f2fs: refactor f2fs_gc to call checkpoint in urgent condition

The major change is to call checkpoint, if there's not enough space while having
some prefree segments in FG_GC case.

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index c748cdfb0501b16334b4c30c90896ab82ec51a5b..ba5775dcade658f64c99ed4ef193a42e72320a77 100644 (file)
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -1829,7 +1829,10 @@ gc_more:
                goto stop;
        }
 
-       if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0, 0)) {
+       /* Let's run FG_GC, if we don't have enough space. */
+       if (has_not_enough_free_secs(sbi, 0, 0)) {
+               gc_type = FG_GC;
+
                /*
                 * For example, if there are many prefree_segments below given
                 * threshold, we can make them free by checkpoint. Then, we
@@ -1840,8 +1843,6 @@ gc_more:
                        if (ret)
                                goto stop;
                }
-               if (has_not_enough_free_secs(sbi, 0, 0))
-                       gc_type = FG_GC;
        }
 
        /* f2fs_balance_fs doesn't need to do BG_GC in critical path. */
@@ -1868,19 +1869,15 @@ retry:
        if (seg_freed == f2fs_usable_segs_in_sec(sbi, segno))
                sec_freed++;
 
-       if (gc_type == FG_GC)
+       if (gc_type == FG_GC) {
                sbi->cur_victim_sec = NULL_SEGNO;
 
-       if (gc_control->init_gc_type == FG_GC ||
-           !has_not_enough_free_secs(sbi,
-                               (gc_type == FG_GC) ? sec_freed : 0, 0)) {
-               if (gc_type == FG_GC && sec_freed < gc_control->nr_free_secs)
-                       goto go_gc_more;
-               goto stop;
-       }
-
-       /* FG_GC stops GC by skip_count */
-       if (gc_type == FG_GC) {
+               if (!has_not_enough_free_secs(sbi, sec_freed, 0)) {
+                       if (!gc_control->no_bg_gc &&
+                           sec_freed < gc_control->nr_free_secs)
+                               goto go_gc_more;
+                       goto stop;
+               }
                if (sbi->skipped_gc_rwsem)
                        skipped_round++;
                round++;
@@ -1889,6 +1886,8 @@ retry:
                        ret = f2fs_write_checkpoint(sbi, &cpc);
                        goto stop;
                }
+       } else if (!has_not_enough_free_secs(sbi, 0, 0)) {
+               goto stop;
        }
 
        __get_secs_required(sbi, NULL, &upper_secs, NULL);