[PATCH 02/16] FS-Cache: Recruit a couple of page flags for cache management [try #3]
Recruit a couple of page flags to aid in cache management. The following extra flags are defined: (1) PG_fscache (PG_owner_priv_2) The marked page is backed by a local cache and is pinning resources in the cache driver. (2) PG_fscache_write (PG_owner_priv_3) The marked page is being written to the local cache. The page may not be modified whilst this is in progress. If PG_fscache is set, then things that checked for PG_private will now also check for that. This includes things like truncation and page invalidation. The function page_has_private() had been added to detect this. Signed-off-by: David Howells <[EMAIL PROTECTED]> --- fs/splice.c|2 +- include/linux/page-flags.h | 30 +- include/linux/pagemap.h| 11 +++ mm/filemap.c | 16 mm/migrate.c |2 +- mm/page_alloc.c|3 +++ mm/readahead.c |9 + mm/swap.c |4 ++-- mm/swap_state.c|4 ++-- mm/truncate.c | 10 +- mm/vmscan.c|2 +- 11 files changed, 76 insertions(+), 17 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index c010a72..ae4f5b7 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -58,7 +58,7 @@ static int page_cache_pipe_buf_steal(struct pipe_inode_info *pipe, */ wait_on_page_writeback(page); - if (PagePrivate(page)) + if (page_has_private(page)) try_to_release_page(page, GFP_KERNEL); /* diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 209d3a4..eaf9854 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -83,19 +83,24 @@ #define PG_private 11 /* If pagecache, has fs-private data */ #define PG_writeback 12 /* Page is under writeback */ +#define PG_owner_priv_213 /* Owner use. If pagecache, fs may use */ #define PG_compound14 /* Part of a compound page */ #define PG_swapcache 15 /* Swap page: swp_entry_t in private */ #define PG_mappedtodisk16 /* Has blocks allocated on-disk */ #define PG_reclaim 17 /* To be reclaimed asap */ +#define PG_owner_priv_318 /* Owner use. If pagecache, fs may use */ #define PG_buddy 19 /* Page is free, on buddy lists */ /* PG_readahead is only used for file reads; PG_reclaim is only for writes */ #define PG_readahead PG_reclaim /* Reminder to do async read-ahead */ -/* PG_owner_priv_1 users should have descriptive aliases */ +/* PG_owner_priv_1/2/3 users should have descriptive aliases */ #define PG_checked PG_owner_priv_1 /* Used by some filesystems */ #define PG_pinned PG_owner_priv_1 /* Xen pinned pagetable */ +#define PG_fscache PG_owner_priv_2 /* Backed by local cache */ +#define PG_fscache_write PG_owner_priv_3 /* Writing to local cache */ + #if (BITS_PER_LONG > 32) /* @@ -199,6 +204,18 @@ static inline void SetPageUptodate(struct page *page) #define TestClearPageWriteback(page) test_and_clear_bit(PG_writeback, \ &(page)->flags) +#define PageFsCache(page) test_bit(PG_fscache, &(page)->flags) +#define SetPageFsCache(page) set_bit(PG_fscache, &(page)->flags) +#define ClearPageFsCache(page) clear_bit(PG_fscache, &(page)->flags) +#define TestSetPageFsCache(page) test_and_set_bit(PG_fscache, &(page)->flags) +#define TestClearPageFsCache(page) test_and_clear_bit(PG_fscache, &(page)->flags) + +#define PageFsCacheWrite(page) test_bit(PG_fscache_write, &(page)->flags) +#define SetPageFsCacheWrite(page) set_bit(PG_fscache_write, &(page)->flags) +#define ClearPageFsCacheWrite(page)clear_bit(PG_fscache_write, &(page)->flags) +#define TestSetPageFsCacheWrite(page) test_and_set_bit(PG_fscache_write, &(page)->flags) +#define TestClearPageFsCacheWrite(page) test_and_clear_bit(PG_fscache_write, &(page)->flags) + #define PageBuddy(page)test_bit(PG_buddy, &(page)->flags) #define __SetPageBuddy(page) __set_bit(PG_buddy, &(page)->flags) #define __ClearPageBuddy(page) __clear_bit(PG_buddy, &(page)->flags) @@ -272,4 +289,15 @@ static inline void set_page_writeback(struct page *page) test_set_page_writeback(page); } +/** + * page_has_private - Determine if page has private stuff + * @page: The page to be checked + * + * Determine if a page has private stuff, indicating that release routines + * should be invoked upon it. + */ +#define page_has_private(page) \ + ((page)->flags & ((1 << PG_private) | \ + (1 << PG_fscache))) + #endif /* PAGE_FLAGS_H */ diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
[PATCH 02/16] FS-Cache: Recruit a couple of page flags for cache management [try #3]
Recruit a couple of page flags to aid in cache management. The following extra flags are defined: (1) PG_fscache (PG_owner_priv_2) The marked page is backed by a local cache and is pinning resources in the cache driver. (2) PG_fscache_write (PG_owner_priv_3) The marked page is being written to the local cache. The page may not be modified whilst this is in progress. If PG_fscache is set, then things that checked for PG_private will now also check for that. This includes things like truncation and page invalidation. The function page_has_private() had been added to detect this. Signed-off-by: David Howells [EMAIL PROTECTED] --- fs/splice.c|2 +- include/linux/page-flags.h | 30 +- include/linux/pagemap.h| 11 +++ mm/filemap.c | 16 mm/migrate.c |2 +- mm/page_alloc.c|3 +++ mm/readahead.c |9 + mm/swap.c |4 ++-- mm/swap_state.c|4 ++-- mm/truncate.c | 10 +- mm/vmscan.c|2 +- 11 files changed, 76 insertions(+), 17 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index c010a72..ae4f5b7 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -58,7 +58,7 @@ static int page_cache_pipe_buf_steal(struct pipe_inode_info *pipe, */ wait_on_page_writeback(page); - if (PagePrivate(page)) + if (page_has_private(page)) try_to_release_page(page, GFP_KERNEL); /* diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 209d3a4..eaf9854 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -83,19 +83,24 @@ #define PG_private 11 /* If pagecache, has fs-private data */ #define PG_writeback 12 /* Page is under writeback */ +#define PG_owner_priv_213 /* Owner use. If pagecache, fs may use */ #define PG_compound14 /* Part of a compound page */ #define PG_swapcache 15 /* Swap page: swp_entry_t in private */ #define PG_mappedtodisk16 /* Has blocks allocated on-disk */ #define PG_reclaim 17 /* To be reclaimed asap */ +#define PG_owner_priv_318 /* Owner use. If pagecache, fs may use */ #define PG_buddy 19 /* Page is free, on buddy lists */ /* PG_readahead is only used for file reads; PG_reclaim is only for writes */ #define PG_readahead PG_reclaim /* Reminder to do async read-ahead */ -/* PG_owner_priv_1 users should have descriptive aliases */ +/* PG_owner_priv_1/2/3 users should have descriptive aliases */ #define PG_checked PG_owner_priv_1 /* Used by some filesystems */ #define PG_pinned PG_owner_priv_1 /* Xen pinned pagetable */ +#define PG_fscache PG_owner_priv_2 /* Backed by local cache */ +#define PG_fscache_write PG_owner_priv_3 /* Writing to local cache */ + #if (BITS_PER_LONG 32) /* @@ -199,6 +204,18 @@ static inline void SetPageUptodate(struct page *page) #define TestClearPageWriteback(page) test_and_clear_bit(PG_writeback, \ (page)-flags) +#define PageFsCache(page) test_bit(PG_fscache, (page)-flags) +#define SetPageFsCache(page) set_bit(PG_fscache, (page)-flags) +#define ClearPageFsCache(page) clear_bit(PG_fscache, (page)-flags) +#define TestSetPageFsCache(page) test_and_set_bit(PG_fscache, (page)-flags) +#define TestClearPageFsCache(page) test_and_clear_bit(PG_fscache, (page)-flags) + +#define PageFsCacheWrite(page) test_bit(PG_fscache_write, (page)-flags) +#define SetPageFsCacheWrite(page) set_bit(PG_fscache_write, (page)-flags) +#define ClearPageFsCacheWrite(page)clear_bit(PG_fscache_write, (page)-flags) +#define TestSetPageFsCacheWrite(page) test_and_set_bit(PG_fscache_write, (page)-flags) +#define TestClearPageFsCacheWrite(page) test_and_clear_bit(PG_fscache_write, (page)-flags) + #define PageBuddy(page)test_bit(PG_buddy, (page)-flags) #define __SetPageBuddy(page) __set_bit(PG_buddy, (page)-flags) #define __ClearPageBuddy(page) __clear_bit(PG_buddy, (page)-flags) @@ -272,4 +289,15 @@ static inline void set_page_writeback(struct page *page) test_set_page_writeback(page); } +/** + * page_has_private - Determine if page has private stuff + * @page: The page to be checked + * + * Determine if a page has private stuff, indicating that release routines + * should be invoked upon it. + */ +#define page_has_private(page) \ + ((page)-flags ((1 PG_private) | \ + (1 PG_fscache))) + #endif /* PAGE_FLAGS_H */ diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 8a83537..d1049b6 100644 ---
