From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-99.freemail.mail.aliyun.com (out30-99.freemail.mail.aliyun.com [115.124.30.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 535F23B9DBE for ; Wed, 1 Apr 2026 09:47:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.99 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775036828; cv=none; b=ITR4utN77y827UZv/VB9fhEyySexG/sklhFuw5Hkwqm9Iwg1UJhOubUlRpjSlEUOW7B5wTmdCWufNrUgA8fJdqjPY2k0+4gVYEw5DJ3TPq+GFlKE2EZQSn3g0sOQ3brT4S6dUr3otZDlYojK+MR/AyfmMsb6/jiHb73XWRuwVYQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775036828; c=relaxed/simple; bh=jbnVPqgOBxkzR85fGJcd5D5HUYJKtaN+tzUcmNvGrlI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=NEuA2oS4L/GwFgTyrrS3xiaYLAILvllFHEUOkMyRTaxZBq80fk3IOevL1tYIY0vhdER1Ql/Jbb+3tCP4H+L2b2BlqcQhKg6Hl5jfOAd8N+5epwj2f2qL3kiv3gQ1VXVwIGcvqtK5FRvFohejntX1+/2Pp/wkm8v8iIidQuxTrDo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=LZzsxToq; arc=none smtp.client-ip=115.124.30.99 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="LZzsxToq" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1775036817; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=CWFdaIyXXKYubFcZtyFhugP8NDVvB5eJ08IFrFOVnUg=; b=LZzsxToqeKxmqI/hB47fM+QNQ3BdHjtyDFNmxxwoiMCyySN3yS0FCFAzM0tg9uaRJAb0lVrjoBgJTilWvInLoCEXkHsEZyAVZPlSftVHufuyN1UOCud07K51sPjhFhnaVXnKIsvu/HRE+n1Q/ikvVImetHx0SvXdFTPIXOAOHsw= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R151e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033032089153;MF=joseph.qi@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0X0AXFBq_1775036816; Received: from 30.221.145.27(mailfrom:joseph.qi@linux.alibaba.com fp:SMTPD_---0X0AXFBq_1775036816 cluster:ay36) by smtp.aliyun-inc.com; Wed, 01 Apr 2026 17:46:56 +0800 Message-ID: <2501759b-1a26-4ea8-b17d-d2f4b8c96ac9@linux.alibaba.com> Date: Wed, 1 Apr 2026 17:46:56 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 1/1] ocfs2: split transactions in dio completion to avoid credit exhaustion To: Heming Zhao Cc: ocfs2-devel@lists.linux.dev, linux-kernel@vger.kernel.org, glass.su@suse.com, Jan Kara References: <20260327063626.10225-1-heming.zhao@suse.com> <20260327063626.10225-2-heming.zhao@suse.com> From: Joseph Qi In-Reply-To: <20260327063626.10225-2-heming.zhao@suse.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/27/26 2:36 PM, Heming Zhao wrote: > During ocfs2 dio operations, JBD2 may report warnings via following call trace: > ocfs2_dio_end_io_write > ocfs2_mark_extent_written > ocfs2_change_extent_flag > ocfs2_split_extent > ocfs2_try_to_merge_extent > ocfs2_extend_rotate_transaction > ocfs2_extend_trans > jbd2__journal_restart > start_this_handle > output: JBD2: kworker/6:2 wants too many credits credits:5450 rsv_credits:0 max:5449 > > To prevent exceeding the credits limit, modify ocfs2_dio_end_io_write() to > handle extents in a batch of transaction. > > Additionally, relocate ocfs2_del_inode_from_orphan(). The orphan inode should > only be removed from the orphan list after the extent tree update is complete. > This ensures that if a crash occurs in the middle of extent tree updates, we > won't leave stale blocks beyond EOF. > > This patch also changes the logic for updating the inode size and removing > orphan, making it similar to ext4_dio_write_end_io(). Both operations are > performed only when everything looks good. > > Finally, thanks to Jans and Joseph for providing the bug fix prototype and > suggestions. > > Suggested-by: Jan Kara > Suggested-by: Joseph Qi > Reviewed-by: Jan Kara > Signed-off-by: Heming Zhao > --- > fs/ocfs2/aops.c | 63 +++++++++++++++++++++++++++---------------------- > 1 file changed, 35 insertions(+), 28 deletions(-) > > diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c > index 09146b43d1f0..a542cd0a6f75 100644 > --- a/fs/ocfs2/aops.c > +++ b/fs/ocfs2/aops.c > @@ -37,6 +37,8 @@ > #include "namei.h" > #include "sysfile.h" > > +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 > + > static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, > struct buffer_head *bh_result, int create) > { > @@ -2277,7 +2279,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, > struct ocfs2_alloc_context *meta_ac = NULL; > handle_t *handle = NULL; > loff_t end = offset + bytes; > - int ret = 0, credits = 0; > + int ret = 0, credits = 0, batch = 0; > > ocfs2_init_dealloc_ctxt(&dealloc); > > @@ -2294,18 +2296,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, > goto out; > } > > - /* Delete orphan before acquire i_rwsem. */ > - if (dwc->dw_orphaned) { > - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); > - > - end = end > i_size_read(inode) ? end : 0; > - > - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, > - !!end, end); > - if (ret < 0) > - mlog_errno(ret); > - } > - > down_write(&oi->ip_alloc_sem); > di = (struct ocfs2_dinode *)di_bh->b_data; > > @@ -2326,24 +2316,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, > > credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); > > - handle = ocfs2_start_trans(osb, credits); > - if (IS_ERR(handle)) { > - ret = PTR_ERR(handle); > - mlog_errno(ret); > - goto unlock; > - } > - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, > - OCFS2_JOURNAL_ACCESS_WRITE); > - if (ret) { > - mlog_errno(ret); > - goto commit; > - } > - > list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { > + if (!handle) { > + handle = ocfs2_start_trans(osb, credits); > + if (IS_ERR(handle)) { > + ret = PTR_ERR(handle); > + mlog_errno(ret); > + goto unlock; > + } > + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, > + OCFS2_JOURNAL_ACCESS_WRITE); > + if (ret) { > + mlog_errno(ret); > + goto commit; > + } > + } > ret = ocfs2_assure_trans_credits(handle, credits); > if (ret < 0) { > mlog_errno(ret); > - break; > + goto commit; > } > ret = ocfs2_mark_extent_written(inode, &et, handle, > ue->ue_cpos, 1, > @@ -2351,7 +2342,13 @@ static int ocfs2_dio_end_io_write(struct inode *inode, > meta_ac, &dealloc); > if (ret < 0) { > mlog_errno(ret); > - break; > + goto commit; > + } > + > + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { > + ocfs2_commit_trans(osb, handle); > + handle = NULL; > + batch = 0; > } > } > > @@ -2360,10 +2357,20 @@ static int ocfs2_dio_end_io_write(struct inode *inode, > if (ret < 0) > mlog_errno(ret); > } > + > commit: > ocfs2_commit_trans(osb, handle); We have to check 'handle' here to prevent NULL pointer dereference. e.g. rightly after OCFS2_DIO_MARK_EXTENT_BATCH round. And you've missed ocfs2_start_trans() and ocfs2_journal_access_di() before ocfs2_set_inode_size(). Thanks, Joseph > unlock: > up_write(&oi->ip_alloc_sem); > + > + /* everything looks good, let's start the cleanup */ > + if (!ret && dwc->dw_orphaned) { > + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); > + > + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); > + if (ret < 0) > + mlog_errno(ret); > + } > ocfs2_inode_unlock(inode, 1); > brelse(di_bh); > out: