From e9a6effa500526e2a19d5ad042cb758b55b1ef93 Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Wed, 15 Nov 2017 17:33:15 -0800 Subject: mm, swap: fix false error message in __swp_swapcount() When a page fault occurs for a swap entry, the physical swap readahead (not the VMA base swap readahead) may readahead several swap entries after the fault swap entry. The readahead algorithm calculates some of the swap entries to readahead via increasing the offset of the fault swap entry without checking whether they are beyond the end of the swap device and it relys on the __swp_swapcount() and swapcache_prepare() to check it. Although __swp_swapcount() checks for the swap entry passed in, it will complain with the error message as follow for the expected invalid swap entry. This may make the end users confused. swap_info_get: Bad swap offset entry 0200f8a7 To fix the false error message, the swap entry checking is added in swapin_readahead() to avoid to pass the out-of-bound swap entries and the swap entry reserved for the swap header to __swp_swapcount() and swapcache_prepare(). Link: http://lkml.kernel.org/r/20171102054225.22897-1-ying.huang@intel.com Fixes: e8c26ab60598 ("mm/swap: skip readahead for unreferenced swap slots") Signed-off-by: "Huang, Ying" Reported-by: Christian Kujau Acked-by: Minchan Kim Suggested-by: Minchan Kim Cc: Tim Chen Cc: Michal Hocko Cc: Hugh Dickins Cc: [4.11+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/swap_state.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'mm/swap_state.c') diff --git a/mm/swap_state.c b/mm/swap_state.c index 326439428daf..f2face8b889e 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -559,6 +559,7 @@ struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask, unsigned long offset = entry_offset; unsigned long start_offset, end_offset; unsigned long mask; + struct swap_info_struct *si = swp_swap_info(entry); struct blk_plug plug; bool do_poll = true, page_allocated; @@ -572,6 +573,8 @@ struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask, end_offset = offset | mask; if (!start_offset) /* First page is swap header. */ start_offset++; + if (end_offset >= si->max) + end_offset = si->max - 1; blk_start_plug(&plug); for (offset = start_offset; offset <= end_offset ; offset++) { -- cgit v1.2.3-59-g8ed1b From 783cb68ee2d25d621326366c0b615bf2ccf3b402 Mon Sep 17 00:00:00 2001 From: Changbin Du Date: Wed, 15 Nov 2017 17:36:06 -0800 Subject: mm/swap_state.c: declare a few variables as __read_mostly These global variables are only set during initialization or rarely change, so declare them as __read_mostly. Link: http://lkml.kernel.org/r/1507802349-5554-1-git-send-email-changbin.du@intel.com Signed-off-by: Changbin Du Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/swap_state.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'mm/swap_state.c') diff --git a/mm/swap_state.c b/mm/swap_state.c index f2face8b889e..374d446f7a0a 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -36,9 +36,9 @@ static const struct address_space_operations swap_aops = { #endif }; -struct address_space *swapper_spaces[MAX_SWAPFILES]; -static unsigned int nr_swapper_spaces[MAX_SWAPFILES]; -bool swap_vma_readahead = true; +struct address_space *swapper_spaces[MAX_SWAPFILES] __read_mostly; +static unsigned int nr_swapper_spaces[MAX_SWAPFILES] __read_mostly; +bool swap_vma_readahead __read_mostly = true; #define SWAP_RA_WIN_SHIFT (PAGE_SHIFT / 2) #define SWAP_RA_HITS_MASK ((1UL << SWAP_RA_WIN_SHIFT) - 1) -- cgit v1.2.3-59-g8ed1b From c6f92f9fbe7dbcc8903a67229aa88b4077ae4422 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Wed, 15 Nov 2017 17:37:55 -0800 Subject: mm: remove cold parameter for release_pages All callers of release_pages claim the pages being released are cache hot. As no one cares about the hotness of pages being released to the allocator, just ditch the parameter. No performance impact is expected as the overhead is marginal. The parameter is removed simply because it is a bit stupid to have a useless parameter copied everywhere. Link: http://lkml.kernel.org/r/20171018075952.10627-7-mgorman@techsingularity.net Signed-off-by: Mel Gorman Acked-by: Vlastimil Babka Cc: Andi Kleen Cc: Dave Chinner Cc: Dave Hansen Cc: Jan Kara Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 6 ++---- drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 2 +- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 2 +- drivers/gpu/drm/etnaviv/etnaviv_gem.c | 6 +++--- drivers/gpu/drm/i915/i915_gem_userptr.c | 4 ++-- drivers/gpu/drm/radeon/radeon_ttm.c | 2 +- fs/fuse/dev.c | 2 +- include/linux/pagemap.h | 2 +- include/linux/swap.h | 2 +- mm/swap.c | 8 ++++---- mm/swap_state.c | 2 +- 11 files changed, 18 insertions(+), 20 deletions(-) (limited to 'mm/swap_state.c') diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c index 60d8bedb694d..cd664832f9e8 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c @@ -553,8 +553,7 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p, * invalidated it. Free it and try again */ release_pages(e->user_pages, - e->robj->tbo.ttm->num_pages, - false); + e->robj->tbo.ttm->num_pages); kvfree(e->user_pages); e->user_pages = NULL; } @@ -691,8 +690,7 @@ error_free_pages: continue; release_pages(e->user_pages, - e->robj->tbo.ttm->num_pages, - false); + e->robj->tbo.ttm->num_pages); kvfree(e->user_pages); } } diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c index 6149a47fe63d..0bda8f2a188a 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c @@ -347,7 +347,7 @@ int amdgpu_gem_userptr_ioctl(struct drm_device *dev, void *data, return 0; free_pages: - release_pages(bo->tbo.ttm->pages, bo->tbo.ttm->num_pages, false); + release_pages(bo->tbo.ttm->pages, bo->tbo.ttm->num_pages); unlock_mmap_sem: up_read(¤t->mm->mmap_sem); diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index bc746131987f..d792959fac43 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -659,7 +659,7 @@ int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages) return 0; release_pages: - release_pages(pages, pinned, 0); + release_pages(pages, pinned); return r; } diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.c b/drivers/gpu/drm/etnaviv/etnaviv_gem.c index 57881167ccd2..bcc8c2d7c7c9 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gem.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.c @@ -779,7 +779,7 @@ static struct page **etnaviv_gem_userptr_do_get_pages( up_read(&mm->mmap_sem); if (ret < 0) { - release_pages(pvec, pinned, 0); + release_pages(pvec, pinned); kvfree(pvec); return ERR_PTR(ret); } @@ -852,7 +852,7 @@ static int etnaviv_gem_userptr_get_pages(struct etnaviv_gem_object *etnaviv_obj) } } - release_pages(pvec, pinned, 0); + release_pages(pvec, pinned); kvfree(pvec); work = kmalloc(sizeof(*work), GFP_KERNEL); @@ -886,7 +886,7 @@ static void etnaviv_gem_userptr_release(struct etnaviv_gem_object *etnaviv_obj) if (etnaviv_obj->pages) { int npages = etnaviv_obj->base.size >> PAGE_SHIFT; - release_pages(etnaviv_obj->pages, npages, 0); + release_pages(etnaviv_obj->pages, npages); kvfree(etnaviv_obj->pages); } put_task_struct(etnaviv_obj->userptr.task); diff --git a/drivers/gpu/drm/i915/i915_gem_userptr.c b/drivers/gpu/drm/i915/i915_gem_userptr.c index 709efe2357ea..aa22361bd5a1 100644 --- a/drivers/gpu/drm/i915/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/i915_gem_userptr.c @@ -554,7 +554,7 @@ __i915_gem_userptr_get_pages_worker(struct work_struct *_work) } mutex_unlock(&obj->mm.lock); - release_pages(pvec, pinned, 0); + release_pages(pvec, pinned); kvfree(pvec); i915_gem_object_put(obj); @@ -668,7 +668,7 @@ i915_gem_userptr_get_pages(struct drm_i915_gem_object *obj) __i915_gem_userptr_set_active(obj, true); if (IS_ERR(pages)) - release_pages(pvec, pinned, 0); + release_pages(pvec, pinned); kvfree(pvec); return pages; diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c index bf69bf9086bf..1fdfc7a46072 100644 --- a/drivers/gpu/drm/radeon/radeon_ttm.c +++ b/drivers/gpu/drm/radeon/radeon_ttm.c @@ -597,7 +597,7 @@ release_sg: kfree(ttm->sg); release_pages: - release_pages(ttm->pages, pinned, 0); + release_pages(ttm->pages, pinned); return r; } diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index a42d89371748..17f0d05bfd4c 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -1636,7 +1636,7 @@ out_finish: static void fuse_retrieve_end(struct fuse_conn *fc, struct fuse_req *req) { - release_pages(req->pages, req->num_pages, false); + release_pages(req->pages, req->num_pages); } static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode, diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index e0f7181118fe..4c6790bb7afb 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -118,7 +118,7 @@ static inline void mapping_set_gfp_mask(struct address_space *m, gfp_t mask) m->gfp_mask = mask; } -void release_pages(struct page **pages, int nr, bool cold); +void release_pages(struct page **pages, int nr); /* * speculatively take a reference to a page. diff --git a/include/linux/swap.h b/include/linux/swap.h index 454f042bcdd5..c2b8128799c1 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -510,7 +510,7 @@ static inline struct swap_info_struct *swp_swap_info(swp_entry_t entry) #define free_page_and_swap_cache(page) \ put_page(page) #define free_pages_and_swap_cache(pages, nr) \ - release_pages((pages), (nr), false); + release_pages((pages), (nr)); static inline void show_swap_cache_info(void) { diff --git a/mm/swap.c b/mm/swap.c index 88a19b6cdf7c..29cf75f1a860 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -210,7 +210,7 @@ static void pagevec_lru_move_fn(struct pagevec *pvec, } if (pgdat) spin_unlock_irqrestore(&pgdat->lru_lock, flags); - release_pages(pvec->pages, pvec->nr, 0); + release_pages(pvec->pages, pvec->nr); pagevec_reinit(pvec); } @@ -740,7 +740,7 @@ void lru_add_drain_all(void) * Decrement the reference count on all the pages in @pages. If it * fell to zero, remove the page from the LRU and free it. */ -void release_pages(struct page **pages, int nr, bool cold) +void release_pages(struct page **pages, int nr) { int i; LIST_HEAD(pages_to_free); @@ -817,7 +817,7 @@ void release_pages(struct page **pages, int nr, bool cold) spin_unlock_irqrestore(&locked_pgdat->lru_lock, flags); mem_cgroup_uncharge_list(&pages_to_free); - free_hot_cold_page_list(&pages_to_free, cold); + free_hot_cold_page_list(&pages_to_free, 0); } EXPORT_SYMBOL(release_pages); @@ -837,7 +837,7 @@ void __pagevec_release(struct pagevec *pvec) lru_add_drain(); pvec->drained = true; } - release_pages(pvec->pages, pagevec_count(pvec), 0); + release_pages(pvec->pages, pagevec_count(pvec)); pagevec_reinit(pvec); } EXPORT_SYMBOL(__pagevec_release); diff --git a/mm/swap_state.c b/mm/swap_state.c index 374d446f7a0a..39ae7cfad90f 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -319,7 +319,7 @@ void free_pages_and_swap_cache(struct page **pages, int nr) lru_add_drain(); for (i = 0; i < nr; i++) free_swap_cache(pagep[i]); - release_pages(pagep, nr, false); + release_pages(pagep, nr); } /* -- cgit v1.2.3-59-g8ed1b