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Message-ID: <36c2974c-8a4a-4da0-b497-aef4c9647f94@kernel.org>
Date: Mon, 15 Apr 2024 22:01:45 +0800
From: Chao Yu <chao@...nel.org>
To: Jaegeuk Kim <jaegeuk@...nel.org>
Cc: linux-kernel@...r.kernel.org, linux-f2fs-devel@...ts.sourceforge.net
Subject: Re: [f2fs-dev] [PATCH v3] f2fs: zone: don't block IO if there is
remained open zone
On 2024/4/15 11:26, Chao Yu wrote:
> On 2024/4/14 23:19, Jaegeuk Kim wrote:
>> It seems this caused kernel hang. Chao, have you tested this patch enough?
>
> Jaegeuk,
>
> Oh, I've checked this patch w/ fsstress before submitting it, but missed
> the SPO testcase... do you encounter kernel hang w/ SPO testcase?
I did see any hang issue w/ por_fsstress testcase, which testcase do you use?
Thanks,
>
> Anyway, let me test it more.
>
> Thanks,
>
>>
>> On 04/13, Chao Yu wrote:
>>> On 2024/4/13 5:11, Jaegeuk Kim wrote:
>>>> On 04/07, Chao Yu wrote:
>>>>> max open zone may be larger than log header number of f2fs, for
>>>>> such case, it doesn't need to wait last IO in previous zone, let's
>>>>> introduce available_open_zone semaphore, and reduce it once we
>>>>> submit first write IO in a zone, and increase it after completion
>>>>> of last IO in the zone.
>>>>>
>>>>> Cc: Daeho Jeong <daeho43@...il.com>
>>>>> Signed-off-by: Chao Yu <chao@...nel.org>
>>>>> ---
>>>>> v3:
>>>>> - avoid race condition in between __submit_merged_bio()
>>>>> and __allocate_new_segment().
>>>>> fs/f2fs/data.c | 105 ++++++++++++++++++++++++++++++----------------
>>>>> fs/f2fs/f2fs.h | 34 ++++++++++++---
>>>>> fs/f2fs/iostat.c | 7 ++++
>>>>> fs/f2fs/iostat.h | 2 +
>>>>> fs/f2fs/segment.c | 43 ++++++++++++++++---
>>>>> fs/f2fs/segment.h | 12 +++++-
>>>>> fs/f2fs/super.c | 2 +
>>>>> 7 files changed, 156 insertions(+), 49 deletions(-)
>>>>>
>>>>> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
>>>>> index 0d88649c60a5..18a4ac0a06bc 100644
>>>>> --- a/fs/f2fs/data.c
>>>>> +++ b/fs/f2fs/data.c
>>>>> @@ -373,11 +373,10 @@ static void f2fs_write_end_io(struct bio *bio)
>>>>> #ifdef CONFIG_BLK_DEV_ZONED
>>>>> static void f2fs_zone_write_end_io(struct bio *bio)
>>>>> {
>>>>> - struct f2fs_bio_info *io = (struct f2fs_bio_info *)bio->bi_private;
>>>>> + struct f2fs_sb_info *sbi = iostat_get_bio_private(bio);
>>>>> - bio->bi_private = io->bi_private;
>>>>> - complete(&io->zone_wait);
>>>>> f2fs_write_end_io(bio);
>>>>> + up(&sbi->available_open_zones);
>>>>> }
>>>>> #endif
>>>>> @@ -531,6 +530,24 @@ static void __submit_merged_bio(struct f2fs_bio_info *io)
>>>>> if (!io->bio)
>>>>> return;
>>>>> +#ifdef CONFIG_BLK_DEV_ZONED
>>>>> + if (io->open_zone) {
>>>>> + /*
>>>>> + * if there is no open zone, it will wait for last IO in
>>>>> + * previous zone before submitting new IO.
>>>>> + */
>>>>> + down(&fio->sbi->available_open_zones);
>>>>> + io->open_zone = false;
>>>>> + io->zone_openned = true;
>>>>> + }
>>>>> +
>>>>> + if (io->close_zone) {
>>>>> + io->bio->bi_end_io = f2fs_zone_write_end_io;
>>>>> + io->zone_openned = false;
>>>>> + io->close_zone = false;
>>>>> + }
>>>>> +#endif
>>>>> +
>>>>> if (is_read_io(fio->op)) {
>>>>> trace_f2fs_prepare_read_bio(io->sbi->sb, fio->type, io->bio);
>>>>> f2fs_submit_read_bio(io->sbi, io->bio, fio->type);
>>>>> @@ -601,9 +618,9 @@ int f2fs_init_write_merge_io(struct f2fs_sb_info *sbi)
>>>>> INIT_LIST_HEAD(&sbi->write_io[i][j].bio_list);
>>>>> init_f2fs_rwsem(&sbi->write_io[i][j].bio_list_lock);
>>>>> #ifdef CONFIG_BLK_DEV_ZONED
>>>>> - init_completion(&sbi->write_io[i][j].zone_wait);
>>>>> - sbi->write_io[i][j].zone_pending_bio = NULL;
>>>>> - sbi->write_io[i][j].bi_private = NULL;
>>>>> + sbi->write_io[i][j].open_zone = false;
>>>>> + sbi->write_io[i][j].zone_openned = false;
>>>>> + sbi->write_io[i][j].close_zone = false;
>>>>> #endif
>>>>> }
>>>>> }
>>>>> @@ -634,6 +651,31 @@ static void __f2fs_submit_merged_write(struct f2fs_sb_info *sbi,
>>>>> f2fs_up_write(&io->io_rwsem);
>>>>> }
>>>>> +void f2fs_blkzoned_submit_merged_write(struct f2fs_sb_info *sbi, int type)
>>>>> +{
>>>>> +#ifdef CONFIG_BLK_DEV_ZONED
>>>>> + struct f2fs_bio_info *io;
>>>>> +
>>>>> + if (!f2fs_sb_has_blkzoned(sbi))
>>>>> + return;
>>>>> +
>>>>> + io = sbi->write_io[PAGE_TYPE(type)] + type_to_temp(type);
>>>>> +
>>>>> + f2fs_down_write(&io->io_rwsem);
>>>>> + if (io->zone_openned) {
>>>>> + if (io->bio) {
>>>>> + io->close_zone = true;
>>>>> + __submit_merged_bio(io);
>>>>> + } else if (io->zone_openned) {
>>>>> + up(&sbi->available_open_zones);
>>>>> + io->zone_openned = false;
>>>>> + }
>>>>> + }
>>>>> + f2fs_up_write(&io->io_rwsem);
>>>>> +#endif
>>>>> +
>>>>> +}
>>>>> +
>>>>> static void __submit_merged_write_cond(struct f2fs_sb_info *sbi,
>>>>> struct inode *inode, struct page *page,
>>>>> nid_t ino, enum page_type type, bool force)
>>>>> @@ -918,22 +960,16 @@ int f2fs_merge_page_bio(struct f2fs_io_info *fio)
>>>>> }
>>>>> #ifdef CONFIG_BLK_DEV_ZONED
>>>>> -static bool is_end_zone_blkaddr(struct f2fs_sb_info *sbi, block_t blkaddr)
>>>>> +static bool is_blkaddr_zone_boundary(struct f2fs_sb_info *sbi,
>>>>> + block_t blkaddr, bool start)
>>>>> {
>>>>> - int devi = 0;
>>>>> + if (!f2fs_blkaddr_in_seqzone(sbi, blkaddr))
>>>>> + return false;
>>>>> +
>>>>> + if (start)
>>>>> + return (blkaddr % sbi->blocks_per_blkz) == 0;
>>>>> + return (blkaddr % sbi->blocks_per_blkz == sbi->blocks_per_blkz - 1);
>>>>> - if (f2fs_is_multi_device(sbi)) {
>>>>> - devi = f2fs_target_device_index(sbi, blkaddr);
>>>>> - if (blkaddr < FDEV(devi).start_blk ||
>>>>> - blkaddr > FDEV(devi).end_blk) {
>>>>> - f2fs_err(sbi, "Invalid block %x", blkaddr);
>>>>> - return false;
>>>>> - }
>>>>> - blkaddr -= FDEV(devi).start_blk;
>>>>> - }
>>>>> - return bdev_is_zoned(FDEV(devi).bdev) &&
>>>>> - f2fs_blkz_is_seq(sbi, devi, blkaddr) &&
>>>>> - (blkaddr % sbi->blocks_per_blkz == sbi->blocks_per_blkz - 1);
>>>>> }
>>>>> #endif
>>>>> @@ -944,20 +980,14 @@ void f2fs_submit_page_write(struct f2fs_io_info *fio)
>>>>> struct f2fs_bio_info *io = sbi->write_io[btype] + fio->temp;
>>>>> struct page *bio_page;
>>>>> enum count_type type;
>>>>> +#ifdef CONFIG_BLK_DEV_ZONED
>>>>> + bool blkzoned = f2fs_sb_has_blkzoned(sbi) && btype < META;
>>>>> +#endif
>>>>> f2fs_bug_on(sbi, is_read_io(fio->op));
>>>>> f2fs_down_write(&io->io_rwsem);
>>>>> next:
>>>>> -#ifdef CONFIG_BLK_DEV_ZONED
>>>>> - if (f2fs_sb_has_blkzoned(sbi) && btype < META && io->zone_pending_bio) {
>>>>> - wait_for_completion_io(&io->zone_wait);
>>>>> - bio_put(io->zone_pending_bio);
>>>>> - io->zone_pending_bio = NULL;
>>>>> - io->bi_private = NULL;
>>>>> - }
>>>>> -#endif
>>>>> -
>>>>> if (fio->in_list) {
>>>>> spin_lock(&io->io_lock);
>>>>> if (list_empty(&io->io_list)) {
>>>>> @@ -985,6 +1015,11 @@ void f2fs_submit_page_write(struct f2fs_io_info *fio)
>>>>> type = WB_DATA_TYPE(bio_page, fio->compressed_page);
>>>>> inc_page_count(sbi, type);
>>>>> +#ifdef CONFIG_BLK_DEV_ZONED
>>>>> + if (blkzoned && is_blkaddr_zone_boundary(sbi, fio->new_blkaddr, true))
>>>>> + io->open_zone = true;
>>>>> +#endif
>>>>> +
>>>>> if (io->bio &&
>>>>> (!io_is_mergeable(sbi, io->bio, io, fio, io->last_block_in_bio,
>>>>> fio->new_blkaddr) ||
>>>>> @@ -1010,15 +1045,11 @@ void f2fs_submit_page_write(struct f2fs_io_info *fio)
>>>>> io->last_block_in_bio = fio->new_blkaddr;
>>>>> trace_f2fs_submit_page_write(fio->page, fio);
>>>>> +
>>>>> #ifdef CONFIG_BLK_DEV_ZONED
>>>>> - if (f2fs_sb_has_blkzoned(sbi) && btype < META &&
>>>>> - is_end_zone_blkaddr(sbi, fio->new_blkaddr)) {
>>>>> - bio_get(io->bio);
>>>>> - reinit_completion(&io->zone_wait);
>>>>> - io->bi_private = io->bio->bi_private;
>>>>> - io->bio->bi_private = io;
>>>>> - io->bio->bi_end_io = f2fs_zone_write_end_io;
>>>>> - io->zone_pending_bio = io->bio;
>>>>> + if (blkzoned &&
>>>>> + is_blkaddr_zone_boundary(sbi, fio->new_blkaddr, false)) {
>>>>> + io->close_zone = true;
>>>>> __submit_merged_bio(io);
>>>>> }
>>>>> #endif
>>>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>>>>> index 694f8a52cb84..8a26530cf4fb 100644
>>>>> --- a/fs/f2fs/f2fs.h
>>>>> +++ b/fs/f2fs/f2fs.h
>>>>> @@ -1234,16 +1234,16 @@ struct f2fs_bio_info {
>>>>> struct bio *bio; /* bios to merge */
>>>>> sector_t last_block_in_bio; /* last block number */
>>>>> struct f2fs_io_info fio; /* store buffered io info. */
>>>>> -#ifdef CONFIG_BLK_DEV_ZONED
>>>>> - struct completion zone_wait; /* condition value for the previous open zone to close */
>>>>> - struct bio *zone_pending_bio; /* pending bio for the previous zone */
>>>>> - void *bi_private; /* previous bi_private for pending bio */
>>>>> -#endif
>>>>> struct f2fs_rwsem io_rwsem; /* blocking op for bio */
>>>>> spinlock_t io_lock; /* serialize DATA/NODE IOs */
>>>>> struct list_head io_list; /* track fios */
>>>>> struct list_head bio_list; /* bio entry list head */
>>>>> struct f2fs_rwsem bio_list_lock; /* lock to protect bio entry list */
>>>>> +#ifdef CONFIG_BLK_DEV_ZONED
>>>>> + bool open_zone; /* open a zone */
>>>>> + bool zone_openned; /* zone has been openned */
>>>>> + bool close_zone; /* close a zone */
>>>>> +#endif
>>>>> };
>>>>> #define FDEV(i) (sbi->devs[i])
>>>>> @@ -1560,6 +1560,7 @@ struct f2fs_sb_info {
>>>>> #ifdef CONFIG_BLK_DEV_ZONED
>>>>> unsigned int blocks_per_blkz; /* F2FS blocks per zone */
>>>>> unsigned int max_open_zones; /* max open zone resources of the zoned device */
>>>>> + struct semaphore available_open_zones; /* available open zones */
>>>>> #endif
>>>>> /* for node-related operations */
>>>>> @@ -3822,6 +3823,7 @@ void f2fs_destroy_bio_entry_cache(void);
>>>>> void f2fs_submit_read_bio(struct f2fs_sb_info *sbi, struct bio *bio,
>>>>> enum page_type type);
>>>>> int f2fs_init_write_merge_io(struct f2fs_sb_info *sbi);
>>>>> +void f2fs_blkzoned_submit_merged_write(struct f2fs_sb_info *sbi, int type);
>>>>> void f2fs_submit_merged_write(struct f2fs_sb_info *sbi, enum page_type type);
>>>>> void f2fs_submit_merged_write_cond(struct f2fs_sb_info *sbi,
>>>>> struct inode *inode, struct page *page,
>>>>> @@ -4469,6 +4471,28 @@ static inline bool f2fs_blkz_is_seq(struct f2fs_sb_info *sbi, int devi,
>>>>> return test_bit(zno, FDEV(devi).blkz_seq);
>>>>> }
>>>>> +
>>>>> +static inline bool f2fs_blkaddr_in_seqzone(struct f2fs_sb_info *sbi,
>>>>> + block_t blkaddr)
>>>>> +{
>>>>> + int devi = 0;
>>>>> +
>>>>> + if (f2fs_is_multi_device(sbi)) {
>>>>> + devi = f2fs_target_device_index(sbi, blkaddr);
>>>>> + if (blkaddr < FDEV(devi).start_blk ||
>>>>> + blkaddr > FDEV(devi).end_blk) {
>>>>> + f2fs_err(sbi, "Invalid block %x", blkaddr);
>>>>> + return false;
>>>>> + }
>>>>> + blkaddr -= FDEV(devi).start_blk;
>>>>> + }
>>>>> +
>>>>> + if (!bdev_is_zoned(FDEV(devi).bdev) ||
>>>>> + !f2fs_blkz_is_seq(sbi, devi, blkaddr))
>>>>> + return false;
>>>>> +
>>>>> + return true;
>>>>
>>>> Applied as below.
>>>>
>>>> @@ -4485,11 +4485,8 @@ static inline bool f2fs_blkaddr_in_seqzone(struct f2fs_sb_info *sbi,
>>>> blkaddr -= FDEV(devi).start_blk;
>>>> }
>>>>
>>>> - if (!bdev_is_zoned(FDEV(devi).bdev) ||
>>>> - !f2fs_blkz_is_seq(sbi, devi, blkaddr))
>>>> - return false;
>>>> -
>>>> - return true;
>>>> + return bdev_is_zoned(FDEV(devi).bdev) &&
>>>> + f2fs_blkz_is_seq(sbi, devi, blkaddr);
>>>
>>> Looks good, thank you for cleanup.
>>>
>>> Thanks,
>>>
>>>> }
>>>> #endif
>>>>
>>>>> +}
>>>>> #endif
>>>>> static inline int f2fs_bdev_index(struct f2fs_sb_info *sbi,
>>>>> diff --git a/fs/f2fs/iostat.c b/fs/f2fs/iostat.c
>>>>> index f8703038e1d8..a8626e297876 100644
>>>>> --- a/fs/f2fs/iostat.c
>>>>> +++ b/fs/f2fs/iostat.c
>>>>> @@ -237,6 +237,13 @@ static inline void __update_iostat_latency(struct bio_iostat_ctx *iostat_ctx,
>>>>> spin_unlock_irqrestore(&sbi->iostat_lat_lock, flags);
>>>>> }
>>>>> +void *iostat_get_bio_private(struct bio *bio)
>>>>> +{
>>>>> + struct bio_iostat_ctx *iostat_ctx = bio->bi_private;
>>>>> +
>>>>> + return iostat_ctx->sbi;
>>>>> +}
>>>>> +
>>>>> void iostat_update_and_unbind_ctx(struct bio *bio)
>>>>> {
>>>>> struct bio_iostat_ctx *iostat_ctx = bio->bi_private;
>>>>> diff --git a/fs/f2fs/iostat.h b/fs/f2fs/iostat.h
>>>>> index eb99d05cf272..9006c3d41590 100644
>>>>> --- a/fs/f2fs/iostat.h
>>>>> +++ b/fs/f2fs/iostat.h
>>>>> @@ -58,6 +58,7 @@ static inline struct bio_post_read_ctx *get_post_read_ctx(struct bio *bio)
>>>>> return iostat_ctx->post_read_ctx;
>>>>> }
>>>>> +extern void *iostat_get_bio_private(struct bio *bio);
>>>>> extern void iostat_update_and_unbind_ctx(struct bio *bio);
>>>>> extern void iostat_alloc_and_bind_ctx(struct f2fs_sb_info *sbi,
>>>>> struct bio *bio, struct bio_post_read_ctx *ctx);
>>>>> @@ -68,6 +69,7 @@ extern void f2fs_destroy_iostat(struct f2fs_sb_info *sbi);
>>>>> #else
>>>>> static inline void f2fs_update_iostat(struct f2fs_sb_info *sbi, struct inode *inode,
>>>>> enum iostat_type type, unsigned long long io_bytes) {}
>>>>> +static inline void *iostat_get_bio_private(struct bio *bio) { return bio->bi_private; }
>>>>> static inline void iostat_update_and_unbind_ctx(struct bio *bio) {}
>>>>> static inline void iostat_alloc_and_bind_ctx(struct f2fs_sb_info *sbi,
>>>>> struct bio *bio, struct bio_post_read_ctx *ctx) {}
>>>>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>>>>> index 4fd76e867e0a..4a3cf2888faf 100644
>>>>> --- a/fs/f2fs/segment.c
>>>>> +++ b/fs/f2fs/segment.c
>>>>> @@ -3140,6 +3140,9 @@ static int __allocate_new_segment(struct f2fs_sb_info *sbi, int type,
>>>>> return err;
>>>>> stat_inc_seg_type(sbi, curseg);
>>>>> locate_dirty_segment(sbi, old_segno);
>>>>> +
>>>>> + f2fs_blkzoned_submit_merged_write(sbi, type);
>>>>> +
>>>>> return 0;
>>>>> }
>>>>> @@ -3461,12 +3464,7 @@ static int __get_segment_type(struct f2fs_io_info *fio)
>>>>> f2fs_bug_on(fio->sbi, true);
>>>>> }
>>>>> - if (IS_HOT(type))
>>>>> - fio->temp = HOT;
>>>>> - else if (IS_WARM(type))
>>>>> - fio->temp = WARM;
>>>>> - else
>>>>> - fio->temp = COLD;
>>>>> + fio->temp = type_to_temp(type);
>>>>> return type;
>>>>> }
>>>>> @@ -4132,6 +4130,27 @@ static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
>>>>> return -EINVAL;
>>>>> }
>>>>> +#ifdef CONFIG_BLK_DEV_ZONED
>>>>> + if (f2fs_sb_has_blkzoned(sbi)) {
>>>>> + for (type = 0; type < NR_PERSISTENT_LOG; type++) {
>>>>> + struct curseg_info *curseg = CURSEG_I(sbi, type);
>>>>> + enum page_type ptype;
>>>>> + enum temp_type temp;
>>>>> +
>>>>> + if (!(curseg->next_blkoff % sbi->blocks_per_blkz))
>>>>> + continue;
>>>>> +
>>>>> + if (!f2fs_blkaddr_in_seqzone(sbi,
>>>>> + START_BLOCK(sbi, curseg->segno)))
>>>>> + continue;
>>>>> +
>>>>> + ptype = PAGE_TYPE(type);
>>>>> + temp = type_to_temp(type);
>>>>> + down(&sbi->available_open_zones);
>>>>> + sbi->write_io[ptype][temp].zone_openned = true;
>>>>> + }
>>>>> + }
>>>>> +#endif
>>>>> return 0;
>>>>> }
>>>>> @@ -5451,6 +5470,18 @@ static void destroy_curseg(struct f2fs_sb_info *sbi)
>>>>> for (i = 0; i < NR_CURSEG_TYPE; i++) {
>>>>> kfree(array[i].sum_blk);
>>>>> kfree(array[i].journal);
>>>>> +
>>>>> +#ifdef CONFIG_BLK_DEV_ZONED
>>>>> + if (f2fs_sb_has_blkzoned(sbi)) {
>>>>> + enum page_type ptype = PAGE_TYPE(i);
>>>>> + enum temp_type temp = type_to_temp(i);
>>>>> +
>>>>> + if (sbi->write_io[ptype][temp].zone_openned) {
>>>>> + up(&sbi->available_open_zones);
>>>>> + sbi->write_io[ptype][temp].zone_openned = false;
>>>>> + }
>>>>> + }
>>>>> +#endif
>>>>> }
>>>>> kfree(array);
>>>>> }
>>>>> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
>>>>> index e1c0f418aa11..855978ca869f 100644
>>>>> --- a/fs/f2fs/segment.h
>>>>> +++ b/fs/f2fs/segment.h
>>>>> @@ -24,7 +24,8 @@
>>>>> #define IS_DATASEG(t) ((t) <= CURSEG_COLD_DATA)
>>>>> #define IS_NODESEG(t) ((t) >= CURSEG_HOT_NODE && (t) <= CURSEG_COLD_NODE)
>>>>> -#define SE_PAGETYPE(se) ((IS_NODESEG((se)->type) ? NODE : DATA))
>>>>> +#define PAGE_TYPE(t) (IS_NODESEG(t) ? NODE : DATA)
>>>>> +#define SE_PAGETYPE(se) (PAGE_TYPE((se)->type))
>>>>> static inline void sanity_check_seg_type(struct f2fs_sb_info *sbi,
>>>>> unsigned short seg_type)
>>>>> @@ -965,3 +966,12 @@ static inline unsigned int first_zoned_segno(struct f2fs_sb_info *sbi)
>>>>> return GET_SEGNO(sbi, FDEV(devi).start_blk);
>>>>> return 0;
>>>>> }
>>>>> +
>>>>> +static inline enum temp_type type_to_temp(int type)
>>>>> +{
>>>>> + if (IS_HOT(type))
>>>>> + return HOT;
>>>>> + else if (IS_WARM(type))
>>>>> + return WARM;
>>>>> + return COLD;
>>>>> +}
>>>>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
>>>>> index fdf358c7f808..954baa6c100d 100644
>>>>> --- a/fs/f2fs/super.c
>>>>> +++ b/fs/f2fs/super.c
>>>>> @@ -3893,6 +3893,8 @@ static int init_blkz_info(struct f2fs_sb_info *sbi, int devi)
>>>>> sbi->max_open_zones, F2FS_OPTION(sbi).active_logs);
>>>>> return -EINVAL;
>>>>> }
>>>>> +
>>>>> + sema_init(&sbi->available_open_zones, sbi->max_open_zones);
>>>>> }
>>>>> zone_sectors = bdev_zone_sectors(bdev);
>>>>> --
>>>>> 2.40.1
>
>
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