[PATCH v2 6/6] f2fs: give up CP_TRIMMED_FLAG if it drops discards

From: Chao Yu
Date: Tue Oct 03 2017 - 21:08:59 EST


From: Chao Yu <yuchao0@xxxxxxxxxx>

In ->umount, once we drop remained discard entries, we should not
set CP_TRIMMED_FLAG with another checkpoint.

Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
v2:
- rebase on last codes of Jaegeuk's dev-test branch.
fs/f2fs/f2fs.h | 2 +-
fs/f2fs/segment.c | 15 +++++++++++----
fs/f2fs/super.c | 5 +++--
3 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index f274805e231d..c85f49c41003 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2565,7 +2565,7 @@ void init_discard_policy(struct discard_policy *dpolicy, int discard_type,
unsigned int granularity);
void refresh_sit_entry(struct f2fs_sb_info *sbi, block_t old, block_t new);
void stop_discard_thread(struct f2fs_sb_info *sbi);
-void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi);
+bool f2fs_wait_discard_bios(struct f2fs_sb_info *sbi);
void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc);
void release_discard_addrs(struct f2fs_sb_info *sbi);
int npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra);
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 4a108321233d..bfbcff8339c5 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -1196,12 +1196,13 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi,
return issued;
}

-static void __drop_discard_cmd(struct f2fs_sb_info *sbi)
+static bool __drop_discard_cmd(struct f2fs_sb_info *sbi)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
struct list_head *pend_list;
struct discard_cmd *dc, *tmp;
int i;
+ bool dropped = false;

mutex_lock(&dcc->cmd_lock);
for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
@@ -1209,9 +1210,12 @@ static void __drop_discard_cmd(struct f2fs_sb_info *sbi)
list_for_each_entry_safe(dc, tmp, pend_list, list) {
f2fs_bug_on(sbi, dc->state != D_PREP);
__remove_discard_cmd(sbi, dc);
+ dropped = true;
}
}
mutex_unlock(&dcc->cmd_lock);
+
+ return dropped;
}

static void __wait_one_discard_bio(struct f2fs_sb_info *sbi,
@@ -1306,15 +1310,18 @@ void stop_discard_thread(struct f2fs_sb_info *sbi)
}

/* This comes from f2fs_put_super */
-void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi)
+bool f2fs_wait_discard_bios(struct f2fs_sb_info *sbi)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
struct discard_policy dpolicy;
+ bool dropped;

init_discard_policy(&dpolicy, DPOLICY_UMOUNT, dcc->discard_granularity);
__issue_discard_cmd(sbi, &dpolicy);
- __drop_discard_cmd(sbi);
+ dropped = __drop_discard_cmd(sbi);
__wait_all_discard_cmd(sbi, &dpolicy);
+
+ return dropped;
}

static int issue_discard_thread(void *data)
@@ -1659,7 +1666,7 @@ void init_discard_policy(struct discard_policy *dpolicy,
dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME;
dpolicy->max_requests = DEF_MAX_DISCARD_REQUEST;
dpolicy->io_aware_gran = MAX_PLIST_NUM;
- dpolicy->io_aware = false;
+ dpolicy->io_aware = true;
} else if (discard_type == DPOLICY_FSTRIM) {
dpolicy->max_requests = DEF_MAX_DISCARD_REQUEST;
dpolicy->io_aware_gran = MAX_PLIST_NUM;
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index a13269d1a1f0..1d68c18a487b 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -807,6 +807,7 @@ static void f2fs_put_super(struct super_block *sb)
{
struct f2fs_sb_info *sbi = F2FS_SB(sb);
int i;
+ bool dropped;

f2fs_quota_off_umount(sb);

@@ -827,9 +828,9 @@ static void f2fs_put_super(struct super_block *sb)
}

/* be sure to wait for any on-going discard commands */
- f2fs_wait_discard_bios(sbi, true);
+ dropped = f2fs_wait_discard_bios(sbi);

- if (f2fs_discard_en(sbi) && !sbi->discard_blks) {
+ if (f2fs_discard_en(sbi) && !sbi->discard_blks && !dropped) {
struct cp_control cpc = {
.reason = CP_UMOUNT | CP_TRIMMED,
};
--
2.14.1.145.gb3622a4ee