diff options
Diffstat (limited to 'include/linux/writeback.h')
| -rw-r--r-- | include/linux/writeback.h | 55 |
1 files changed, 43 insertions, 12 deletions
diff --git a/include/linux/writeback.h b/include/linux/writeback.h index 17e7ccc322a..f1bfa12ea24 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -7,9 +7,39 @@ #include <linux/sched.h> #include <linux/fs.h> -struct backing_dev_info; +/* + * The 1/4 region under the global dirty thresh is for smooth dirty throttling: + * + * (thresh - thresh/DIRTY_FULL_SCOPE, thresh) + * + * The 1/16 region above the global dirty limit will be put to maximum pauses: + * + * (limit, limit + limit/DIRTY_MAXPAUSE_AREA) + * + * The 1/16 region above the max-pause region, dirty exceeded bdi's will be put + * to loops: + * + * (limit + limit/DIRTY_MAXPAUSE_AREA, limit + limit/DIRTY_PASSGOOD_AREA) + * + * Further beyond, all dirtier tasks will enter a loop waiting (possibly long + * time) for the dirty pages to drop, unless written enough pages. + * + * The global dirty threshold is normally equal to the global dirty limit, + * except when the system suddenly allocates a lot of anonymous memory and + * knocks down the global dirty threshold quickly, in which case the global + * dirty limit will follow down slowly to prevent livelocking all dirtier tasks. + */ +#define DIRTY_SCOPE 8 +#define DIRTY_FULL_SCOPE (DIRTY_SCOPE / 2) +#define DIRTY_MAXPAUSE_AREA 16 +#define DIRTY_PASSGOOD_AREA 8 -extern spinlock_t inode_wb_list_lock; +/* + * 4MB minimal write chunk size + */ +#define MIN_WRITEBACK_PAGES (4096UL >> (PAGE_CACHE_SHIFT - 10)) + +struct backing_dev_info; /* * fs/fs-writeback.c @@ -26,11 +56,6 @@ enum writeback_sync_modes { */ struct writeback_control { enum writeback_sync_modes sync_mode; - unsigned long *older_than_this; /* If !NULL, only write back inodes - older than this */ - unsigned long wb_start; /* Time writeback_inodes_wb was - called. This is needed to avoid - extra jobs and livelock */ long nr_to_write; /* Write this many pages, and decrement this for each page written */ long pages_skipped; /* Pages which were not written */ @@ -43,13 +68,11 @@ struct writeback_control { loff_t range_start; loff_t range_end; - unsigned nonblocking:1; /* Don't get stuck on request queues */ - unsigned encountered_congestion:1; /* An output: a queue is full */ unsigned for_kupdate:1; /* A kupdate writeback */ unsigned for_background:1; /* A background writeback */ + unsigned tagged_writepages:1; /* tag-and-write to avoid livelock */ unsigned for_reclaim:1; /* Invoked from the page allocator */ unsigned range_cyclic:1; /* range_start is cyclic */ - unsigned more_io:1; /* more io to be dispatched */ }; /* @@ -62,8 +85,7 @@ void writeback_inodes_sb_nr(struct super_block *, unsigned long nr); int writeback_inodes_sb_if_idle(struct super_block *); int writeback_inodes_sb_nr_if_idle(struct super_block *, unsigned long nr); void sync_inodes_sb(struct super_block *); -void writeback_inodes_wb(struct bdi_writeback *wb, - struct writeback_control *wbc); +long writeback_inodes_wb(struct bdi_writeback *wb, long nr_pages); long wb_do_writeback(struct bdi_writeback *wb, int force_wait); void wakeup_flusher_threads(long nr_pages); @@ -94,6 +116,8 @@ static inline void laptop_sync_completion(void) { } #endif void throttle_vm_writeout(gfp_t gfp_mask); +extern unsigned long global_dirty_limit; + /* These are exported to sysctl. */ extern int dirty_background_ratio; extern unsigned long dirty_background_bytes; @@ -128,6 +152,13 @@ void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty); unsigned long bdi_dirty_limit(struct backing_dev_info *bdi, unsigned long dirty); +void __bdi_update_bandwidth(struct backing_dev_info *bdi, + unsigned long thresh, + unsigned long dirty, + unsigned long bdi_thresh, + unsigned long bdi_dirty, + unsigned long start_time); + void page_writeback_init(void); void balance_dirty_pages_ratelimited_nr(struct address_space *mapping, unsigned long nr_pages_dirtied); |