From 947e9762a8ddefda38aa21e249e6a4fec215cd12 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 22 May 2015 18:23:32 -0400 Subject: writeback: update wb_over_bg_thresh() to use wb_domain aware operations wb_over_bg_thresh() currently uses global_dirty_limits() and wb_dirty_limit() both of which are wrappers around operations which take dirty_throttle_control. For cgroup writeback support, the function will be updated to also consider memcg wb_domains which requires the context information carried in dirty_throttle_control. This patch updates wb_over_bg_thresh() so that it uses the underlying wb_domain aware operations directly and builds the global dirty_throttle_control in the process. This patch doesn't introduce any behavioral changes. Signed-off-by: Tejun Heo Cc: Jens Axboe Cc: Jan Kara Cc: Wu Fengguang Cc: Greg Thelen Signed-off-by: Jens Axboe --- mm/page-writeback.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) (limited to 'mm') diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 9d9a896fa7b5..a7ba5cee950b 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -1749,15 +1749,22 @@ EXPORT_SYMBOL(balance_dirty_pages_ratelimited); */ bool wb_over_bg_thresh(struct bdi_writeback *wb) { - unsigned long background_thresh, dirty_thresh; + struct dirty_throttle_control gdtc_stor = { GDTC_INIT(wb) }; + struct dirty_throttle_control * const gdtc = &gdtc_stor; - global_dirty_limits(&background_thresh, &dirty_thresh); + /* + * Similar to balance_dirty_pages() but ignores pages being written + * as we're trying to decide whether to put more under writeback. + */ + gdtc->avail = global_dirtyable_memory(); + gdtc->dirty = global_page_state(NR_FILE_DIRTY) + + global_page_state(NR_UNSTABLE_NFS); + domain_dirty_limits(gdtc); - if (global_page_state(NR_FILE_DIRTY) + - global_page_state(NR_UNSTABLE_NFS) > background_thresh) + if (gdtc->dirty > gdtc->bg_thresh) return true; - if (wb_stat(wb, WB_RECLAIMABLE) > wb_calc_thresh(wb, background_thresh)) + if (wb_stat(wb, WB_RECLAIMABLE) > __wb_calc_thresh(gdtc)) return true; return false; -- cgit v1.2.3