commit 274bd9ba39425610fdb9a6827602197a5cd27cd8
author Chao Yu <yuchao0@huawei.com> Sat Sep 29 18:31:28 2018 +0800
committer Jaegeuk Kim <jaegeuk@kernel.org> Sun Sep 30 18:33:34 2018 -0700
tree 9f0502bf4cbc4364a61a1553ec96c5bd0d767975
parent b63e7be5908cb757fc6b98fb9534dabd78b5338a

f2fs: add to account skip count of background GC

This patch adds to account skip count of background GC, and show stat
info via 'status' debugfs entry.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/gc.c

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index f541aa3..99ed8a5 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -40,13 +40,16 @@ static int gc_thread_func(void *data)
 		if (gc_th->gc_wake)
 			gc_th->gc_wake = 0;
 
-		if (try_to_freeze())
+		if (try_to_freeze()) {
+			stat_other_skip_bggc_count(sbi);
 			continue;
+		}
 		if (kthread_should_stop())
 			break;
 
 		if (sbi->sb->s_writers.frozen >= SB_FREEZE_WRITE) {
 			increase_sleep_time(gc_th, &wait_ms);
+			stat_other_skip_bggc_count(sbi);
 			continue;
 		}
 
@@ -55,8 +58,10 @@ static int gc_thread_func(void *data)
 			f2fs_stop_checkpoint(sbi, false);
 		}
 
-		if (!sb_start_write_trylock(sbi->sb))
+		if (!sb_start_write_trylock(sbi->sb)) {
+			stat_other_skip_bggc_count(sbi);
 			continue;
+		}
 
 		/*
 		 * [GC triggering condition]
@@ -77,12 +82,15 @@ static int gc_thread_func(void *data)
 			goto do_gc;
 		}
 
-		if (!mutex_trylock(&sbi->gc_mutex))
+		if (!mutex_trylock(&sbi->gc_mutex)) {
+			stat_other_skip_bggc_count(sbi);
 			goto next;
+		}
 
 		if (!is_idle(sbi, GC_TIME)) {
 			increase_sleep_time(gc_th, &wait_ms);
 			mutex_unlock(&sbi->gc_mutex);
+			stat_io_skip_bggc_count(sbi);
 			goto next;
 		}