f2fs: introduce DEFAULT_IO_TIMEOUT

As Geert Uytterhoeven reported:

for parameter HZ/50 in congestion_wait(BLK_RW_ASYNC, HZ/50);

On some platforms, HZ can be less than 50, then unexpected 0 timeout
jiffies will be set in congestion_wait().

This patch introduces a macro DEFAULT_IO_TIMEOUT to wrap a determinate
value with msecs_to_jiffies(20) to instead HZ/50 to avoid such issue.

Quoted from Geert Uytterhoeven:

"A timeout of HZ means 1 second.
HZ/50 means 20 ms, but has the risk of being zero, if HZ < 50.

If you want to use a timeout of 20 ms, you best use msecs_to_jiffies(20),
as that takes care of the special cases, and never returns 0."

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Chao Yu 2020-02-17 17:45:44 +08:00 committed by Jaegeuk Kim
parent 2bac07635d
commit 5df7731f60
10 changed files with 25 additions and 15 deletions

View File

@ -1260,7 +1260,7 @@ void f2fs_wait_on_all_pages(struct f2fs_sb_info *sbi, int type)
if (unlikely(f2fs_cp_error(sbi)))
break;
io_schedule_timeout(HZ/50);
io_schedule_timeout(DEFAULT_IO_TIMEOUT);
}
finish_wait(&sbi->cp_wait, &wait);
}

View File

@ -988,7 +988,8 @@ retry_write:
} else if (ret == -EAGAIN) {
ret = 0;
cond_resched();
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC,
DEFAULT_IO_TIMEOUT);
lock_page(cc->rpages[i]);
clear_page_dirty_for_io(cc->rpages[i]);
goto retry_write;

View File

@ -2317,7 +2317,7 @@ retry_encrypt:
/* flush pending IOs and wait for a while in the ENOMEM case */
if (PTR_ERR(fio->encrypted_page) == -ENOMEM) {
f2fs_flush_merged_writes(fio->sbi);
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC, DEFAULT_IO_TIMEOUT);
gfp_flags |= __GFP_NOFAIL;
goto retry_encrypt;
}
@ -2908,7 +2908,7 @@ result:
if (wbc->sync_mode == WB_SYNC_ALL) {
cond_resched();
congestion_wait(BLK_RW_ASYNC,
HZ/50);
DEFAULT_IO_TIMEOUT);
goto retry_write;
}
goto next;

View File

@ -558,6 +558,9 @@ enum {
#define DEFAULT_RETRY_IO_COUNT 8 /* maximum retry read IO count */
/* congestion wait timeout value, default: 20ms */
#define DEFAULT_IO_TIMEOUT (msecs_to_jiffies(20))
/* maximum retry quota flush count */
#define DEFAULT_RETRY_QUOTA_FLUSH_COUNT 8

View File

@ -977,7 +977,8 @@ retry:
if (err) {
clear_cold_data(page);
if (err == -ENOMEM) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC,
DEFAULT_IO_TIMEOUT);
goto retry;
}
if (is_dirty)

View File

@ -535,7 +535,7 @@ retry:
inode = f2fs_iget(sb, ino);
if (IS_ERR(inode)) {
if (PTR_ERR(inode) == -ENOMEM) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC, DEFAULT_IO_TIMEOUT);
goto retry;
}
}

View File

@ -2599,7 +2599,7 @@ int f2fs_recover_inode_page(struct f2fs_sb_info *sbi, struct page *page)
retry:
ipage = f2fs_grab_cache_page(NODE_MAPPING(sbi), ino, false);
if (!ipage) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC, DEFAULT_IO_TIMEOUT);
goto retry;
}

View File

@ -534,7 +534,7 @@ retry_dn:
err = f2fs_get_dnode_of_data(&dn, start, ALLOC_NODE);
if (err) {
if (err == -ENOMEM) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC, DEFAULT_IO_TIMEOUT);
goto retry_dn;
}
goto out;
@ -617,7 +617,8 @@ retry_prev:
err = check_index_in_prev_nodes(sbi, dest, &dn);
if (err) {
if (err == -ENOMEM) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC,
DEFAULT_IO_TIMEOUT);
goto retry_prev;
}
goto err;

View File

@ -245,7 +245,8 @@ retry:
LOOKUP_NODE);
if (err) {
if (err == -ENOMEM) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC,
DEFAULT_IO_TIMEOUT);
cond_resched();
goto retry;
}
@ -312,7 +313,7 @@ next:
skip:
iput(inode);
}
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC, DEFAULT_IO_TIMEOUT);
cond_resched();
if (gc_failure) {
if (++looped >= count)
@ -415,7 +416,8 @@ retry:
err = f2fs_do_write_data_page(&fio);
if (err) {
if (err == -ENOMEM) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC,
DEFAULT_IO_TIMEOUT);
cond_resched();
goto retry;
}
@ -2801,7 +2803,7 @@ next:
blk_finish_plug(&plug);
mutex_unlock(&dcc->cmd_lock);
trimmed += __wait_all_discard_cmd(sbi, NULL);
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC, DEFAULT_IO_TIMEOUT);
goto next;
}
skip:

View File

@ -1885,7 +1885,8 @@ repeat:
page = read_cache_page_gfp(mapping, blkidx, GFP_NOFS);
if (IS_ERR(page)) {
if (PTR_ERR(page) == -ENOMEM) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC,
DEFAULT_IO_TIMEOUT);
goto repeat;
}
set_sbi_flag(F2FS_SB(sb), SBI_QUOTA_NEED_REPAIR);
@ -1939,7 +1940,8 @@ retry:
&page, NULL);
if (unlikely(err)) {
if (err == -ENOMEM) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
congestion_wait(BLK_RW_ASYNC,
DEFAULT_IO_TIMEOUT);
goto retry;
}
set_sbi_flag(F2FS_SB(sb), SBI_QUOTA_NEED_REPAIR);