[PATCH] f2fs: speed up gc_urgent mode with SSR and more discard commands

[Jaegeuk Kim]

From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>

This patch activates SSR and issuing more discard commands in gc_urgent mode.

Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---
 fs/f2fs/f2fs.h    |  1 +
 fs/f2fs/segment.c | 19 ++++++++++++++++++-
 fs/f2fs/segment.h | 13 -------------
 3 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 7a467fcd4bcd..3fbf55e41694 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2517,6 +2517,7 @@ void destroy_node_manager_caches(void);
 /*
  * segment.c
  */
+bool need_SSR(struct f2fs_sb_info *sbi);
 void register_inmem_page(struct inode *inode, struct page *page);
 void drop_inmem_pages(struct inode *inode);
 void drop_inmem_page(struct inode *inode, struct page *page);
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 9e708e525ba8..d6e0c160a268 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -168,6 +168,21 @@ static unsigned long __find_rev_next_zero_bit(const unsigned long *addr,
 	return result - size + __reverse_ffz(tmp);
 }
 
+bool need_SSR(struct f2fs_sb_info *sbi)
+{
+	int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES);
+	int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS);
+	int imeta_secs = get_blocktype_secs(sbi, F2FS_DIRTY_IMETA);
+
+	if (test_opt(sbi, LFS))
+		return false;
+	if (sbi->gc_thread && sbi->gc_thread->gc_urgent)
+		return true;
+
+	return free_sections(sbi) <= (node_secs + 2 * dent_secs + imeta_secs +
+						2 * reserved_sections(sbi));
+}
+
 void register_inmem_page(struct inode *inode, struct page *page)
 {
 	struct f2fs_inode_info *fi = F2FS_I(inode);
@@ -1203,6 +1218,7 @@ static int issue_discard_thread(void *data)
 	wait_queue_head_t *q = &dcc->discard_wait_queue;
 	unsigned int wait_ms = DEF_MIN_DISCARD_ISSUE_TIME;
 	int issued;
+	bool urgent = false;
 
 	set_freezable();
 
@@ -1218,13 +1234,14 @@ static int issue_discard_thread(void *data)
 
 		if (dcc->discard_wake) {
 			dcc->discard_wake = 0;
+			urgent = sbi->gc_thread && sbi->gc_thread->gc_urgent;
 			if (sbi->gc_thread && sbi->gc_thread->gc_urgent)
 				mark_discard_range_all(sbi);
 		}
 
 		sb_start_intwrite(sbi->sb);
 
-		issued = __issue_discard_cmd(sbi, true);
+		issued = __issue_discard_cmd(sbi, !urgent);
 		if (issued) {
 			__wait_discard_cmd(sbi, true);
 			wait_ms = DEF_MIN_DISCARD_ISSUE_TIME;
diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 613b2fa7b1c1..e0a6cc23ace3 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -497,19 +497,6 @@ static inline int reserved_sections(struct f2fs_sb_info *sbi)
 	return GET_SEC_FROM_SEG(sbi, (unsigned int)reserved_segments(sbi));
 }
 
-static inline bool need_SSR(struct f2fs_sb_info *sbi)
-{
-	int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES);
-	int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS);
-	int imeta_secs = get_blocktype_secs(sbi, F2FS_DIRTY_IMETA);
-
-	if (test_opt(sbi, LFS))
-		return false;
-
-	return free_sections(sbi) <= (node_secs + 2 * dent_secs + imeta_secs +
-						2 * reserved_sections(sbi));
-}
-
 static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi,
 					int freed, int needed)
 {
-- 
2.14.0.rc1.383.gd1ce394fe2-goog