f2fs: let discard thread wait a little longer if dev is busy

This patch modify discard thread wait policy as below:
	issued       io_interrupted     wait time(ms)
1.        8                 0               50
2.      (0,8)               1               50
3.        0                 1              500 (dev is busy)
4.        0                 0            60000 (no candidates)

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Yunlei He 2018-04-08 15:11:11 +08:00 committed by Jaegeuk Kim
parent 2ef79ecb5e
commit f9d1dced75
2 changed files with 7 additions and 1 deletions

View File

@ -180,6 +180,7 @@ enum {
#define DEF_MAX_DISCARD_REQUEST 8 /* issue 8 discards per round */
#define DEF_MAX_DISCARD_LEN 512 /* Max. 2MB per discard */
#define DEF_MIN_DISCARD_ISSUE_TIME 50 /* 50 ms, if exists */
#define DEF_MID_DISCARD_ISSUE_TIME 500 /* 500 ms, if device busy */
#define DEF_MAX_DISCARD_ISSUE_TIME 60000 /* 60 s, if no candidates */
#define DEF_DISCARD_URGENT_UTIL 80 /* do more discard over 80% */
#define DEF_CP_INTERVAL 60 /* 60 secs */
@ -282,6 +283,7 @@ enum {
struct discard_policy {
int type; /* type of discard */
unsigned int min_interval; /* used for candidates exist */
unsigned int mid_interval; /* used for device busy */
unsigned int max_interval; /* used for candidates not exist */
unsigned int max_requests; /* # of discards issued per round */
unsigned int io_aware_gran; /* minimum granularity discard not be aware of I/O */

View File

@ -937,6 +937,7 @@ static void __init_discard_policy(struct f2fs_sb_info *sbi,
if (discard_type == DPOLICY_BG) {
dpolicy->min_interval = DEF_MIN_DISCARD_ISSUE_TIME;
dpolicy->mid_interval = DEF_MID_DISCARD_ISSUE_TIME;
dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME;
dpolicy->io_aware = true;
dpolicy->sync = false;
@ -946,6 +947,7 @@ static void __init_discard_policy(struct f2fs_sb_info *sbi,
}
} else if (discard_type == DPOLICY_FORCE) {
dpolicy->min_interval = DEF_MIN_DISCARD_ISSUE_TIME;
dpolicy->mid_interval = DEF_MID_DISCARD_ISSUE_TIME;
dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME;
dpolicy->io_aware = false;
} else if (discard_type == DPOLICY_FSTRIM) {
@ -1420,9 +1422,11 @@ static int issue_discard_thread(void *data)
sb_start_intwrite(sbi->sb);
issued = __issue_discard_cmd(sbi, &dpolicy);
if (issued) {
if (issued > 0) {
__wait_all_discard_cmd(sbi, &dpolicy);
wait_ms = dpolicy.min_interval;
} else if (issued == -1){
wait_ms = dpolicy.mid_interval;
} else {
wait_ms = dpolicy.max_interval;
}