From patchwork Wed Oct 24 12:24:01 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lu Fengqi X-Patchwork-Id: 10654583 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4676F17F3 for ; Wed, 24 Oct 2018 12:24:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 304062A03F for ; Wed, 24 Oct 2018 12:24:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 24CA02A265; Wed, 24 Oct 2018 12:24:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 834762A26A for ; Wed, 24 Oct 2018 12:24:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727543AbeJXUwR (ORCPT ); Wed, 24 Oct 2018 16:52:17 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:51970 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727411AbeJXUwQ (ORCPT ); Wed, 24 Oct 2018 16:52:16 -0400 X-IronPort-AV: E=Sophos;i="5.43,368,1503331200"; d="scan'208";a="46658921" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 24 Oct 2018 20:24:15 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id CA4114B714A5; Wed, 24 Oct 2018 20:24:11 +0800 (CST) Received: from fnst.lan (10.167.226.155) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.408.0; Wed, 24 Oct 2018 20:24:16 +0800 From: Lu Fengqi To: CC: Qu Wenruo Subject: [PATCH 1/3] btrfs: extent-tree: Detect bytes_may_use underflow earlier Date: Wed, 24 Oct 2018 20:24:01 +0800 Message-ID: <20181024122403.17418-2-lufq.fnst@cn.fujitsu.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181024122403.17418-1-lufq.fnst@cn.fujitsu.com> References: <20181024122403.17418-1-lufq.fnst@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.155] X-yoursite-MailScanner-ID: CA4114B714A5.A78D2 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: lufq.fnst@cn.fujitsu.com Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Qu Wenruo Although we have space_info::bytes_may_use underflow detection in btrfs_free_reserved_data_space_noquota(), we have more callers who are subtracting number from space_info::bytes_may_use. So instead of doing underflow detection for every caller, introduce a new wrapper update_bytes_may_use() to replace open coded bytes_may_use modifiers. This also introduce a macro to declare more wrappers, but currently space_info::bytes_may_use is the mostly interesting one. Signed-off-by: Qu Wenruo --- fs/btrfs/extent-tree.c | 44 +++++++++++++++++++++++++++--------------- 1 file changed, 28 insertions(+), 16 deletions(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index a1febf155747..c0147a1307e7 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -51,6 +51,21 @@ enum { CHUNK_ALLOC_FORCE = 2, }; +/* Helper function to detect various space info bytes underflow */ +#define DECLARE_SPACE_INFO_UPDATE(name) \ +static inline void update_##name(struct btrfs_space_info *sinfo, \ + s64 bytes) \ +{ \ + if (bytes < 0 && sinfo->name < -bytes) { \ + WARN_ON(1); \ + sinfo->name = 0; \ + return; \ + } \ + sinfo->name += bytes; \ +} + +DECLARE_SPACE_INFO_UPDATE(bytes_may_use); + static int __btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_delayed_ref_node *node, u64 parent, u64 root_objectid, u64 owner_objectid, @@ -4256,7 +4271,7 @@ int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes) data_sinfo->flags, bytes, 1); return -ENOSPC; } - data_sinfo->bytes_may_use += bytes; + update_bytes_may_use(data_sinfo, bytes); trace_btrfs_space_reservation(fs_info, "space_info", data_sinfo->flags, bytes, 1); spin_unlock(&data_sinfo->lock); @@ -4309,10 +4324,7 @@ void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start, data_sinfo = fs_info->data_sinfo; spin_lock(&data_sinfo->lock); - if (WARN_ON(data_sinfo->bytes_may_use < len)) - data_sinfo->bytes_may_use = 0; - else - data_sinfo->bytes_may_use -= len; + update_bytes_may_use(data_sinfo, -len); trace_btrfs_space_reservation(fs_info, "space_info", data_sinfo->flags, len, 0); spin_unlock(&data_sinfo->lock); @@ -5108,7 +5120,7 @@ static int wait_reserve_ticket(struct btrfs_fs_info *fs_info, list_del_init(&ticket->list); if (ticket->bytes && ticket->bytes < orig_bytes) { u64 num_bytes = orig_bytes - ticket->bytes; - space_info->bytes_may_use -= num_bytes; + update_bytes_may_use(space_info, -num_bytes); trace_btrfs_space_reservation(fs_info, "space_info", space_info->flags, num_bytes, 0); } @@ -5154,13 +5166,13 @@ static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info, * If not things get more complicated. */ if (used + orig_bytes <= space_info->total_bytes) { - space_info->bytes_may_use += orig_bytes; + update_bytes_may_use(space_info, orig_bytes); trace_btrfs_space_reservation(fs_info, "space_info", space_info->flags, orig_bytes, 1); ret = 0; } else if (can_overcommit(fs_info, space_info, orig_bytes, flush, system_chunk)) { - space_info->bytes_may_use += orig_bytes; + update_bytes_may_use(space_info, orig_bytes); trace_btrfs_space_reservation(fs_info, "space_info", space_info->flags, orig_bytes, 1); ret = 0; @@ -5223,7 +5235,7 @@ static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info, if (ticket.bytes) { if (ticket.bytes < orig_bytes) { u64 num_bytes = orig_bytes - ticket.bytes; - space_info->bytes_may_use -= num_bytes; + update_bytes_may_use(space_info, -num_bytes); trace_btrfs_space_reservation(fs_info, "space_info", space_info->flags, num_bytes, 0); @@ -5407,7 +5419,7 @@ static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info, flush = BTRFS_RESERVE_FLUSH_ALL; goto again; } - space_info->bytes_may_use -= num_bytes; + update_bytes_may_use(space_info, -num_bytes); trace_btrfs_space_reservation(fs_info, "space_info", space_info->flags, num_bytes, 0); spin_unlock(&space_info->lock); @@ -5435,7 +5447,7 @@ static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info, ticket->bytes, 1); list_del_init(&ticket->list); num_bytes -= ticket->bytes; - space_info->bytes_may_use += ticket->bytes; + update_bytes_may_use(space_info, ticket->bytes); ticket->bytes = 0; space_info->tickets_id++; wake_up(&ticket->wait); @@ -5443,7 +5455,7 @@ static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info, trace_btrfs_space_reservation(fs_info, "space_info", space_info->flags, num_bytes, 1); - space_info->bytes_may_use += num_bytes; + update_bytes_may_use(space_info, num_bytes); ticket->bytes -= num_bytes; num_bytes = 0; } @@ -5750,14 +5762,14 @@ static void update_global_block_rsv(struct btrfs_fs_info *fs_info) num_bytes = min(num_bytes, block_rsv->size - block_rsv->reserved); block_rsv->reserved += num_bytes; - sinfo->bytes_may_use += num_bytes; + update_bytes_may_use(sinfo, num_bytes); trace_btrfs_space_reservation(fs_info, "space_info", sinfo->flags, num_bytes, 1); } } else if (block_rsv->reserved > block_rsv->size) { num_bytes = block_rsv->reserved - block_rsv->size; - sinfo->bytes_may_use -= num_bytes; + update_bytes_may_use(sinfo, -num_bytes); trace_btrfs_space_reservation(fs_info, "space_info", sinfo->flags, num_bytes, 0); block_rsv->reserved = block_rsv->size; @@ -6431,7 +6443,7 @@ static int btrfs_add_reserved_bytes(struct btrfs_block_group_cache *cache, } else { cache->reserved += num_bytes; space_info->bytes_reserved += num_bytes; - space_info->bytes_may_use -= ram_bytes; + update_bytes_may_use(space_info, -ram_bytes); if (delalloc) cache->delalloc_bytes += num_bytes; } @@ -6608,7 +6620,7 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info, to_add = min(len, global_rsv->size - global_rsv->reserved); global_rsv->reserved += to_add; - space_info->bytes_may_use += to_add; + update_bytes_may_use(space_info, to_add); if (global_rsv->reserved >= global_rsv->size) global_rsv->full = 1; trace_btrfs_space_reservation(fs_info, From patchwork Wed Oct 24 12:24:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lu Fengqi X-Patchwork-Id: 10654579 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EF83C17E2 for ; Wed, 24 Oct 2018 12:24:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DB3FC2A094 for ; Wed, 24 Oct 2018 12:24:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CF3EE2A265; Wed, 24 Oct 2018 12:24:27 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 61CAB2A094 for ; Wed, 24 Oct 2018 12:24:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727518AbeJXUwP (ORCPT ); Wed, 24 Oct 2018 16:52:15 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:30356 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726812AbeJXUwO (ORCPT ); Wed, 24 Oct 2018 16:52:14 -0400 X-IronPort-AV: E=Sophos;i="5.43,368,1503331200"; d="scan'208";a="46658920" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 24 Oct 2018 20:24:15 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id 63C6B4B714A7 for ; Wed, 24 Oct 2018 20:24:12 +0800 (CST) Received: from fnst.lan (10.167.226.155) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.408.0; Wed, 24 Oct 2018 20:24:17 +0800 From: Lu Fengqi To: Subject: [PATCH 2/3] btrfs: extent-tree: Detect bytes_pinned underflow earlier Date: Wed, 24 Oct 2018 20:24:02 +0800 Message-ID: <20181024122403.17418-3-lufq.fnst@cn.fujitsu.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181024122403.17418-1-lufq.fnst@cn.fujitsu.com> References: <20181024122403.17418-1-lufq.fnst@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.155] X-yoursite-MailScanner-ID: 63C6B4B714A7.A81F9 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: lufq.fnst@cn.fujitsu.com Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Introduce a new wrapper update_bytes_pinned to replace open coded bytes_pinned modifiers. Signed-off-by: Lu Fengqi --- fs/btrfs/extent-tree.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index c0147a1307e7..bb91db944d21 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -65,6 +65,7 @@ static inline void update_##name(struct btrfs_space_info *sinfo, \ } DECLARE_SPACE_INFO_UPDATE(bytes_may_use); +DECLARE_SPACE_INFO_UPDATE(bytes_pinned); static int __btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_delayed_ref_node *node, u64 parent, @@ -6163,7 +6164,7 @@ static int update_block_group(struct btrfs_trans_handle *trans, old_val -= num_bytes; btrfs_set_block_group_used(&cache->item, old_val); cache->pinned += num_bytes; - cache->space_info->bytes_pinned += num_bytes; + update_bytes_pinned(cache->space_info, num_bytes); cache->space_info->bytes_used -= num_bytes; cache->space_info->disk_used -= num_bytes * factor; spin_unlock(&cache->lock); @@ -6234,7 +6235,7 @@ static int pin_down_extent(struct btrfs_fs_info *fs_info, spin_lock(&cache->space_info->lock); spin_lock(&cache->lock); cache->pinned += num_bytes; - cache->space_info->bytes_pinned += num_bytes; + update_bytes_pinned(cache->space_info, num_bytes); if (reserved) { cache->reserved -= num_bytes; cache->space_info->bytes_reserved -= num_bytes; @@ -6599,7 +6600,7 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info, spin_lock(&space_info->lock); spin_lock(&cache->lock); cache->pinned -= len; - space_info->bytes_pinned -= len; + update_bytes_pinned(space_info, -len); trace_btrfs_space_reservation(fs_info, "pinned", space_info->flags, len, 0); @@ -10710,7 +10711,7 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info) spin_lock(&space_info->lock); spin_lock(&block_group->lock); - space_info->bytes_pinned -= block_group->pinned; + update_bytes_pinned(space_info, -block_group->pinned); space_info->bytes_readonly += block_group->pinned; percpu_counter_add_batch(&space_info->total_bytes_pinned, -block_group->pinned, From patchwork Wed Oct 24 12:24:03 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lu Fengqi X-Patchwork-Id: 10654581 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0DF1A13BF for ; Wed, 24 Oct 2018 12:24:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EA8662A265 for ; Wed, 24 Oct 2018 12:24:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E280A2A309; Wed, 24 Oct 2018 12:24:27 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3E72A2A28A for ; Wed, 24 Oct 2018 12:24:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727444AbeJXUwN (ORCPT ); Wed, 24 Oct 2018 16:52:13 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:30356 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726812AbeJXUwN (ORCPT ); Wed, 24 Oct 2018 16:52:13 -0400 X-IronPort-AV: E=Sophos;i="5.43,368,1503331200"; d="scan'208";a="46658918" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 24 Oct 2018 20:24:15 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id DA3074B714A9 for ; Wed, 24 Oct 2018 20:24:12 +0800 (CST) Received: from fnst.lan (10.167.226.155) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.408.0; Wed, 24 Oct 2018 20:24:18 +0800 From: Lu Fengqi To: Subject: [PATCH 3/3] btrfs: fix pinned underflow after transaction aborted Date: Wed, 24 Oct 2018 20:24:03 +0800 Message-ID: <20181024122403.17418-4-lufq.fnst@cn.fujitsu.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181024122403.17418-1-lufq.fnst@cn.fujitsu.com> References: <20181024122403.17418-1-lufq.fnst@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.155] X-yoursite-MailScanner-ID: DA3074B714A9.A77E7 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: lufq.fnst@cn.fujitsu.com Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When running generic/475, we may get the following warning in the dmesg. [ 6902.102154] WARNING: CPU: 3 PID: 18013 at fs/btrfs/extent-tree.c:9776 btrfs_free_block_groups+0x2af/0x3b0 [btrfs] [ 6902.104886] Modules linked in: btrfs(O) xor zstd_decompress zstd_compress xxhash raid6_pq efivarfs xfs nvme nvme_core [last unloaded: btrfs] [ 6902.109160] CPU: 3 PID: 18013 Comm: umount Tainted: G W O 4.19.0-rc8+ #8 [ 6902.110971] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 [ 6902.112857] RIP: 0010:btrfs_free_block_groups+0x2af/0x3b0 [btrfs] [ 6902.114377] Code: c6 48 89 04 24 48 8b 83 50 17 00 00 48 39 c6 0f 84 ab 00 00 00 4c 8b ab 50 17 00 00 49 83 bd 50 ff ff ff 00 0f 84 b4 00 00 00 <0f> 0b 31 c9 49 8d b5 f8 fe ff ff 31 d2 48 89 df e8 fc 76 ff ff 49 [ 6902.118921] RSP: 0018:ffffc9000459bdb0 EFLAGS: 00010286 [ 6902.120315] RAX: ffff880175050bb0 RBX: ffff8801124a8000 RCX: 0000000000170007 [ 6902.121969] RDX: 0000000000000002 RSI: 0000000000170007 RDI: ffffffff8125fb74 [ 6902.123716] RBP: ffff880175055d10 R08: 0000000000000000 R09: 0000000000000000 [ 6902.125417] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880175055d88 [ 6902.127129] R13: ffff880175050bb0 R14: 0000000000000000 R15: dead000000000100 [ 6902.129060] FS: 00007f4507223780(0000) GS:ffff88017ba00000(0000) knlGS:0000000000000000 [ 6902.130996] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6902.132558] CR2: 00005623599cac78 CR3: 000000014b700001 CR4: 00000000003606e0 [ 6902.134270] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 6902.135981] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 6902.137836] Call Trace: [ 6902.138939] close_ctree+0x171/0x330 [btrfs] [ 6902.140181] ? kthread_stop+0x146/0x1f0 [ 6902.141277] generic_shutdown_super+0x6c/0x100 [ 6902.142517] kill_anon_super+0x14/0x30 [ 6902.143554] btrfs_kill_super+0x13/0x100 [btrfs] [ 6902.144790] deactivate_locked_super+0x2f/0x70 [ 6902.146014] cleanup_mnt+0x3b/0x70 [ 6902.147020] task_work_run+0x9e/0xd0 [ 6902.148036] do_syscall_64+0x470/0x600 [ 6902.149142] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 6902.150375] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 6902.151640] RIP: 0033:0x7f45077a6a7b [ 6902.152782] Code: 23 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 90 f3 0f 1e fa 31 f6 e9 05 00 00 00 90 0f 1f 40 00 f3 0f 1e fa b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d b5 23 0c 00 f7 d8 64 89 01 48 [ 6902.157324] RSP: 002b:00007ffd589f3e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [ 6902.159187] RAX: 0000000000000000 RBX: 000055e8eec732b0 RCX: 00007f45077a6a7b [ 6902.160834] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000055e8eec73490 [ 6902.162526] RBP: 0000000000000000 R08: 000055e8eec734b0 R09: 00007ffd589f26c0 [ 6902.164141] R10: 0000000000000000 R11: 0000000000000246 R12: 000055e8eec73490 [ 6902.165815] R13: 00007f4507ac61a4 R14: 0000000000000000 R15: 00007ffd589f40d8 [ 6902.167553] irq event stamp: 0 [ 6902.168998] hardirqs last enabled at (0): [<0000000000000000>] (null) [ 6902.170731] hardirqs last disabled at (0): [] copy_process.part.55+0x3b0/0x1f00 [ 6902.172773] softirqs last enabled at (0): [] copy_process.part.55+0x3b0/0x1f00 [ 6902.174671] softirqs last disabled at (0): [<0000000000000000>] (null) [ 6902.176407] ---[ end trace 463138c2986b275c ]--- [ 6902.177636] BTRFS info (device dm-3): space_info 4 has 273465344 free, is not full [ 6902.179453] BTRFS info (device dm-3): space_info total=276824064, used=4685824, pinned=18446744073708158976, reserved=0, may_use=0, readonly=65536 ^^^ obviously underflow When transaction_kthread is running cleanup_transaction(), another fsstress is running btrfs_commit_transaction(). The btrfs_finish_extent_commit() may get the same range as btrfs_destroy_pinned_extent() got, which causes the pinned underflow. Signed-off-by: Lu Fengqi --- fs/btrfs/disk-io.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index b0ab41da91d1..00ee5e37e989 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -4359,13 +4359,23 @@ static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info, unpin = pinned_extents; again: while (1) { + /* + * The btrfs_finish_extent_commit() may get the same range as + * ours between find_first_extent_bit and clear_extent_dirty. + * Hence, hold the unused_bg_unpin_mutex to avoid double unpin + * the same extent range. + */ + mutex_lock(&fs_info->unused_bg_unpin_mutex); ret = find_first_extent_bit(unpin, 0, &start, &end, EXTENT_DIRTY, NULL); - if (ret) + if (ret) { + mutex_unlock(&fs_info->unused_bg_unpin_mutex); break; + } clear_extent_dirty(unpin, start, end); btrfs_error_unpin_extent_range(fs_info, start, end); + mutex_unlock(&fs_info->unused_bg_unpin_mutex); cond_resched(); }