Re: [PATCH v3 4/7] mm: unify SLAB and SLUB page accounting
From: Shakeel Butt <hidden>
Date: 2019-05-11 00:33:32
Also in:
linux-mm, lkml
Possibly related (same subject, not in this thread)
- 2019-05-13 · Re: [PATCH v3 4/7] mm: unify SLAB and SLUB page accounting · Christopher Lameter <hidden>
From: Roman Gushchin <redacted> Date: Wed, May 8, 2019 at 1:40 PM To: Andrew Morton, Shakeel Butt Cc: <redacted>, <redacted>, [off-list ref], Johannes Weiner, Michal Hocko, Rik van Riel, Christoph Lameter, Vladimir Davydov, [off-list ref], Roman Gushchin
Currently the page accounting code is duplicated in SLAB and SLUB internals. Let's move it into new (un)charge_slab_page helpers in the slab_common.c file. These helpers will be responsible for statistics (global and memcg-aware) and memcg charging. So they are replacing direct memcg_(un)charge_slab() calls. Signed-off-by: Roman Gushchin <redacted>
Reviewed-by: Shakeel Butt <redacted>
quoted hunk
--- mm/slab.c | 19 +++---------------- mm/slab.h | 25 +++++++++++++++++++++++++ mm/slub.c | 14 ++------------ 3 files changed, 30 insertions(+), 28 deletions(-)diff --git a/mm/slab.c b/mm/slab.c index 83000e46b870..32e6af9ed9af 100644 --- a/mm/slab.c +++ b/mm/slab.c@@ -1389,7 +1389,6 @@ static struct page *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid) { struct page *page; - int nr_pages; flags |= cachep->allocflags;@@ -1399,17 +1398,11 @@ static struct page *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, return NULL; } - if (memcg_charge_slab(page, flags, cachep->gfporder, cachep)) { + if (charge_slab_page(page, flags, cachep->gfporder, cachep)) { __free_pages(page, cachep->gfporder); return NULL; } - nr_pages = (1 << cachep->gfporder); - if (cachep->flags & SLAB_RECLAIM_ACCOUNT) - mod_lruvec_page_state(page, NR_SLAB_RECLAIMABLE, nr_pages); - else - mod_lruvec_page_state(page, NR_SLAB_UNRECLAIMABLE, nr_pages); - __SetPageSlab(page); /* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */ if (sk_memalloc_socks() && page_is_pfmemalloc(page))@@ -1424,12 +1417,6 @@ static struct page *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, static void kmem_freepages(struct kmem_cache *cachep, struct page *page) { int order = cachep->gfporder; - unsigned long nr_freed = (1 << order); - - if (cachep->flags & SLAB_RECLAIM_ACCOUNT) - mod_lruvec_page_state(page, NR_SLAB_RECLAIMABLE, -nr_freed); - else - mod_lruvec_page_state(page, NR_SLAB_UNRECLAIMABLE, -nr_freed); BUG_ON(!PageSlab(page)); __ClearPageSlabPfmemalloc(page);@@ -1438,8 +1425,8 @@ static void kmem_freepages(struct kmem_cache *cachep, struct page *page) page->mapping = NULL; if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += nr_freed; - memcg_uncharge_slab(page, order, cachep); + current->reclaim_state->reclaimed_slab += 1 << order; + uncharge_slab_page(page, order, cachep); __free_pages(page, order); }diff --git a/mm/slab.h b/mm/slab.h index 4a261c97c138..c9a31120fa1d 100644 --- a/mm/slab.h +++ b/mm/slab.h@@ -205,6 +205,12 @@ ssize_t slabinfo_write(struct file *file, const char __user *buffer, void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **); int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **); +static inline int cache_vmstat_idx(struct kmem_cache *s) +{ + return (s->flags & SLAB_RECLAIM_ACCOUNT) ? + NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE; +} + #ifdef CONFIG_MEMCG_KMEM /* List of all root caches. */@@ -352,6 +358,25 @@ static inline void memcg_link_cache(struct kmem_cache *s, #endif /* CONFIG_MEMCG_KMEM */ +static __always_inline int charge_slab_page(struct page *page, + gfp_t gfp, int order, + struct kmem_cache *s) +{ + int ret = memcg_charge_slab(page, gfp, order, s); + + if (!ret) + mod_lruvec_page_state(page, cache_vmstat_idx(s), 1 << order); + + return ret; +} + +static __always_inline void uncharge_slab_page(struct page *page, int order, + struct kmem_cache *s) +{ + mod_lruvec_page_state(page, cache_vmstat_idx(s), -(1 << order)); + memcg_uncharge_slab(page, order, s); +} + static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) { struct kmem_cache *cachep;diff --git a/mm/slub.c b/mm/slub.c index 43c34d54ad86..9ec25a588bdd 100644 --- a/mm/slub.c +++ b/mm/slub.c@@ -1494,7 +1494,7 @@ static inline struct page *alloc_slab_page(struct kmem_cache *s, else page = __alloc_pages_node(node, flags, order); - if (page && memcg_charge_slab(page, flags, order, s)) { + if (page && charge_slab_page(page, flags, order, s)) { __free_pages(page, order); page = NULL; }@@ -1687,11 +1687,6 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) if (!page) return NULL; - mod_lruvec_page_state(page, - (s->flags & SLAB_RECLAIM_ACCOUNT) ? - NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, - 1 << oo_order(oo)); - inc_slabs_node(s, page_to_nid(page), page->objects); return page;@@ -1725,18 +1720,13 @@ static void __free_slab(struct kmem_cache *s, struct page *page) check_object(s, page, p, SLUB_RED_INACTIVE); } - mod_lruvec_page_state(page, - (s->flags & SLAB_RECLAIM_ACCOUNT) ? - NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, - -pages); - __ClearPageSlabPfmemalloc(page); __ClearPageSlab(page); page->mapping = NULL; if (current->reclaim_state) current->reclaim_state->reclaimed_slab += pages; - memcg_uncharge_slab(page, order, s); + uncharge_slab_page(page, order, s); __free_pages(page, order); } --2.20.1