diff options
| -rw-r--r-- | fs/fs-writeback.c | 23 | ||||
| -rw-r--r-- | include/linux/writeback.h | 11 |
2 files changed, 21 insertions, 13 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 227ff12257f..50445cf0b83 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -30,15 +30,6 @@ #include "internal.h" /* - * The maximum number of pages to writeout in a single bdi flush/kupdate - * operation. We do this so we don't hold I_SYNC against an inode for - * enormous amounts of time, which would block a userspace task which has - * been forced to throttle against that inode. Also, the code reevaluates - * the dirty each time it has written this many pages. - */ -#define MAX_WRITEBACK_PAGES 1024L - -/* * Passed into wb_writeback(), essentially a subset of writeback_control */ struct wb_writeback_work { @@ -515,7 +506,8 @@ static bool pin_sb_for_writeback(struct super_block *sb) return false; } -static long writeback_chunk_size(struct wb_writeback_work *work) +static long writeback_chunk_size(struct backing_dev_info *bdi, + struct wb_writeback_work *work) { long pages; @@ -534,8 +526,13 @@ static long writeback_chunk_size(struct wb_writeback_work *work) */ if (work->sync_mode == WB_SYNC_ALL || work->tagged_writepages) pages = LONG_MAX; - else - pages = min(MAX_WRITEBACK_PAGES, work->nr_pages); + else { + pages = min(bdi->avg_write_bandwidth / 2, + global_dirty_limit / DIRTY_SCOPE); + pages = min(pages, work->nr_pages); + pages = round_down(pages + MIN_WRITEBACK_PAGES, + MIN_WRITEBACK_PAGES); + } return pages; } @@ -600,7 +597,7 @@ static long writeback_sb_inodes(struct super_block *sb, continue; } __iget(inode); - write_chunk = writeback_chunk_size(work); + write_chunk = writeback_chunk_size(wb->bdi, work); wbc.nr_to_write = write_chunk; wbc.pages_skipped = 0; diff --git a/include/linux/writeback.h b/include/linux/writeback.h index b625073b80c..f1bfa12ea24 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -8,6 +8,10 @@ #include <linux/fs.h> /* + * 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) @@ -25,9 +29,16 @@ * 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 +/* + * 4MB minimal write chunk size + */ +#define MIN_WRITEBACK_PAGES (4096UL >> (PAGE_CACHE_SHIFT - 10)) + struct backing_dev_info; /* |