From 00782aaa81cea8d946ab211275f35985bd8a79e7 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Thu, 29 Aug 2024 08:09:58 +0930 Subject: [PATCH] btrfs: interrupt long running operations if the current process is freezing [BUG] There is a bug report that running fstrim will prevent the system from hibernation, result the following dmesg: PM: suspend entry (deep) Filesystems sync: 0.060 seconds Freezing user space processes Freezing user space processes failed after 20.007 seconds (1 tasks refusing to freeze, wq_busy=0): task:fstrim state:D stack:0 pid:15564 tgid:15564 ppid:1 flags:0x00004006 Call Trace: __schedule+0x381/0x1540 schedule+0x24/0xb0 schedule_timeout+0x1ea/0x2a0 io_schedule_timeout+0x19/0x50 wait_for_completion_io+0x78/0x140 submit_bio_wait+0xaa/0xc0 blkdev_issue_discard+0x65/0xb0 btrfs_issue_discard+0xcf/0x160 [btrfs 7ab35b9b86062a46f6ff578bb32d55ecf8e6bf82] btrfs_discard_extent+0x120/0x2a0 [btrfs 7ab35b9b86062a46f6ff578bb32d55ecf8e6bf82] do_trimming+0xd4/0x220 [btrfs 7ab35b9b86062a46f6ff578bb32d55ecf8e6bf82] trim_bitmaps+0x418/0x520 [btrfs 7ab35b9b86062a46f6ff578bb32d55ecf8e6bf82] btrfs_trim_block_group+0xcb/0x130 [btrfs 7ab35b9b86062a46f6ff578bb32d55ecf8e6bf82] btrfs_trim_fs+0x119/0x460 [btrfs 7ab35b9b86062a46f6ff578bb32d55ecf8e6bf82] btrfs_ioctl_fitrim+0xfb/0x160 [btrfs 7ab35b9b86062a46f6ff578bb32d55ecf8e6bf82] btrfs_ioctl+0x11cc/0x29f0 [btrfs 7ab35b9b86062a46f6ff578bb32d55ecf8e6bf82] __x64_sys_ioctl+0x92/0xd0 do_syscall_64+0x5b/0x80 entry_SYSCALL_64_after_hwframe+0x7c/0xe6 RIP: 0033:0x7f5f3b529f9b RSP: 002b:00007fff279ebc20 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fff279ebd60 RCX: 00007f5f3b529f9b RDX: 00007fff279ebc90 RSI: 00000000c0185879 RDI: 0000000000000003 RBP: 000055748718b2d0 R08: 00005574871899e8 R09: 00007fff279eb010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 000055748718ac40 R14: 000055748718b290 R15: 000055748718b290 OOM killer enabled. Restarting tasks ... done. random: crng reseeded on system resumption PM: suspend exit PM: suspend entry (s2idle) Filesystems sync: 0.047 seconds [CAUSE] PM code is freezing all user space processes before entering hibernation/suspension, but if a user space process is trapping into the kernel for a long running operation, it will not be frozen since it's still inside kernel. Normally those long running operations check for fatal signals and exit early, but freezing user space processes is not done by signals but a different infrastructure. Unfortunately btrfs only checks fatal signals but not if the current task is being frozen. [FIX] Introduce a helper, btrfs_task_interrupted(), to check both fatal signals and freezing status, and apply to all long running operations, with dedicated error code: - reflink (-EINTR) - fstrim (-ERESTARTSYS) - relocation (-ECANCELD) - llseek (-EINTR) - defrag (-EAGAIN) - fiemap (-EINTR) Reported-by: Rolf Wentland Link: https://bugzilla.suse.com/show_bug.cgi?id=1229737 Reviewed-by: Josef Bacik Signed-off-by: Qu Wenruo --- fs/btrfs/defrag.h | 3 ++- fs/btrfs/extent-tree.c | 3 +-- fs/btrfs/fiemap.c | 2 +- fs/btrfs/file.c | 2 +- fs/btrfs/free-space-cache.c | 5 ++--- fs/btrfs/misc.h | 7 +++++++ fs/btrfs/reflink.c | 2 +- fs/btrfs/relocation.c | 2 +- 8 files changed, 16 insertions(+), 10 deletions(-) diff --git a/fs/btrfs/defrag.h b/fs/btrfs/defrag.h index 6b7596c4f0dc12..f9dd97352574a0 100644 --- a/fs/btrfs/defrag.h +++ b/fs/btrfs/defrag.h @@ -5,6 +5,7 @@ #include #include +#include "misc.h" struct inode; struct file_ra_state; @@ -25,7 +26,7 @@ int btrfs_defrag_root(struct btrfs_root *root); static inline int btrfs_defrag_cancelled(struct btrfs_fs_info *fs_info) { - return signal_pending(current); + return signal_pending(current) || btrfs_task_interrupted(); } #endif diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index feec49e6f9c801..81ed4d1359aaff 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4,7 +4,6 @@ */ #include -#include #include #include #include @@ -6459,7 +6458,7 @@ static int btrfs_trim_free_extents(struct btrfs_device *device, u64 *trimmed) start += len; *trimmed += bytes; - if (fatal_signal_pending(current)) { + if (btrfs_task_interrupted()) { ret = -ERESTARTSYS; break; } diff --git a/fs/btrfs/fiemap.c b/fs/btrfs/fiemap.c index df7f09f3b02e06..a3d9b8922bb966 100644 --- a/fs/btrfs/fiemap.c +++ b/fs/btrfs/fiemap.c @@ -794,7 +794,7 @@ static int extent_fiemap(struct btrfs_inode *inode, prev_extent_end = extent_end; next_item: - if (fatal_signal_pending(current)) { + if (btrfs_task_interrupted()) { ret = -EINTR; goto out_unlock; } diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 76f4cc686af9fa..088f06dca16eea 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -3676,7 +3676,7 @@ static loff_t find_desired_extent(struct file *file, loff_t offset, int whence) start = extent_end; last_extent_end = extent_end; path->slots[0]++; - if (fatal_signal_pending(current)) { + if (btrfs_task_interrupted()) { ret = -EINTR; goto out; } diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index eaa1dbd313528c..7c9506ee7be611 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -5,7 +5,6 @@ #include #include -#include #include #include #include @@ -3809,7 +3808,7 @@ static int trim_no_bitmap(struct btrfs_block_group *block_group, if (async && *total_trimmed) break; - if (fatal_signal_pending(current)) { + if (btrfs_task_interrupted()) { ret = -ERESTARTSYS; break; } @@ -4000,7 +3999,7 @@ static int trim_bitmaps(struct btrfs_block_group *block_group, } block_group->discard_cursor = start; - if (fatal_signal_pending(current)) { + if (btrfs_task_interrupted()) { if (start != offset) reset_trimming_bitmap(ctl, offset); ret = -ERESTARTSYS; diff --git a/fs/btrfs/misc.h b/fs/btrfs/misc.h index 0d599fd847c9bf..fcc9715b55fe7e 100644 --- a/fs/btrfs/misc.h +++ b/fs/btrfs/misc.h @@ -9,6 +9,8 @@ #include #include #include +#include +#include /* * Enumerate bits using enum autoincrement. Define the @name as the n-th bit. @@ -163,4 +165,9 @@ static inline bool bitmap_test_range_all_zero(const unsigned long *addr, return (found_set == start + nbits); } +static inline bool btrfs_task_interrupted(void) +{ + return fatal_signal_pending(current) || freezing(current); +} + #endif diff --git a/fs/btrfs/reflink.c b/fs/btrfs/reflink.c index df6b93b927cd85..f2063d388553c7 100644 --- a/fs/btrfs/reflink.c +++ b/fs/btrfs/reflink.c @@ -564,7 +564,7 @@ static int btrfs_clone(struct inode *src, struct inode *inode, btrfs_release_path(path); key.offset = prev_extent_end; - if (fatal_signal_pending(current)) { + if (btrfs_task_interrupted()) { ret = -EINTR; goto out; } diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index ea4ed85919ec8f..feafa46ef7a57a 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -2936,7 +2936,7 @@ noinline int btrfs_should_cancel_balance(const struct btrfs_fs_info *fs_info) { return atomic_read(&fs_info->balance_cancel_req) || atomic_read(&fs_info->reloc_cancel_req) || - fatal_signal_pending(current); + btrfs_task_interrupted(); } ALLOW_ERROR_INJECTION(btrfs_should_cancel_balance, TRUE);