From 9d0a16658f840335325508e06a797be1883e6c56 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 6 Aug 2019 19:05:39 +0300 Subject: [PATCH] amdgpu: remove -EAGAIN handling for hmm_range_fault hmm_range_fault can only return -EAGAIN if called with the HMM_FAULT_ALLOW_RETRY flag, which amdgpu never does. Remove the handling for the -EAGAIN case with its non-standard locking scheme. Link: https://lore.kernel.org/r/20190806160554.14046-2-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Reviewed-by: Felix Kuehling Signed-off-by: Jason Gunthorpe --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 23 +++-------------------- 1 file changed, 3 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index 12a59ac83f72..f0821638bbc6 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -778,7 +778,6 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) struct hmm_range *range; unsigned long i; uint64_t *pfns; - int retry = 0; int r = 0; if (!mm) /* Happens during process shutdown */ @@ -822,7 +821,6 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) hmm_range_register(range, mirror, start, start + ttm->num_pages * PAGE_SIZE, PAGE_SHIFT); -retry: /* * Just wait for range to be valid, safe to ignore return value as we * will use the return value of hmm_range_fault() below under the @@ -831,24 +829,12 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT); down_read(&mm->mmap_sem); - r = hmm_range_fault(range, 0); - if (unlikely(r < 0)) { - if (likely(r == -EAGAIN)) { - /* - * return -EAGAIN, mmap_sem is dropped - */ - if (retry++ < MAX_RETRY_HMM_RANGE_FAULT) - goto retry; - else - pr_err("Retry hmm fault too many times\n"); - } - - goto out_up_read; - } - up_read(&mm->mmap_sem); + if (unlikely(r < 0)) + goto out_free_pfns; + for (i = 0; i < ttm->num_pages; i++) { pages[i] = hmm_device_entry_to_page(range, pfns[i]); if (unlikely(!pages[i])) { @@ -864,9 +850,6 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) return 0; -out_up_read: - if (likely(r != -EAGAIN)) - up_read(&mm->mmap_sem); out_free_pfns: hmm_range_unregister(range); kvfree(pfns); -- 2.45.2