Re: [PATCH v2] f2fs: introduce DEFAULT_IO_TIMEOUT
From: Chao Yu
Date: Thu Feb 20 2020 - 01:26:37 EST
Hi Jaegeuk,
Could you help to adapt this change for f2fs_wait_on_all_pages() manually
in your tree?
- io_schedule_timeout(HZ/50);
+ io_schedule_timeout(DEFAULT_IO_TIMEOUT);
Thanks,
On 2020/2/17 17:45, Chao Yu wrote:
> 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@xxxxxxxxxx>
> ---
> v2:
> - use msecs_to_jiffies(20) instead.
> fs/f2fs/compress.c | 3 ++-
> fs/f2fs/data.c | 4 ++--
> fs/f2fs/f2fs.h | 3 +++
> fs/f2fs/gc.c | 3 ++-
> fs/f2fs/inode.c | 2 +-
> fs/f2fs/node.c | 2 +-
> fs/f2fs/recovery.c | 5 +++--
> fs/f2fs/segment.c | 10 ++++++----
> fs/f2fs/super.c | 6 ++++--
> 9 files changed, 24 insertions(+), 14 deletions(-)
>
> diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
> index 0282149aa4c8..b9ea531ffbb6 100644
> --- a/fs/f2fs/compress.c
> +++ b/fs/f2fs/compress.c
> @@ -985,7 +985,8 @@ static int f2fs_write_raw_pages(struct compress_ctx *cc,
> } 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;
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index 019c91f7b301..a877cc50a4c3 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -2332,7 +2332,7 @@ int f2fs_encrypt_one_page(struct f2fs_io_info *fio)
> /* 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;
> }
> @@ -2923,7 +2923,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
> if (wbc->sync_mode == WB_SYNC_ALL) {
> cond_resched();
> congestion_wait(BLK_RW_ASYNC,
> - HZ/50);
> + DEFAULT_IO_TIMEOUT);
> goto retry_write;
> }
> goto next;
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 816a5adb83a4..72c91a6dd549 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -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
>
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index 897de003e423..3db11d5a50d5 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -974,7 +974,8 @@ static int move_data_page(struct inode *inode, block_t bidx, int gc_type,
> 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)
> diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
> index 78c3f1d70f1d..156cc5ef3044 100644
> --- a/fs/f2fs/inode.c
> +++ b/fs/f2fs/inode.c
> @@ -518,7 +518,7 @@ struct inode *f2fs_iget_retry(struct super_block *sb, unsigned long ino)
> 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;
> }
> }
> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> index 9824f055a5bc..d5edbe2ce4a1 100644
> --- a/fs/f2fs/node.c
> +++ b/fs/f2fs/node.c
> @@ -2602,7 +2602,7 @@ 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;
> }
>
> diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c
> index 348e8d463b3e..dd804c07eeb0 100644
> --- a/fs/f2fs/recovery.c
> +++ b/fs/f2fs/recovery.c
> @@ -534,7 +534,7 @@ static int do_recover_data(struct f2fs_sb_info *sbi, struct inode *inode,
> 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 @@ static int do_recover_data(struct f2fs_sb_info *sbi, struct inode *inode,
> 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;
> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> index c3252603ff79..1628bc8327f1 100644
> --- a/fs/f2fs/segment.c
> +++ b/fs/f2fs/segment.c
> @@ -245,7 +245,8 @@ static int __revoke_inmem_pages(struct inode *inode,
> 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 @@ void f2fs_drop_inmem_pages_all(struct f2fs_sb_info *sbi, bool gc_failure)
> 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 @@ static int __f2fs_commit_inmem_pages(struct inode *inode)
> 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 @@ static unsigned int __issue_discard_cmd_range(struct f2fs_sb_info *sbi,
> 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:
> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> index 1456979222cf..dcfa5836767c 100644
> --- a/fs/f2fs/super.c
> +++ b/fs/f2fs/super.c
> @@ -1884,7 +1884,8 @@ static ssize_t f2fs_quota_read(struct super_block *sb, int type, char *data,
> 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);
> @@ -1938,7 +1939,8 @@ static ssize_t f2fs_quota_write(struct super_block *sb, int type,
> &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);
>