[PATCH 1/8] writeback: propagate the various reasons for writeback

[Jens Axboe]

Avoid losing context by propagating the various reason why we
initiate writeback.

Signed-off-by: Jens Axboe <ax...@fb.com>
---
 fs/fs-writeback.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 5c46ed9f3e14..387610cf4f7f 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -52,6 +52,7 @@ struct wb_writeback_work {
        unsigned int range_cyclic:1;
        unsigned int for_background:1;
        unsigned int for_sync:1;        /* sync(2) WB_SYNC_ALL writeback */
+       unsigned int for_reclaim:1;     /* for mem reclaim */
        unsigned int auto_free:1;       /* free on completion */
        enum wb_reason reason;          /* why was writeback initiated? */
 
@@ -942,6 +943,21 @@ void wb_start_writeback(struct bdi_writeback *wb, long 
nr_pages,
        work->reason    = reason;
        work->auto_free = 1;
 
+       switch (reason) {
+       case WB_REASON_BACKGROUND:
+       case WB_REASON_PERIODIC:
+               work->for_background = 1;
+               break;
+       case WB_REASON_TRY_TO_FREE_PAGES:
+       case WB_REASON_FREE_MORE_MEM:
+               work->for_reclaim = 1;
+       case WB_REASON_SYNC:
+               work->for_sync = 1;
+               break;
+       default:
+               break;
+       }
+
        wb_queue_work(wb, work);
 }
 
@@ -1443,6 +1459,7 @@ static long writeback_sb_inodes(struct super_block *sb,
                .for_kupdate            = work->for_kupdate,
                .for_background         = work->for_background,
                .for_sync               = work->for_sync,
+               .for_reclaim            = work->for_reclaim,
                .range_cyclic           = work->range_cyclic,
                .range_start            = 0,
                .range_end              = LLONG_MAX,
-- 
2.4.1.168.g1ea28e1