlock(&svmm->mutex); > goto again; > } > diff --git a/include/linux/hmm.h b/include/linux/hmm.h > index 0fa8ea34ccef..4b185d286c3b 100644 > --- a/include/linux/hmm.h > +++ b/include/linux/hmm.h > @@ -465,7 +465,7 @@ int hmm_range_register(struct hmm_range *range, > unsigned long start, > unsigned long end, > unsigned page_shift); > -void hmm_range_unregister(struct hmm_range *range); > +bool hmm_range_unregister(struct hmm_range *range); > long hmm_range_snapshot(struct hmm_range *range); > long hmm_range_fault(struct hmm_range *range, bool block); > long hmm_range_dma_map(struct hmm_range *range, > @@ -487,15 +487,6 @@ long hmm_range_dma_unmap(struct hmm_range *range, > */ > #define HMM_RANGE_DEFAULT_TIMEOUT 1000 > > -/* This is a temporary helper to avoid merge conflict between trees. */ > -static inline bool hmm_vma_range_done(struct hmm_range *range) > -{ > - bool ret = hmm_range_valid(range); > - > - hmm_range_unregister(range); > - return ret; > -} > - > /* This is a temporary helper to avoid merge conflict between trees. */ > static inline int hmm_vma_fault(struct hmm_mirror *mirror, > struct hmm_range *range, bool block) > diff --git a/mm/hmm.c b/mm/hmm.c > index de35289df20d..c85ed7d4e2ce 100644 > --- a/mm/hmm.c > +++ b/mm/hmm.c > @@ -920,11 +920,14 @@ EXPORT_SYMBOL(hmm_range_register); > * > * Range struct is used to track updates to the CPU page table after a call to > * hmm_range_register(). See include/linux/hmm.h for how to use it. > + * > + * Returns if the range was still valid at the time of unregistering. Since this is an exported function, we should have kernel-doc comments. That is probably a separate patch but at least this line could be: Return: True if the range was still valid at the time of unregistering. > */ > -void hmm_range_unregister(struct hmm_range *range) > +bool hmm_range_unregister(struct hmm_range *range) > { > struct hmm *hmm = range->hmm; > unsigned long flags; > + bool ret = range->valid; > > spin_lock_irqsave(&hmm->ranges_lock, flags); > list_del_init(&range->list); > @@ -941,6 +944,7 @@ void hmm_range_unregister(struct hmm_range *range) > */ > range->valid = false; > memset(&range->hmm, POISON_INUSE, sizeof(range->hmm)); > + return ret; > } > EXPORT_SYMBOL(hmm_range_unregister); > >
diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c index 8c92374afcf2..9d40114d7949 100644 --- a/drivers/gpu/drm/nouveau/nouveau_svm.c +++ b/drivers/gpu/drm/nouveau/nouveau_svm.c @@ -652,7 +652,7 @@ nouveau_svm_fault(struct nvif_notify *notify) ret = hmm_vma_fault(&svmm->mirror, &range, true); if (ret == 0) { mutex_lock(&svmm->mutex); - if (!hmm_vma_range_done(&range)) { + if (!hmm_range_unregister(&range)) { mutex_unlock(&svmm->mutex); goto again; } diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 0fa8ea34ccef..4b185d286c3b 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -465,7 +465,7 @@ int hmm_range_register(struct hmm_range *range, unsigned long start, unsigned long end, unsigned page_shift); -void hmm_range_unregister(struct hmm_range *range); +bool hmm_range_unregister(struct hmm_range *range); long hmm_range_snapshot(struct hmm_range *range); long hmm_range_fault(struct hmm_range *range, bool block); long hmm_range_dma_map(struct hmm_range *range, @@ -487,15 +487,6 @@ long hmm_range_dma_unmap(struct hmm_range *range, */ #define HMM_RANGE_DEFAULT_TIMEOUT 1000 -/* This is a temporary helper to avoid merge conflict between trees. */ -static inline bool hmm_vma_range_done(struct hmm_range *range) -{ - bool ret = hmm_range_valid(range); - - hmm_range_unregister(range); - return ret; -} - /* This is a temporary helper to avoid merge conflict between trees. */ static inline int hmm_vma_fault(struct hmm_mirror *mirror, struct hmm_range *range, bool block) diff --git a/mm/hmm.c b/mm/hmm.c index de35289df20d..c85ed7d4e2ce 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -920,11 +920,14 @@ EXPORT_SYMBOL(hmm_range_register); * * Range struct is used to track updates to the CPU page table after a call to * hmm_range_register(). See include/linux/hmm.h for how to use it. + * + * Returns if the range was still valid at the time of unregistering. */ -void hmm_range_unregister(struct hmm_range *range) +bool hmm_range_unregister(struct hmm_range *range) { struct hmm *hmm = range->hmm; unsigned long flags; + bool ret = range->valid; spin_lock_irqsave(&hmm->ranges_lock, flags); list_del_init(&range->list); @@ -941,6 +944,7 @@ void hmm_range_unregister(struct hmm_range *range) */ range->valid = false; memset(&range->hmm, POISON_INUSE, sizeof(range->hmm)); + return ret; } EXPORT_SYMBOL(hmm_range_unregister);
Checking range->valid is trivial and has no meaningful cost, but nicely simplifies the fastpath in typical callers. Also remove the hmm_vma_range_done function, which now is a trivial wrapper around hmm_range_unregister. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/gpu/drm/nouveau/nouveau_svm.c | 2 +- include/linux/hmm.h | 11 +---------- mm/hmm.c | 6 +++++- 3 files changed, 7 insertions(+), 12 deletions(-)