[PATCH] f2fs: continuous counting for 'issued' in __issue_discard_cmd_orderly()

From: Yuwei Guan
Date: Mon Nov 21 2022 - 11:11:45 EST


As the 'dcc->discard_granularity' and 'dcc->max_ordered_discard' can be set
at the user space, and if the 'dcc->max_ordered_discard' is set larger than
'dcc->discard_granularity' in DPOLICY_BG mode, or it's a volume device,
discard_granularity can be tuned to 1 in f2fs_tuning_parameters(),
it will may send more requests than the number of 'dpolicy->max_requests'
in issue_discard_thread().

This patch will fix the issue.

Signed-off-by: Yuwei Guan <Yuwei.Guan@xxxxxxxxxxxxx>
---
fs/f2fs/segment.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 8b0b76550578..b0157bf392fb 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -1379,8 +1379,8 @@ static int __queue_discard_cmd(struct f2fs_sb_info *sbi,
return 0;
}

-static unsigned int __issue_discard_cmd_orderly(struct f2fs_sb_info *sbi,
- struct discard_policy *dpolicy)
+static int __issue_discard_cmd_orderly(struct f2fs_sb_info *sbi,
+ struct discard_policy *dpolicy, int *issued)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
struct discard_cmd *prev_dc = NULL, *next_dc = NULL;
@@ -1388,7 +1388,6 @@ static unsigned int __issue_discard_cmd_orderly(struct f2fs_sb_info *sbi,
struct discard_cmd *dc;
struct blk_plug plug;
unsigned int pos = dcc->next_pos;
- unsigned int issued = 0;
bool io_interrupted = false;

mutex_lock(&dcc->cmd_lock);
@@ -1415,9 +1414,9 @@ static unsigned int __issue_discard_cmd_orderly(struct f2fs_sb_info *sbi,
}

dcc->next_pos = dc->lstart + dc->len;
- err = __submit_discard_cmd(sbi, dpolicy, dc, &issued);
+ err = __submit_discard_cmd(sbi, dpolicy, dc, issued);

- if (issued >= dpolicy->max_requests)
+ if (*issued >= dpolicy->max_requests)
break;
next:
node = rb_next(&dc->rb_node);
@@ -1433,10 +1432,10 @@ static unsigned int __issue_discard_cmd_orderly(struct f2fs_sb_info *sbi,

mutex_unlock(&dcc->cmd_lock);

- if (!issued && io_interrupted)
- issued = -1;
+ if (!(*issued) && io_interrupted)
+ *issued = -1;

- return issued;
+ return *issued;
}
static unsigned int __wait_all_discard_cmd(struct f2fs_sb_info *sbi,
struct discard_policy *dpolicy);
@@ -1465,7 +1464,7 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi,
break;

if (i + 1 < dcc->max_ordered_discard && dpolicy->ordered)
- return __issue_discard_cmd_orderly(sbi, dpolicy);
+ return __issue_discard_cmd_orderly(sbi, dpolicy, &issued);

pend_list = &dcc->pend_list[i];

--
2.34.1