Messages in this thread | | | Subject | Re: [f2fs-dev] [PATCH 1/3] f2fs: turn off atomic writes when deteting abnormal behaviors | From | Chao Yu <> | Date | Mon, 23 Jul 2018 21:27:18 +0800 |
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On 2018/7/23 21:03, Jaegeuk Kim wrote: > On 07/16, Chao Yu wrote: >> On 2018/7/15 9:11, Jaegeuk Kim wrote: >>> In order to prevent abusing atomic writes by abnormal users, we've added a >>> threshold, 20% over memory footprint, which disallows further atomic writes. >>> Previously, however, SQLite doesn't know the files became normal, so that >>> it could write stale data and commit on revoked normal database file. >>> >>> Once f2fs detects such the abnormal behavior, this patch simply disables >>> all the atomic operations such as: >>> - write_begin() gives EINVAL to avoid stale data writes, and SQLite will call >>> F2FS_IOC_ABORT_VOLATILE_WRITE to notify aborting the transaction, >>> - F2FS_IOC_START_ATOMIC_WRITE gives EINVAL for SQLite to fall back normal >>> journal_mode, >>> - F2FS_IOC_COMMIT_ATOMIC_WRITE gives EINVAL, if the file was revoked, so that >>> Framework retries to submit the transaction given propagated SQLite error. >>> >>> Note that, this patch also turns off atomic operations, if foreground GC tries >>> to move atomic files too frequently. >> >> Well, how about just keeping original implementation: shutdown atomic write for >> those files which are really affect fggc? Since intention of the original >> behavior is targeting to abnormal atomic write usage, e.g. open atomic_write >> file for very long time, then fggc will be blocked each time when moving its >> block. So shutdown it, fggc will recover. > > The point here is stopping sqlite to keep going wrong data writes even after > we already revoked blocks.
Yes, that's correct, what I mean is that if we can do that with smaller granularity like just revoke blocks for file which is blocking fggc, it will affect system/sqlite flow much less than forcing closing all atomic_write.
Thanks,
> > Thanks, > >> >> Thanks, >> >>> >>> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> >>> --- >>> fs/f2fs/data.c | 7 ++++--- >>> fs/f2fs/f2fs.h | 4 ++-- >>> fs/f2fs/file.c | 6 +++++- >>> fs/f2fs/gc.c | 4 +--- >>> fs/f2fs/segment.c | 21 +++++++++++---------- >>> 5 files changed, 23 insertions(+), 19 deletions(-) >>> >>> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c >>> index 5e53d210e222..c9e75aa61c24 100644 >>> --- a/fs/f2fs/data.c >>> +++ b/fs/f2fs/data.c >>> @@ -2247,8 +2247,9 @@ static int f2fs_write_begin(struct file *file, struct address_space *mapping, >>> trace_f2fs_write_begin(inode, pos, len, flags); >>> >>> if (f2fs_is_atomic_file(inode) && >>> - !f2fs_available_free_memory(sbi, INMEM_PAGES)) { >>> - err = -ENOMEM; >>> + (is_sbi_flag_set(sbi, SBI_DISABLE_ATOMIC_WRITE) || >>> + !f2fs_available_free_memory(sbi, INMEM_PAGES))) { >>> + err = -EINVAL; >>> drop_atomic = true; >>> goto fail; >>> } >>> @@ -2331,7 +2332,7 @@ static int f2fs_write_begin(struct file *file, struct address_space *mapping, >>> f2fs_put_page(page, 1); >>> f2fs_write_failed(mapping, pos + len); >>> if (drop_atomic) >>> - f2fs_drop_inmem_pages_all(sbi, false); >>> + f2fs_disable_atomic_write(sbi); >>> return err; >>> } >>> >>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h >>> index 4d8b1de83143..1d5c8d543eda 100644 >>> --- a/fs/f2fs/f2fs.h >>> +++ b/fs/f2fs/f2fs.h >>> @@ -621,7 +621,6 @@ enum { >>> >>> enum { >>> GC_FAILURE_PIN, >>> - GC_FAILURE_ATOMIC, >>> MAX_GC_FAILURE >>> }; >>> >>> @@ -1066,6 +1065,7 @@ enum { >>> SBI_POR_DOING, /* recovery is doing or not */ >>> SBI_NEED_SB_WRITE, /* need to recover superblock */ >>> SBI_NEED_CP, /* need to checkpoint */ >>> + SBI_DISABLE_ATOMIC_WRITE, /* turn off atomic write */ >>> }; >>> >>> enum { >>> @@ -2833,7 +2833,7 @@ void f2fs_destroy_node_manager_caches(void); >>> */ >>> bool f2fs_need_SSR(struct f2fs_sb_info *sbi); >>> void f2fs_register_inmem_page(struct inode *inode, struct page *page); >>> -void f2fs_drop_inmem_pages_all(struct f2fs_sb_info *sbi, bool gc_failure); >>> +void f2fs_disable_atomic_write(struct f2fs_sb_info *sbi); >>> void f2fs_drop_inmem_pages(struct inode *inode); >>> void f2fs_drop_inmem_page(struct inode *inode, struct page *page); >>> int f2fs_commit_inmem_pages(struct inode *inode); >>> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c >>> index 6880c6f78d58..b029a4ed3bb0 100644 >>> --- a/fs/f2fs/file.c >>> +++ b/fs/f2fs/file.c >>> @@ -1682,6 +1682,9 @@ static int f2fs_ioc_start_atomic_write(struct file *filp) >>> if (!S_ISREG(inode->i_mode)) >>> return -EINVAL; >>> >>> + if (is_sbi_flag_set(F2FS_I_SB(inode), SBI_DISABLE_ATOMIC_WRITE)) >>> + return -EINVAL; >>> + >>> ret = mnt_want_write_file(filp); >>> if (ret) >>> return ret; >>> @@ -1750,7 +1753,6 @@ static int f2fs_ioc_commit_atomic_write(struct file *filp) >>> ret = f2fs_do_sync_file(filp, 0, LLONG_MAX, 0, true); >>> if (!ret) { >>> clear_inode_flag(inode, FI_ATOMIC_FILE); >>> - F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC] = 0; >>> stat_dec_atomic_write(inode); >>> } >>> } else { >>> @@ -1853,6 +1855,8 @@ static int f2fs_ioc_abort_volatile_write(struct file *filp) >>> ret = f2fs_do_sync_file(filp, 0, LLONG_MAX, 0, true); >>> } >>> >>> + clear_inode_flag(inode, FI_ATOMIC_REVOKE_REQUEST); >>> + >>> inode_unlock(inode); >>> >>> mnt_drop_write_file(filp); >>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c >>> index 9093be6e7a7d..6d762f3cdfc7 100644 >>> --- a/fs/f2fs/gc.c >>> +++ b/fs/f2fs/gc.c >>> @@ -629,7 +629,6 @@ static void move_data_block(struct inode *inode, block_t bidx, >>> goto out; >>> >>> if (f2fs_is_atomic_file(inode)) { >>> - F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC]++; >>> F2FS_I_SB(inode)->skipped_atomic_files[gc_type]++; >>> goto out; >>> } >>> @@ -745,7 +744,6 @@ static void move_data_page(struct inode *inode, block_t bidx, int gc_type, >>> goto out; >>> >>> if (f2fs_is_atomic_file(inode)) { >>> - F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC]++; >>> F2FS_I_SB(inode)->skipped_atomic_files[gc_type]++; >>> goto out; >>> } >>> @@ -1100,7 +1098,7 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync, >>> if (has_not_enough_free_secs(sbi, sec_freed, 0)) { >>> if (skipped_round > MAX_SKIP_ATOMIC_COUNT && >>> skipped_round * 2 >= round) >>> - f2fs_drop_inmem_pages_all(sbi, true); >>> + f2fs_disable_atomic_write(sbi); >>> segno = NULL_SEGNO; >>> goto gc_more; >>> } >>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c >>> index 9efce174c51a..05877a2f1894 100644 >>> --- a/fs/f2fs/segment.c >>> +++ b/fs/f2fs/segment.c >>> @@ -274,11 +274,14 @@ static int __revoke_inmem_pages(struct inode *inode, >>> return err; >>> } >>> >>> -void f2fs_drop_inmem_pages_all(struct f2fs_sb_info *sbi, bool gc_failure) >>> +void f2fs_disable_atomic_write(struct f2fs_sb_info *sbi) >>> { >>> struct list_head *head = &sbi->inode_list[ATOMIC_FILE]; >>> struct inode *inode; >>> struct f2fs_inode_info *fi; >>> + >>> + /* just turn it off */ >>> + set_sbi_flag(sbi, SBI_DISABLE_ATOMIC_WRITE); >>> next: >>> spin_lock(&sbi->inode_lock[ATOMIC_FILE]); >>> if (list_empty(head)) { >>> @@ -290,17 +293,16 @@ void f2fs_drop_inmem_pages_all(struct f2fs_sb_info *sbi, bool gc_failure) >>> spin_unlock(&sbi->inode_lock[ATOMIC_FILE]); >>> >>> if (inode) { >>> - if (gc_failure) { >>> - if (fi->i_gc_failures[GC_FAILURE_ATOMIC]) >>> - goto drop; >>> - goto skip; >>> + inode_lock(inode); >>> + /* need to check whether it was already revoked */ >>> + if (f2fs_is_atomic_file(inode)) { >>> + f2fs_drop_inmem_pages(inode); >>> + set_inode_flag(inode, FI_ATOMIC_REVOKE_REQUEST); >>> } >>> -drop: >>> - set_inode_flag(inode, FI_ATOMIC_REVOKE_REQUEST); >>> - f2fs_drop_inmem_pages(inode); >>> + inode_unlock(inode); >>> iput(inode); >>> } >>> -skip: >>> + >>> congestion_wait(BLK_RW_ASYNC, HZ/50); >>> cond_resched(); >>> goto next; >>> @@ -320,7 +322,6 @@ void f2fs_drop_inmem_pages(struct inode *inode) >>> mutex_unlock(&fi->inmem_lock); >>> >>> clear_inode_flag(inode, FI_ATOMIC_FILE); >>> - fi->i_gc_failures[GC_FAILURE_ATOMIC] = 0; >>> stat_dec_atomic_write(inode); >>> } >>> >>> > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel >
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