The patch titled Subject: mm: memcg: remove unused node/section info from pc->flags has been added to the -mm tree. Its filename is mm-memcg-remove-unused-node-section-info-from-pc-flags.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ From: Johannes Weiner <jweiner@xxxxxxxxxx> Subject: mm: memcg: remove unused node/section info from pc->flags To find the page corresponding to a certain page_cgroup, the pc->flags encoded the node or section ID with the base array to compare the pc pointer to. Now that the per-memory cgroup LRU lists link page descriptors directly, there is no longer any code that knows the struct page_cgroup of a PFN but not the struct page. Signed-off-by: Johannes Weiner <jweiner@xxxxxxxxxx> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Reviewed-by: Michal Hocko <mhocko@xxxxxxx> Reviewed-by: Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxx> Cc: "Kirill A. Shutemov" <kirill@xxxxxxxxxxxxx> Cc: Daisuke Nishimura <nishimura@xxxxxxxxxxxxxxxxx> Cc: Balbir Singh <bsingharora@xxxxxxxxx> Cc: Ying Han <yinghan@xxxxxxxxxx> Cc: Greg Thelen <gthelen@xxxxxxxxxx> Cc: Michel Lespinasse <walken@xxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Cc: Minchan Kim <minchan.kim@xxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/page_cgroup.h | 33 ------------------- mm/page_cgroup.c | 57 ++++------------------------------ 2 files changed, 7 insertions(+), 83 deletions(-) diff -puN include/linux/page_cgroup.h~mm-memcg-remove-unused-node-section-info-from-pc-flags include/linux/page_cgroup.h --- a/include/linux/page_cgroup.h~mm-memcg-remove-unused-node-section-info-from-pc-flags +++ a/include/linux/page_cgroup.h @@ -121,39 +121,6 @@ static inline void move_unlock_page_cgro local_irq_restore(*flags); } -#ifdef CONFIG_SPARSEMEM -#define PCG_ARRAYID_WIDTH SECTIONS_SHIFT -#else -#define PCG_ARRAYID_WIDTH NODES_SHIFT -#endif - -#if (PCG_ARRAYID_WIDTH > BITS_PER_LONG - NR_PCG_FLAGS) -#error Not enough space left in pc->flags to store page_cgroup array IDs -#endif - -/* pc->flags: ARRAY-ID | FLAGS */ - -#define PCG_ARRAYID_MASK ((1UL << PCG_ARRAYID_WIDTH) - 1) - -#define PCG_ARRAYID_OFFSET (BITS_PER_LONG - PCG_ARRAYID_WIDTH) -/* - * Zero the shift count for non-existent fields, to prevent compiler - * warnings and ensure references are optimized away. - */ -#define PCG_ARRAYID_SHIFT (PCG_ARRAYID_OFFSET * (PCG_ARRAYID_WIDTH != 0)) - -static inline void set_page_cgroup_array_id(struct page_cgroup *pc, - unsigned long id) -{ - pc->flags &= ~(PCG_ARRAYID_MASK << PCG_ARRAYID_SHIFT); - pc->flags |= (id & PCG_ARRAYID_MASK) << PCG_ARRAYID_SHIFT; -} - -static inline unsigned long page_cgroup_array_id(struct page_cgroup *pc) -{ - return (pc->flags >> PCG_ARRAYID_SHIFT) & PCG_ARRAYID_MASK; -} - #else /* CONFIG_CGROUP_MEM_RES_CTLR */ struct page_cgroup; diff -puN mm/page_cgroup.c~mm-memcg-remove-unused-node-section-info-from-pc-flags mm/page_cgroup.c --- a/mm/page_cgroup.c~mm-memcg-remove-unused-node-section-info-from-pc-flags +++ a/mm/page_cgroup.c @@ -11,12 +11,6 @@ #include <linux/swapops.h> #include <linux/kmemleak.h> -static void __meminit init_page_cgroup(struct page_cgroup *pc, unsigned long id) -{ - pc->flags = 0; - set_page_cgroup_array_id(pc, id); - pc->mem_cgroup = NULL; -} static unsigned long total_usage; #if !defined(CONFIG_SPARSEMEM) @@ -41,24 +35,11 @@ struct page_cgroup *lookup_page_cgroup(s return base + offset; } -struct page *lookup_cgroup_page(struct page_cgroup *pc) -{ - unsigned long pfn; - struct page *page; - pg_data_t *pgdat; - - pgdat = NODE_DATA(page_cgroup_array_id(pc)); - pfn = pc - pgdat->node_page_cgroup + pgdat->node_start_pfn; - page = pfn_to_page(pfn); - VM_BUG_ON(pc != lookup_page_cgroup(page)); - return page; -} - static int __init alloc_node_page_cgroup(int nid) { - struct page_cgroup *base, *pc; + struct page_cgroup *base; unsigned long table_size; - unsigned long start_pfn, nr_pages, index; + unsigned long nr_pages; start_pfn = NODE_DATA(nid)->node_start_pfn; nr_pages = NODE_DATA(nid)->node_spanned_pages; @@ -72,10 +53,6 @@ static int __init alloc_node_page_cgroup table_size, PAGE_SIZE, __pa(MAX_DMA_ADDRESS)); if (!base) return -ENOMEM; - for (index = 0; index < nr_pages; index++) { - pc = base + index; - init_page_cgroup(pc, nid); - } NODE_DATA(nid)->node_page_cgroup = base; total_usage += table_size; return 0; @@ -116,23 +93,10 @@ struct page_cgroup *lookup_page_cgroup(s return section->page_cgroup + pfn; } -struct page *lookup_cgroup_page(struct page_cgroup *pc) -{ - struct mem_section *section; - struct page *page; - unsigned long nr; - - nr = page_cgroup_array_id(pc); - section = __nr_to_section(nr); - page = pfn_to_page(pc - section->page_cgroup); - VM_BUG_ON(pc != lookup_page_cgroup(page)); - return page; -} - static void *__meminit alloc_page_cgroup(size_t size, int nid) { + gfp_t flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN; void *addr = NULL; - gfp_t flags = GFP_KERNEL | __GFP_NOWARN; addr = alloc_pages_exact_nid(nid, size, flags); if (addr) { @@ -141,9 +105,9 @@ static void *__meminit alloc_page_cgroup } if (node_state(nid, N_HIGH_MEMORY)) - addr = vmalloc_node(size, nid); + addr = vzalloc_node(size, nid); else - addr = vmalloc(size); + addr = vzalloc(size); return addr; } @@ -166,14 +130,11 @@ static void free_page_cgroup(void *addr) static int __meminit init_section_page_cgroup(unsigned long pfn, int nid) { - struct page_cgroup *base, *pc; struct mem_section *section; + struct page_cgroup *base; unsigned long table_size; - unsigned long nr; - int index; - nr = pfn_to_section_nr(pfn); - section = __nr_to_section(nr); + section = __pfn_to_section(pfn); if (section->page_cgroup) return 0; @@ -193,10 +154,6 @@ static int __meminit init_section_page_c return -ENOMEM; } - for (index = 0; index < PAGES_PER_SECTION; index++) { - pc = base + index; - init_page_cgroup(pc, nr); - } /* * The passed "pfn" may not be aligned to SECTION. For the calculation * we need to apply a mask. _ Subject: Subject: mm: memcg: remove unused node/section info from pc->flags Patches currently in -mm which might be from jweiner@xxxxxxxxxx are mm-add-extra-free-kbytes-tunable.patch mm-memcg-consolidate-hierarchy-iteration-primitives.patch mm-vmscan-distinguish-global-reclaim-from-global-lru-scanning.patch mm-vmscan-distinguish-between-memcg-triggering-reclaim-and-memcg-being-scanned.patch mm-memcg-per-priority-per-zone-hierarchy-scan-generations.patch mm-move-memcg-hierarchy-reclaim-to-generic-reclaim-code.patch mm-memcg-remove-optimization-of-keeping-the-root_mem_cgroup-lru-lists-empty.patch mm-vmscan-convert-global-reclaim-to-per-memcg-lru-lists.patch mm-collect-lru-list-heads-into-struct-lruvec.patch mm-make-per-memcg-lru-lists-exclusive.patch mm-memcg-remove-unused-node-section-info-from-pc-flags.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html