From 6536e3123e5d3371a6f52e32a3d0694bcc987702 Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Fri, 20 Jan 2012 14:33:53 -0800 Subject: mm: fix warnings regarding enum migrate_mode sparc64 allmodconfig: In file included from include/linux/compat.h:15, from /usr/src/25/arch/sparc/include/asm/siginfo.h:19, from include/linux/signal.h:5, from include/linux/sched.h:73, from arch/sparc/kernel/asm-offsets.c:13: include/linux/fs.h:618: warning: parameter has incomplete type It seems that my sparc64 compiler (gcc-3.4.5) doesn't like the forward declaration of enums. Fix this by moving the "enum migrate_mode" definition into its own header file. Acked-by: Mel Gorman Cc: Rik van Riel Cc: Andrea Arcangeli Cc: Minchan Kim Cc: Dave Jones Cc: Jan Kara Cc: Andy Isaacson Cc: Nai Xia Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/fs.h | 2 +- include/linux/migrate.h | 14 +------------- include/linux/migrate_mode.h | 16 ++++++++++++++++ 3 files changed, 18 insertions(+), 14 deletions(-) create mode 100644 include/linux/migrate_mode.h (limited to 'include') diff --git a/include/linux/fs.h b/include/linux/fs.h index 0244082d42c..4b3a41fe22b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -10,6 +10,7 @@ #include #include #include +#include /* * It's silly to have NR_OPEN bigger than NR_FILE, but you can change @@ -526,7 +527,6 @@ enum positive_aop_returns { struct page; struct address_space; struct writeback_control; -enum migrate_mode; struct iov_iter { const struct iovec *iov; diff --git a/include/linux/migrate.h b/include/linux/migrate.h index eaf867412f7..05ed2828a55 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -3,22 +3,10 @@ #include #include +#include typedef struct page *new_page_t(struct page *, unsigned long private, int **); -/* - * MIGRATE_ASYNC means never block - * MIGRATE_SYNC_LIGHT in the current implementation means to allow blocking - * on most operations but not ->writepage as the potential stall time - * is too significant - * MIGRATE_SYNC will block when migrating pages - */ -enum migrate_mode { - MIGRATE_ASYNC, - MIGRATE_SYNC_LIGHT, - MIGRATE_SYNC, -}; - #ifdef CONFIG_MIGRATION #define PAGE_MIGRATION 1 diff --git a/include/linux/migrate_mode.h b/include/linux/migrate_mode.h new file mode 100644 index 00000000000..ebf3d89a391 --- /dev/null +++ b/include/linux/migrate_mode.h @@ -0,0 +1,16 @@ +#ifndef MIGRATE_MODE_H_INCLUDED +#define MIGRATE_MODE_H_INCLUDED +/* + * MIGRATE_ASYNC means never block + * MIGRATE_SYNC_LIGHT in the current implementation means to allow blocking + * on most operations but not ->writepage as the potential stall time + * is too significant + * MIGRATE_SYNC will block when migrating pages + */ +enum migrate_mode { + MIGRATE_ASYNC, + MIGRATE_SYNC_LIGHT, + MIGRATE_SYNC, +}; + +#endif /* MIGRATE_MODE_H_INCLUDED */ -- cgit v1.2.3-70-g09d2 From cb78edfdcef5259ac9e9088bd63810d21299928d Mon Sep 17 00:00:00 2001 From: Michael Holzheu Date: Fri, 20 Jan 2012 14:34:16 -0800 Subject: kdump: define KEXEC_NOTE_BYTES arch specific for s390x kdump only allocates memory for the prstatus ELF note. For s390x, besides of prstatus multiple ELF notes for various different register types are stored. Therefore the currently allocated memory is not sufficient. With this patch the KEXEC_NOTE_BYTES macro can be defined by architecture code and for s390x it is set to the correct size now. Signed-off-by: Michael Holzheu Cc: "Eric W. Biederman" Cc: Vivek Goyal Cc: Martin Schwidefsky Cc: Heiko Carstens Reviewed-by: Simon Horman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/include/asm/kexec.h | 18 ++++++++++++++++++ include/linux/kexec.h | 2 ++ 2 files changed, 20 insertions(+) (limited to 'include') diff --git a/arch/s390/include/asm/kexec.h b/arch/s390/include/asm/kexec.h index cf4e47b0948..3f30dac804e 100644 --- a/arch/s390/include/asm/kexec.h +++ b/arch/s390/include/asm/kexec.h @@ -42,6 +42,24 @@ /* The native architecture */ #define KEXEC_ARCH KEXEC_ARCH_S390 +/* + * Size for s390x ELF notes per CPU + * + * Seven notes plus zero note at the end: prstatus, fpregset, timer, + * tod_cmp, tod_reg, control regs, and prefix + */ +#define KEXEC_NOTE_BYTES \ + (ALIGN(sizeof(struct elf_note), 4) * 8 + \ + ALIGN(sizeof("CORE"), 4) * 7 + \ + ALIGN(sizeof(struct elf_prstatus), 4) + \ + ALIGN(sizeof(elf_fpregset_t), 4) + \ + ALIGN(sizeof(u64), 4) + \ + ALIGN(sizeof(u64), 4) + \ + ALIGN(sizeof(u32), 4) + \ + ALIGN(sizeof(u64) * 16, 4) + \ + ALIGN(sizeof(u32), 4) \ + ) + /* Provide a dummy definition to avoid build failures. */ static inline void crash_setup_regs(struct pt_regs *newregs, struct pt_regs *oldregs) { } diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 2fa0901219d..0d7d6a1b172 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -50,9 +50,11 @@ * note header. For kdump, the code in vmcore.c runs in the context * of the second kernel to combine them into one note. */ +#ifndef KEXEC_NOTE_BYTES #define KEXEC_NOTE_BYTES ( (KEXEC_NOTE_HEAD_BYTES * 2) + \ KEXEC_CORE_NOTE_NAME_BYTES + \ KEXEC_CORE_NOTE_DESC_BYTES ) +#endif /* * This structure is used to hold the arguments that are used when loading -- cgit v1.2.3-70-g09d2 From 245132643e1cfcd145bbc86a716c1818371fcb93 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Fri, 20 Jan 2012 14:34:21 -0800 Subject: SHM_UNLOCK: fix Unevictable pages stranded after swap Commit cc39c6a9bbde ("mm: account skipped entries to avoid looping in find_get_pages") correctly fixed an infinite loop; but left a problem that find_get_pages() on shmem would return 0 (appearing to callers to mean end of tree) when it meets a run of nr_pages swap entries. The only uses of find_get_pages() on shmem are via pagevec_lookup(), called from invalidate_mapping_pages(), and from shmctl SHM_UNLOCK's scan_mapping_unevictable_pages(). The first is already commented, and not worth worrying about; but the second can leave pages on the Unevictable list after an unusual sequence of swapping and locking. Fix that by using shmem_find_get_pages_and_swap() (then ignoring the swap) instead of pagevec_lookup(). But I don't want to contaminate vmscan.c with shmem internals, nor shmem.c with LRU locking. So move scan_mapping_unevictable_pages() into shmem.c, renaming it shmem_unlock_mapping(); and rename check_move_unevictable_page() to check_move_unevictable_pages(), looping down an array of pages, oftentimes under the same lock. Leave out the "rotate unevictable list" block: that's a leftover from when this was used for /proc/sys/vm/scan_unevictable_pages, whose flawed handling involved looking at pages at tail of LRU. Was there significance to the sequence first ClearPageUnevictable, then test page_evictable, then SetPageUnevictable here? I think not, we're under LRU lock, and have no barriers between those. Signed-off-by: Hugh Dickins Reviewed-by: KOSAKI Motohiro Cc: Minchan Kim Cc: Rik van Riel Cc: Shaohua Li Cc: Eric Dumazet Cc: Johannes Weiner Cc: Michel Lespinasse Cc: [back to 3.1 but will need respins] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/shmem_fs.h | 1 + include/linux/swap.h | 2 +- ipc/shm.c | 2 +- mm/shmem.c | 46 +++++++++++++++-- mm/vmscan.c | 128 +++++++++++++++-------------------------------- 5 files changed, 83 insertions(+), 96 deletions(-) (limited to 'include') diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index e4c711c6f32..79ab2555b3b 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -48,6 +48,7 @@ extern struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags); extern int shmem_zero_setup(struct vm_area_struct *); extern int shmem_lock(struct file *file, int lock, struct user_struct *user); +extern void shmem_unlock_mapping(struct address_space *mapping); extern struct page *shmem_read_mapping_page_gfp(struct address_space *mapping, pgoff_t index, gfp_t gfp_mask); extern void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end); diff --git a/include/linux/swap.h b/include/linux/swap.h index 06061a7f8e6..3e60228e729 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -273,7 +273,7 @@ static inline int zone_reclaim(struct zone *z, gfp_t mask, unsigned int order) #endif extern int page_evictable(struct page *page, struct vm_area_struct *vma); -extern void scan_mapping_unevictable_pages(struct address_space *); +extern void check_move_unevictable_pages(struct page **, int nr_pages); extern unsigned long scan_unevictable_pages; extern int scan_unevictable_handler(struct ctl_table *, int, diff --git a/ipc/shm.c b/ipc/shm.c index 854ab58e5f6..b76be5bda6c 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -916,7 +916,7 @@ SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf) shp->mlock_user = NULL; get_file(shm_file); shm_unlock(shp); - scan_mapping_unevictable_pages(shm_file->f_mapping); + shmem_unlock_mapping(shm_file->f_mapping); fput(shm_file); goto out; } diff --git a/mm/shmem.c b/mm/shmem.c index 4aaa53abe30..269d049294a 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -379,7 +379,7 @@ static int shmem_free_swap(struct address_space *mapping, /* * Pagevec may contain swap entries, so shuffle up pages before releasing. */ -static void shmem_pagevec_release(struct pagevec *pvec) +static void shmem_deswap_pagevec(struct pagevec *pvec) { int i, j; @@ -389,7 +389,36 @@ static void shmem_pagevec_release(struct pagevec *pvec) pvec->pages[j++] = page; } pvec->nr = j; - pagevec_release(pvec); +} + +/* + * SysV IPC SHM_UNLOCK restore Unevictable pages to their evictable lists. + */ +void shmem_unlock_mapping(struct address_space *mapping) +{ + struct pagevec pvec; + pgoff_t indices[PAGEVEC_SIZE]; + pgoff_t index = 0; + + pagevec_init(&pvec, 0); + /* + * Minor point, but we might as well stop if someone else SHM_LOCKs it. + */ + while (!mapping_unevictable(mapping)) { + /* + * Avoid pagevec_lookup(): find_get_pages() returns 0 as if it + * has finished, if it hits a row of PAGEVEC_SIZE swap entries. + */ + pvec.nr = shmem_find_get_pages_and_swap(mapping, index, + PAGEVEC_SIZE, pvec.pages, indices); + if (!pvec.nr) + break; + index = indices[pvec.nr - 1] + 1; + shmem_deswap_pagevec(&pvec); + check_move_unevictable_pages(pvec.pages, pvec.nr); + pagevec_release(&pvec); + cond_resched(); + } } /* @@ -440,7 +469,8 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend) } unlock_page(page); } - shmem_pagevec_release(&pvec); + shmem_deswap_pagevec(&pvec); + pagevec_release(&pvec); mem_cgroup_uncharge_end(); cond_resched(); index++; @@ -470,7 +500,8 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend) continue; } if (index == start && indices[0] > end) { - shmem_pagevec_release(&pvec); + shmem_deswap_pagevec(&pvec); + pagevec_release(&pvec); break; } mem_cgroup_uncharge_start(); @@ -494,7 +525,8 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend) } unlock_page(page); } - shmem_pagevec_release(&pvec); + shmem_deswap_pagevec(&pvec); + pagevec_release(&pvec); mem_cgroup_uncharge_end(); index++; } @@ -2438,6 +2470,10 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user) return 0; } +void shmem_unlock_mapping(struct address_space *mapping) +{ +} + void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend) { truncate_inode_pages_range(inode->i_mapping, lstart, lend); diff --git a/mm/vmscan.c b/mm/vmscan.c index e097c1026b5..c52b2355265 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -26,7 +26,6 @@ #include /* for try_to_release_page(), buffer_heads_over_limit */ #include -#include #include #include #include @@ -661,7 +660,7 @@ redo: * When racing with an mlock or AS_UNEVICTABLE clearing * (page is unlocked) make sure that if the other thread * does not observe our setting of PG_lru and fails - * isolation/check_move_unevictable_page, + * isolation/check_move_unevictable_pages, * we see PG_mlocked/AS_UNEVICTABLE cleared below and move * the page back to the evictable list. * @@ -3501,107 +3500,58 @@ int page_evictable(struct page *page, struct vm_area_struct *vma) #ifdef CONFIG_SHMEM /** - * check_move_unevictable_page - check page for evictability and move to appropriate zone lru list - * @page: page to check evictability and move to appropriate lru list - * @zone: zone page is in + * check_move_unevictable_pages - check pages for evictability and move to appropriate zone lru list + * @pages: array of pages to check + * @nr_pages: number of pages to check * - * Checks a page for evictability and moves the page to the appropriate - * zone lru list. - * - * Restrictions: zone->lru_lock must be held, page must be on LRU and must - * have PageUnevictable set. + * Checks pages for evictability and moves them to the appropriate lru list. * * This function is only used for SysV IPC SHM_UNLOCK. */ -static void check_move_unevictable_page(struct page *page, struct zone *zone) +void check_move_unevictable_pages(struct page **pages, int nr_pages) { struct lruvec *lruvec; + struct zone *zone = NULL; + int pgscanned = 0; + int pgrescued = 0; + int i; - VM_BUG_ON(PageActive(page)); -retry: - ClearPageUnevictable(page); - if (page_evictable(page, NULL)) { - enum lru_list l = page_lru_base_type(page); - - __dec_zone_state(zone, NR_UNEVICTABLE); - lruvec = mem_cgroup_lru_move_lists(zone, page, - LRU_UNEVICTABLE, l); - list_move(&page->lru, &lruvec->lists[l]); - __inc_zone_state(zone, NR_INACTIVE_ANON + l); - __count_vm_event(UNEVICTABLE_PGRESCUED); - } else { - /* - * rotate unevictable list - */ - SetPageUnevictable(page); - lruvec = mem_cgroup_lru_move_lists(zone, page, LRU_UNEVICTABLE, - LRU_UNEVICTABLE); - list_move(&page->lru, &lruvec->lists[LRU_UNEVICTABLE]); - if (page_evictable(page, NULL)) - goto retry; - } -} - -/** - * scan_mapping_unevictable_pages - scan an address space for evictable pages - * @mapping: struct address_space to scan for evictable pages - * - * Scan all pages in mapping. Check unevictable pages for - * evictability and move them to the appropriate zone lru list. - * - * This function is only used for SysV IPC SHM_UNLOCK. - */ -void scan_mapping_unevictable_pages(struct address_space *mapping) -{ - pgoff_t next = 0; - pgoff_t end = (i_size_read(mapping->host) + PAGE_CACHE_SIZE - 1) >> - PAGE_CACHE_SHIFT; - struct zone *zone; - struct pagevec pvec; - - if (mapping->nrpages == 0) - return; - - pagevec_init(&pvec, 0); - while (next < end && - pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { - int i; - int pg_scanned = 0; - - zone = NULL; - - for (i = 0; i < pagevec_count(&pvec); i++) { - struct page *page = pvec.pages[i]; - pgoff_t page_index = page->index; - struct zone *pagezone = page_zone(page); + for (i = 0; i < nr_pages; i++) { + struct page *page = pages[i]; + struct zone *pagezone; - pg_scanned++; - if (page_index > next) - next = page_index; - next++; + pgscanned++; + pagezone = page_zone(page); + if (pagezone != zone) { + if (zone) + spin_unlock_irq(&zone->lru_lock); + zone = pagezone; + spin_lock_irq(&zone->lru_lock); + } - if (pagezone != zone) { - if (zone) - spin_unlock_irq(&zone->lru_lock); - zone = pagezone; - spin_lock_irq(&zone->lru_lock); - } + if (!PageLRU(page) || !PageUnevictable(page)) + continue; - if (PageLRU(page) && PageUnevictable(page)) - check_move_unevictable_page(page, zone); + if (page_evictable(page, NULL)) { + enum lru_list lru = page_lru_base_type(page); + + VM_BUG_ON(PageActive(page)); + ClearPageUnevictable(page); + __dec_zone_state(zone, NR_UNEVICTABLE); + lruvec = mem_cgroup_lru_move_lists(zone, page, + LRU_UNEVICTABLE, lru); + list_move(&page->lru, &lruvec->lists[lru]); + __inc_zone_state(zone, NR_INACTIVE_ANON + lru); + pgrescued++; } - if (zone) - spin_unlock_irq(&zone->lru_lock); - pagevec_release(&pvec); + } - count_vm_events(UNEVICTABLE_PGSCANNED, pg_scanned); - cond_resched(); + if (zone) { + __count_vm_events(UNEVICTABLE_PGRESCUED, pgrescued); + __count_vm_events(UNEVICTABLE_PGSCANNED, pgscanned); + spin_unlock_irq(&zone->lru_lock); } } -#else -void scan_mapping_unevictable_pages(struct address_space *mapping) -{ -} #endif /* CONFIG_SHMEM */ static void warn_scan_unevictable_pages(void) -- cgit v1.2.3-70-g09d2