Commit 7702bdbe authored by Jaegeuk Kim's avatar Jaegeuk Kim
Browse files

f2fs: avoid BG_GC in f2fs_balance_fs 



If many threads hit has_not_enough_free_secs() in f2fs_balance_fs() at the same
time, all the threads would do FG_GC or BG_GC.
In this critical path, we totally don't need to do BG_GC at all.
Let's avoid that.

Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent c040ff9d

fs/f2fs/f2fs.h

+1 −1
Original line number Diff line number Diff line
@@ -2183,7 +2183,7 @@ int f2fs_migrate_page(struct address_space *, struct page *, struct page *, 
int start_gc_thread(struct f2fs_sb_info *);

void stop_gc_thread(struct f2fs_sb_info *);

block_t start_bidx_of_node(unsigned int, struct inode *);

int f2fs_gc(struct f2fs_sb_info *, bool);

int f2fs_gc(struct f2fs_sb_info *, bool, bool);

void build_gc_manager(struct f2fs_sb_info *);



/*

fs/f2fs/file.c

+1 −1
Original line number Diff line number Diff line
@@ -1849,7 +1849,7 @@ static int f2fs_ioc_gc(struct file *filp, unsigned long arg) 
		mutex_lock(&sbi->gc_mutex);

	}



	ret = f2fs_gc(sbi, sync);

	ret = f2fs_gc(sbi, sync, true);

out:

	mnt_drop_write_file(filp);

	return ret;

fs/f2fs/gc.c

+5 −2
Original line number Diff line number Diff line
@@ -82,7 +82,7 @@ static int gc_thread_func(void *data) 
		stat_inc_bggc_count(sbi);



		/* if return value is not zero, no victim was selected */

		if (f2fs_gc(sbi, test_opt(sbi, FORCE_FG_GC)))

		if (f2fs_gc(sbi, test_opt(sbi, FORCE_FG_GC), true))

			wait_ms = gc_th->no_gc_sleep_time;



		trace_f2fs_background_gc(sbi->sb, wait_ms,
@@ -909,7 +909,7 @@ next: 
	return sec_freed;

}



int f2fs_gc(struct f2fs_sb_info *sbi, bool sync)

int f2fs_gc(struct f2fs_sb_info *sbi, bool sync, bool background)

{

	unsigned int segno;

	int gc_type = sync ? FG_GC : BG_GC;
@@ -950,6 +950,9 @@ gc_more: 
			if (ret)

				goto stop;

		}

	} else if (gc_type == BG_GC && !background) {

		/* f2fs_balance_fs doesn't need to do BG_GC in critical path. */

		goto stop;

	}



	if (segno == NULL_SEGNO && !__get_victim(sbi, &segno, gc_type))

fs/f2fs/segment.c

+1 −1
Original line number Diff line number Diff line
@@ -366,7 +366,7 @@ void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need) 
	 */

	if (has_not_enough_free_secs(sbi, 0, 0)) {

		mutex_lock(&sbi->gc_mutex);

		f2fs_gc(sbi, false);

		f2fs_gc(sbi, false, false);

	}

}

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