From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 F40E71A9FB7 for ; Mon, 22 Jun 2026 01:46:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782092789; cv=none; b=QfJC1Jl+qB6wJU3GGYBe+/H4fSUyY/asnEXRH5IPksFpmQ81RidQVkYXsx8TbNaVlq+R2b6Dt2qfQ/Qqz8MUIymomey4pOSev5WyFYAsZygQzTEKhJpBu+nM5h5Xw5kpmTImgRZAqlX5FmS5/P6qPD8+/q5D0Oj+tW6OeVhL4CI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782092789; c=relaxed/simple; bh=xwhNiiW6JjBQk8OsyvaLt5JvF7miSNpXqVIvLONcpE8=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=jRmF6Eb42HVEf1yx2W7oqEihMHW75DDHTEGsVH0SmI/0OXoCzOaeXNZ2ebRNDJbrkYCZ/ywEX+E9TUwkZIPOsSpuyZ85w+9XlS08CnzPwdQjbtjVXpzfY7tA0l1Dg2FKy0rFKOHhqH44OLD/Y5fP1EPSAdzYRAFq/3Qy2a+7JV8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=W77ZZOHB; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="W77ZZOHB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D59AE1F000E9; Mon, 22 Jun 2026 01:46:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782092788; bh=s8d0wK3H8YgUvjSOLhu94Vxjd6l1lGx3XFz9Z10AdaE=; h=Date:Cc:Subject:To:References:From:In-Reply-To; b=W77ZZOHBS8gCVXnJijAIx3wZiwldPoeL5bBzb/7jLyGCbzSWX1pbRC5DN0uGwuesA tDconFwAHlWioK9KHJOcj+7ty7PBSHo5Mo8Lq/BU7ISWMAbjgV+eXFuBOCCP4JJNj0 EdtwCGOh2DN4oNpcwtqBjzrA24N/HA8frrBsBbSzQqbk0tVtB3BT5IsxB8zVvwlhhF 9VnNL/1gAxTSO/fMKRGNxKfoC4Xt7v88W+lBkwQVlfad/5eVcNgUH05aasdMI+HJb1 a/tpeUFXVBThcokXb1gCukv4Q+ESqcLzjOp4xnM6xLOomyBFlYr8pcsDQERoPsD+6j dyEXnOAr1NSug== Message-ID: Date: Mon, 22 Jun 2026 09:46:24 +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 Cc: chao@kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, jianxin.pan@amlogic.com, tuan.zhang@amlogic.com Subject: Re: [PATCH] f2fs: fix FG GC failure when file in victim is pinned To: jiucheng.xu@amlogic.com, Jaegeuk Kim References: <20260620-origin-dev-v1-1-3b2e639e794c@amlogic.com> Content-Language: en-US From: Chao Yu In-Reply-To: <20260620-origin-dev-v1-1-3b2e639e794c@amlogic.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 6/20/26 17:34, Jiucheng Xu via B4 Relay wrote: > From: Jiucheng Xu > > When continuous write operations occur in the system, BG GC fails to > work. This leads to large dirty_segments and small free_segments. If > fallocate() is performed on a pinned file with the allocated space > exceeding the free_segment, FG_GC reclamation fails. > > The reason is that the file corresponding to the block in the victim is > pinned, causing gc_data_segment() to fail. Since the condition sec_freed Jiucheng, pinned file should be aligned to section size, why there is fragmented blocks of pinfile locates in dirty sections? > < gc_control->nr_free_secs isn't satisfied, GC stops, resulting in the > failure of f2fs_fallocate() allocation. > > Setting gc_control->nr_free_secs = 1 make FG GC continue searching > for new victim. Maybe we can try this instead of changing f2fs_expand_inode_data() logic: 1. call fggc via ioctl or trigger urgent gc via sysfs 2. fallocate on pinfile, goto 1) if it failed But, anyway, I suspect it's risk, if there is no normal dirty section, FGGC will try to call f2fs_unpin_all_sections(), then migrate dirty section which has pinned blocks, that will cause more damage. Can you please figure out why pinfile is fragmented first... Thanks, > > Signed-off-by: Jiucheng Xu > --- > fs/f2fs/file.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > index 8acdd94272a0ced448e0ba21635d702cfec10682..3e49a73bbf3a184a314e97bff9509a66c27eac00 100644 > --- a/fs/f2fs/file.c > +++ b/fs/f2fs/file.c > @@ -1883,7 +1883,7 @@ static int f2fs_expand_inode_data(struct inode *inode, loff_t offset, > .init_gc_type = FG_GC, > .should_migrate_blocks = false, > .err_gc_skipped = true, > - .nr_free_secs = 0 }; > + .nr_free_secs = 1 }; > pgoff_t pg_start, pg_end; > loff_t new_size; > loff_t off_end; > > --- > base-commit: b51f606aa323d553d786ed681a213f134dc688d6 > change-id: 20260620-origin-dev-99cdccc83800 > > Best regards,