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authorDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp>2010-05-26 17:42:39 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-27 12:12:43 -0400
commit87946a72283be3de936adc754b7007df7d3e6aeb (patch)
tree0593c87ba36bae13d6a6d5dda65ebb41354954f8 /mm/shmem.c
parent90254a65833b67502d14736410b3857a15535c67 (diff)
memcg: move charge of file pages
This patch adds support for moving charge of file pages, which include normal file, tmpfs file and swaps of tmpfs file. It's enabled by setting bit 1 of <target cgroup>/memory.move_charge_at_immigrate. Unlike the case of anonymous pages, file pages(and swaps) in the range mmapped by the task will be moved even if the task hasn't done page fault, i.e. they might not be the task's "RSS", but other task's "RSS" that maps the same file. And mapcount of the page is ignored(the page can be moved even if page_mapcount(page) > 1). So, conditions that the page/swap should be met to be moved is that it must be in the range mmapped by the target task and it must be charged to the old cgroup. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix warning] Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/shmem.c')
-rw-r--r--mm/shmem.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/mm/shmem.c b/mm/shmem.c
index 4ef9797bd43..855eaf5b8d5 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2559,6 +2559,45 @@ out4:
2559 return error; 2559 return error;
2560} 2560}
2561 2561
2562#ifdef CONFIG_CGROUP_MEM_RES_CTLR
2563/**
2564 * mem_cgroup_get_shmem_target - find a page or entry assigned to the shmem file
2565 * @inode: the inode to be searched
2566 * @pgoff: the offset to be searched
2567 * @pagep: the pointer for the found page to be stored
2568 * @ent: the pointer for the found swap entry to be stored
2569 *
2570 * If a page is found, refcount of it is incremented. Callers should handle
2571 * these refcount.
2572 */
2573void mem_cgroup_get_shmem_target(struct inode *inode, pgoff_t pgoff,
2574 struct page **pagep, swp_entry_t *ent)
2575{
2576 swp_entry_t entry = { .val = 0 }, *ptr;
2577 struct page *page = NULL;
2578 struct shmem_inode_info *info = SHMEM_I(inode);
2579
2580 if ((pgoff << PAGE_CACHE_SHIFT) >= i_size_read(inode))
2581 goto out;
2582
2583 spin_lock(&info->lock);
2584 ptr = shmem_swp_entry(info, pgoff, NULL);
2585#ifdef CONFIG_SWAP
2586 if (ptr && ptr->val) {
2587 entry.val = ptr->val;
2588 page = find_get_page(&swapper_space, entry.val);
2589 } else
2590#endif
2591 page = find_get_page(inode->i_mapping, pgoff);
2592 if (ptr)
2593 shmem_swp_unmap(ptr);
2594 spin_unlock(&info->lock);
2595out:
2596 *pagep = page;
2597 *ent = entry;
2598}
2599#endif
2600
2562#else /* !CONFIG_SHMEM */ 2601#else /* !CONFIG_SHMEM */
2563 2602
2564/* 2603/*
@@ -2598,6 +2637,31 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user)
2598 return 0; 2637 return 0;
2599} 2638}
2600 2639
2640#ifdef CONFIG_CGROUP_MEM_RES_CTLR
2641/**
2642 * mem_cgroup_get_shmem_target - find a page or entry assigned to the shmem file
2643 * @inode: the inode to be searched
2644 * @pgoff: the offset to be searched
2645 * @pagep: the pointer for the found page to be stored
2646 * @ent: the pointer for the found swap entry to be stored
2647 *
2648 * If a page is found, refcount of it is incremented. Callers should handle
2649 * these refcount.
2650 */
2651void mem_cgroup_get_shmem_target(struct inode *inode, pgoff_t pgoff,
2652 struct page **pagep, swp_entry_t *ent)
2653{
2654 struct page *page = NULL;
2655
2656 if ((pgoff << PAGE_CACHE_SHIFT) >= i_size_read(inode))
2657 goto out;
2658 page = find_get_page(inode->i_mapping, pgoff);
2659out:
2660 *pagep = page;
2661 *ent = (swp_entry_t){ .val = 0 };
2662}
2663#endif
2664
2601#define shmem_vm_ops generic_file_vm_ops 2665#define shmem_vm_ops generic_file_vm_ops
2602#define shmem_file_operations ramfs_file_operations 2666#define shmem_file_operations ramfs_file_operations
2603#define shmem_get_inode(sb, dir, mode, dev, flags) ramfs_get_inode(sb, dir, mode, dev) 2667#define shmem_get_inode(sb, dir, mode, dev, flags) ramfs_get_inode(sb, dir, mode, dev)