Messages in this thread | | | Date | Wed, 30 Oct 2019 09:09:42 -0700 | From | Jaegeuk Kim <> | Subject | Re: [f2fs-dev] [PATCH 1/2] f2fs: support aligned pinned file |
| |
On 10/26, Chao Yu wrote: > On 2019/10/26 2:18, Jaegeuk Kim wrote: > > On 10/24, Chao Yu wrote: > >> Hi Jaegeuk, > >> > >> On 2019/10/23 1:16, Jaegeuk Kim wrote: > >>> This patch supports 2MB-aligned pinned file, which can guarantee no GC at all > >>> by allocating fully valid 2MB segment. > >>> > >>> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> > >>> --- > >>> fs/f2fs/f2fs.h | 4 +++- > >>> fs/f2fs/file.c | 39 ++++++++++++++++++++++++++++++++++----- > >>> fs/f2fs/recovery.c | 2 +- > >>> fs/f2fs/segment.c | 21 ++++++++++++++++++++- > >>> fs/f2fs/segment.h | 2 ++ > >>> fs/f2fs/super.c | 1 + > >>> fs/f2fs/sysfs.c | 2 ++ > >>> 7 files changed, 63 insertions(+), 8 deletions(-) > >>> > >>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > >>> index ca342f4c7db1..c681f51e351b 100644 > >>> --- a/fs/f2fs/f2fs.h > >>> +++ b/fs/f2fs/f2fs.h > >>> @@ -890,6 +890,7 @@ enum { > >>> CURSEG_WARM_NODE, /* direct node blocks of normal files */ > >>> CURSEG_COLD_NODE, /* indirect node blocks */ > >>> NO_CHECK_TYPE, > >>> + CURSEG_COLD_DATA_PINNED,/* cold data for pinned file */ > >>> }; > >>> > >>> struct flush_cmd { > >>> @@ -1301,6 +1302,7 @@ struct f2fs_sb_info { > >>> > >>> /* threshold for gc trials on pinned files */ > >>> u64 gc_pin_file_threshold; > >>> + struct rw_semaphore pin_sem; > >>> > >>> /* maximum # of trials to find a victim segment for SSR and GC */ > >>> unsigned int max_victim_search; > >>> @@ -3116,7 +3118,7 @@ void f2fs_release_discard_addrs(struct f2fs_sb_info *sbi); > >>> int f2fs_npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra); > >>> void allocate_segment_for_resize(struct f2fs_sb_info *sbi, int type, > >>> unsigned int start, unsigned int end); > >>> -void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi); > >>> +void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi, int type); > >>> int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range); > >>> bool f2fs_exist_trim_candidates(struct f2fs_sb_info *sbi, > >>> struct cp_control *cpc); > >>> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > >>> index 29bc0a542759..f6c038e8a6a7 100644 > >>> --- a/fs/f2fs/file.c > >>> +++ b/fs/f2fs/file.c > >>> @@ -1545,12 +1545,41 @@ static int expand_inode_data(struct inode *inode, loff_t offset, > >>> if (off_end) > >>> map.m_len++; > >>> > >>> - if (f2fs_is_pinned_file(inode)) > >>> - map.m_seg_type = CURSEG_COLD_DATA; > >>> + if (!map.m_len) > >>> + return 0; > >>> + > >>> + if (f2fs_is_pinned_file(inode)) { > >>> + block_t len = (map.m_len >> sbi->log_blocks_per_seg) << > >>> + sbi->log_blocks_per_seg; > >>> + block_t done = 0; > >>> + > >>> + if (map.m_len % sbi->blocks_per_seg) > >>> + len += sbi->blocks_per_seg; > >>> > >>> - err = f2fs_map_blocks(inode, &map, 1, (f2fs_is_pinned_file(inode) ? > >>> - F2FS_GET_BLOCK_PRE_DIO : > >>> - F2FS_GET_BLOCK_PRE_AIO)); > >>> + map.m_len = sbi->blocks_per_seg; > >>> +next_alloc: > >>> + mutex_lock(&sbi->gc_mutex); > >>> + err = f2fs_gc(sbi, true, false, NULL_SEGNO); > >>> + if (err && err != -ENODATA && err != -EAGAIN) > >>> + goto out_err; > >> > >> To grab enough free space? > >> > >> Shouldn't we call > >> > >> if (has_not_enough_free_secs(sbi, 0, 0)) { > >> mutex_lock(&sbi->gc_mutex); > >> f2fs_gc(sbi, false, false, NULL_SEGNO); > >> } > > > > The above calls gc all the time. Do we need this? > > Hmmm... my concern is why we need to run foreground GC even if there is enough > free space..
In order to get the free segment easily?
> > > > >> > >>> + > >>> + down_write(&sbi->pin_sem); > >>> + map.m_seg_type = CURSEG_COLD_DATA_PINNED; > >>> + f2fs_allocate_new_segments(sbi, CURSEG_COLD_DATA); > >>> + err = f2fs_map_blocks(inode, &map, 1, F2FS_GET_BLOCK_PRE_DIO); > >>> + up_write(&sbi->pin_sem); > >>> + > >>> + done += map.m_len; > >>> + len -= map.m_len; > >>> + map.m_lblk += map.m_len; > >>> + if (!err && len) > >>> + goto next_alloc; > >>> + > >>> + map.m_len = done; > >>> + } else { > >>> + err = f2fs_map_blocks(inode, &map, 1, F2FS_GET_BLOCK_PRE_AIO); > >>> + } > >>> +out_err: > >>> if (err) { > >>> pgoff_t last_off; > >>> > >>> diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c > >>> index 783773e4560d..76477f71d4ee 100644 > >>> --- a/fs/f2fs/recovery.c > >>> +++ b/fs/f2fs/recovery.c > >>> @@ -711,7 +711,7 @@ static int recover_data(struct f2fs_sb_info *sbi, struct list_head *inode_list, > >>> f2fs_put_page(page, 1); > >>> } > >>> if (!err) > >>> - f2fs_allocate_new_segments(sbi); > >>> + f2fs_allocate_new_segments(sbi, NO_CHECK_TYPE); > >>> return err; > >>> } > >>> > >>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > >>> index 25c750cd0272..253d72c2663c 100644 > >>> --- a/fs/f2fs/segment.c > >>> +++ b/fs/f2fs/segment.c > >>> @@ -2690,7 +2690,7 @@ void allocate_segment_for_resize(struct f2fs_sb_info *sbi, int type, > >>> up_read(&SM_I(sbi)->curseg_lock); > >>> } > >>> > >>> -void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi) > >>> +void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi, int type) > >>> { > >>> struct curseg_info *curseg; > >>> unsigned int old_segno; > >>> @@ -2699,6 +2699,9 @@ void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi) > >>> down_write(&SIT_I(sbi)->sentry_lock); > >>> > >>> for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) { > >>> + if (type != NO_CHECK_TYPE && i != type) > >>> + continue; > >>> + > >>> curseg = CURSEG_I(sbi, i); > >>> old_segno = curseg->segno; > >>> SIT_I(sbi)->s_ops->allocate_segment(sbi, i, true); > >>> @@ -3068,6 +3071,19 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page, > >>> { > >>> struct sit_info *sit_i = SIT_I(sbi); > >>> struct curseg_info *curseg = CURSEG_I(sbi, type); > >>> + bool put_pin_sem = false; > >>> + > >>> + if (type == CURSEG_COLD_DATA) { > >>> + /* GC during CURSEG_COLD_DATA_PINNED allocation */ > >>> + if (down_read_trylock(&sbi->pin_sem)) { > >>> + put_pin_sem = true; > >>> + } else { > >>> + type = CURSEG_WARM_DATA; > >>> + curseg = CURSEG_I(sbi, type); > >> > >> It will mix pending cold data into warm area... rather than recovering curseg to > >> write pointer of last cold segment? > >> > >> I know maybe that fallocate aligned address could be corner case, but I guess > >> there should be some better solutions can handle race case more effectively. > >> > >> One solution could be: allocating a virtual log header to select free segment as > >> 2m-aligned space target. > > > > I thought about that, but concluded to avoid too much changes. > > We have an unupstreamed feature which is based on virtual log header, I can > introduce that basic virtual log fwk, which can be used for aligned allocation > and later new features, would you like to check that? > > Thanks, > > > > >> > >> Thanks, > >> > >>> + } > >>> + } else if (type == CURSEG_COLD_DATA_PINNED) { > >>> + type = CURSEG_COLD_DATA; > >>> + } > >>> > >>> down_read(&SM_I(sbi)->curseg_lock); > >>> > >>> @@ -3133,6 +3149,9 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page, > >>> mutex_unlock(&curseg->curseg_mutex); > >>> > >>> up_read(&SM_I(sbi)->curseg_lock); > >>> + > >>> + if (put_pin_sem) > >>> + up_read(&sbi->pin_sem); > >>> } > >>> > >>> static void update_device_state(struct f2fs_io_info *fio) > >>> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h > >>> index 325781a1ae4d..a95467b202ea 100644 > >>> --- a/fs/f2fs/segment.h > >>> +++ b/fs/f2fs/segment.h > >>> @@ -313,6 +313,8 @@ struct sit_entry_set { > >>> */ > >>> static inline struct curseg_info *CURSEG_I(struct f2fs_sb_info *sbi, int type) > >>> { > >>> + if (type == CURSEG_COLD_DATA_PINNED) > >>> + type = CURSEG_COLD_DATA; > >>> return (struct curseg_info *)(SM_I(sbi)->curseg_array + type); > >>> } > >>> > >>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c > >>> index f320fd11db48..c02a47ce551b 100644 > >>> --- a/fs/f2fs/super.c > >>> +++ b/fs/f2fs/super.c > >>> @@ -2853,6 +2853,7 @@ static void init_sb_info(struct f2fs_sb_info *sbi) > >>> spin_lock_init(&sbi->dev_lock); > >>> > >>> init_rwsem(&sbi->sb_lock); > >>> + init_rwsem(&sbi->pin_sem); > >>> } > >>> > >>> static int init_percpu_info(struct f2fs_sb_info *sbi) > >>> diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c > >>> index b558b64a4c9c..f164959e4224 100644 > >>> --- a/fs/f2fs/sysfs.c > >>> +++ b/fs/f2fs/sysfs.c > >>> @@ -154,6 +154,8 @@ static ssize_t features_show(struct f2fs_attr *a, > >>> if (f2fs_sb_has_casefold(sbi)) > >>> len += snprintf(buf + len, PAGE_SIZE - len, "%s%s", > >>> len ? ", " : "", "casefold"); > >>> + len += snprintf(buf + len, PAGE_SIZE - len, "%s%s", > >>> + len ? ", " : "", "pin_file"); > >>> len += snprintf(buf + len, PAGE_SIZE - len, "\n"); > >>> return len; > >>> } > >>> > > . > >
| |