From: Jaegeuk Kim <jaegeuk@kernel.org>
Date: Fri, 14 Dec 2018 04:50:51 +0000 (-0800)
Subject: f2fs: flush stale issued discard candidates
X-Git-Tag: rel_imx_5.10.35_2.0.0-somdevices.0~5618^2~10
X-Git-Url: https://git.somdevices.com/?a=commitdiff_plain;h=76c7bfb3a89371aa87bda99c8ee2611ff5150434;p=linux.git

f2fs: flush stale issued discard candidates

Sometimes, I could observe # of issuing_discard to be 1 which blocks background
jobs due to is_idle()=false.
The only way to get out of it was to trigger gc_urgent. This patch avoids that
by checking any candidates as done in the list.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 0f7a92be678a..d9a3345a244a 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -1652,6 +1652,10 @@ static int issue_discard_thread(void *data)
 		if (dcc->discard_wake)
 			dcc->discard_wake = 0;
 
+		/* clean up pending candidates before going to sleep */
+		if (atomic_read(&dcc->queued_discard))
+			__wait_all_discard_cmd(sbi, NULL);
+
 		if (try_to_freeze())
 			continue;
 		if (f2fs_readonly(sbi->sb))