similar to: [PATCH 2/6] drm/nouveau/svm: remove unused but set variables

clang with W=1 reports drivers/gpu/drm/nouveau/nouveau_svm.c:929:6: error: variable 'ret' set but not used [-Werror,-Wunused-but-set-variable] int ret; ^ This variable is not used so remove it. Signed-off-by: Tom Rix <trix at redhat.com> --- drivers/gpu/drm/nouveau/nouveau_svm.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git

On Wed, Aug 07, 2019 at 08:02:14AM -0700, Ralph Campbell wrote: > When memory is migrated to the GPU it is likely to be accessed by GPU > code soon afterwards. Instead of waiting for a GPU fault, map the > migrated memory into the GPU page tables with the same access permissions > as the source CPU page table entries. This preserves copy on write > semantics. > >

On 8/8/19 12:07 AM, Christoph Hellwig wrote: > On Wed, Aug 07, 2019 at 08:02:14AM -0700, Ralph Campbell wrote: >> When memory is migrated to the GPU it is likely to be accessed by GPU >> code soon afterwards. Instead of waiting for a GPU fault, map the >> migrated memory into the GPU page tables with the same access permissions >> as the source CPU page table entries.

When memory is migrated to the GPU, it is likely to be accessed by GPU code soon afterwards. Instead of waiting for a GPU fault, map the migrated memory into the GPU page tables with the same access permissions as the source CPU page table entries. This preserves copy on write semantics. Signed-off-by: Ralph Campbell <rcampbell at nvidia.com> Cc: Christoph Hellwig <hch at lst.de> Cc:

On Wed, Aug 07, 2019 at 08:02:14AM -0700, Ralph Campbell wrote: > When memory is migrated to the GPU it is likely to be accessed by GPU > code soon afterwards. Instead of waiting for a GPU fault, map the > migrated memory into the GPU page tables with the same access permissions > as the source CPU page table entries. This preserves copy on write > semantics. > >

Use the new MMU_NOTIFY_MIGRATE event to skip GPU MMU invalidations of device private memory and handle the invalidation in the driver as part of migrating device private memory. Signed-off-by: Ralph Campbell <rcampbell at nvidia.com> --- drivers/gpu/drm/nouveau/nouveau_dmem.c | 15 ++++++++++++--- drivers/gpu/drm/nouveau/nouveau_svm.c | 21 +++++++++------------

On 3/3/20 4:42 AM, Jason Gunthorpe wrote: > On Mon, Mar 02, 2020 at 05:00:23PM -0800, Ralph Campbell wrote: >> When memory is migrated to the GPU, it is likely to be accessed by GPU >> code soon afterwards. Instead of waiting for a GPU fault, map the >> migrated memory into the GPU page tables with the same access permissions >> as the source CPU page table entries. This

When memory is migrated to the GPU it is likely to be accessed by GPU code soon afterwards. Instead of waiting for a GPU fault, map the migrated memory into the GPU page tables with the same access permissions as the source CPU page table entries. This preserves copy on write semantics. Signed-off-by: Ralph Campbell <rcampbell at nvidia.com> Cc: Christoph Hellwig <hch at lst.de> Cc:

From: Ralph Campbell <rcampbell at nvidia.com> [ Upstream commit 822cab6150d3002952407a8297ff5a0d32bb7b54 ] When migrating system memory to GPU memory, check that SVM has been enabled. Even though most errors can be ignored since migration is a performance optimization, return an error because this is a violation of the API. Signed-off-by: Ralph Campbell <rcampbell at nvidia.com>

From: Ralph Campbell <rcampbell at nvidia.com> [ Upstream commit 822cab6150d3002952407a8297ff5a0d32bb7b54 ] When migrating system memory to GPU memory, check that SVM has been enabled. Even though most errors can be ignored since migration is a performance optimization, return an error because this is a violation of the API. Signed-off-by: Ralph Campbell <rcampbell at nvidia.com>

From: Ralph Campbell <rcampbell at nvidia.com> [ Upstream commit 822cab6150d3002952407a8297ff5a0d32bb7b54 ] When migrating system memory to GPU memory, check that SVM has been enabled. Even though most errors can be ignored since migration is a performance optimization, return an error because this is a violation of the API. Signed-off-by: Ralph Campbell <rcampbell at nvidia.com>

From: Jason Gunthorpe <jgg at mellanox.com> There is no reason to get the invalidate_range_start() callback via an indirection through hmm_mirror, just register a normal notifier directly. Cc: Ben Skeggs <bskeggs at redhat.com> Cc: dri-devel at lists.freedesktop.org Cc: nouveau at lists.freedesktop.org Cc: Ralph Campbell <rcampbell at nvidia.com> Signed-off-by: Jason Gunthorpe

Update nouveau to only use the mmu interval notifiers. Signed-off-by: Ralph Campbell <rcampbell at nvidia.com> --- drivers/gpu/drm/nouveau/nouveau_svm.c | 313 +++++++++++++++++--------- 1 file changed, 201 insertions(+), 112 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c index df9bf1fd1bc0..0343e48d41d7 100644 ---

From: Jason Gunthorpe <jgg at mellanox.com> Remove the hmm_mirror object and use the mmu_range_notifier API instead for the range, and use the normal mmu_notifier API for the general invalidation callback. While here re-organize the pagefault path so the locking pattern is clear. nouveau is the only driver that uses a temporary range object and instead forwards nearly every invalidation

The SVM page fault handler groups faults into a range of contiguous virtual addresses and requests hmm_range_fault() to populate and return the page frame number of system memory mapped by the CPU. In preparation for supporting large pages to be mapped by the GPU, process faults one page at a time. In addition, use the hmm_range default_flags to fix a corner case where the input hmm_pfns array is

The SVM page fault handler groups faults into a range of contiguous virtual addresses and requests hmm_range_fault() to populate and return the page frame number of system memory mapped by the CPU. In preparation for supporting large pages to be mapped by the GPU, process faults one page at a time. In addition, use the hmm_range default_flags to fix a corner case where the input hmm_pfns array is

On 1/14/20 5:00 AM, Jason Gunthorpe wrote: > On Mon, Jan 13, 2020 at 02:47:02PM -0800, Ralph Campbell wrote: >> void >> nouveau_svmm_fini(struct nouveau_svmm **psvmm) >> { >> struct nouveau_svmm *svmm = *psvmm; >> + struct mmu_interval_notifier *mni; >> + >> if (svmm) { >> mutex_lock(&svmm->mutex); >> + while (true) {

We'll need the nouveau_svmm structure to improve the function soon. For now this allows using the svmm->mm reference to unlock the mmap_sem, and thus the same dereference chain that the caller uses to lock and unlock it. Signed-off-by: Christoph Hellwig <hch at lst.de> --- drivers/gpu/drm/nouveau/nouveau_svm.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff

On Mon, Jan 13, 2020 at 02:47:02PM -0800, Ralph Campbell wrote: > void > nouveau_svmm_fini(struct nouveau_svmm **psvmm) > { > struct nouveau_svmm *svmm = *psvmm; > + struct mmu_interval_notifier *mni; > + > if (svmm) { > mutex_lock(&svmm->mutex); > + while (true) { > + mni = mmu_interval_notifier_find(svmm->mm, > +

This addresses the following gcc warning with "make W=1": drivers/gpu/drm/nouveau/nouveau_svm.c: In function ?nouveau_pfns_map?: drivers/gpu/drm/nouveau/nouveau_svm.c:818:6: warning: variable ?ret? set but not used [-Wunused-but-set-variable] 818 | int ret; | ^~~ Reported-by: Hulk Robot <hulkci at huawei.com> Signed-off-by: Jason Yan <yanaijie at huawei.com>