From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailout2.samsung.com (mailout2.samsung.com [203.254.224.25]) (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 D372A3081C1 for ; Mon, 22 Sep 2025 12:51:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=203.254.224.25 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758545502; cv=none; b=Bh2BqRjUrbyEHGWHMgV1Jfdw5BEPUTt2K2Q419BeuNjEbRI5AQnYsuxsUZKDgv/04IDpMdWxbnmBkQV49vaT5p5Cj3RWPKW7ertAQnRvodsonvYCLr/yz2Yftj+LQOUyb5wPcuJ9GqcOGg1JCONamFgWajBqIz2dYAvSZtrr1K4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758545502; c=relaxed/simple; bh=ZQ5VUijvYpFvcyKNThwBlQAIlb7oH7NFolfh4z9Dr98=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:In-Reply-To: Content-Type:References; b=LxqISIs6T6N9loTIfH4Ki+++YkAQs5ECiqtfRn24Y7ul3jqeSeITn+YTPhTx6feCXJnx1ZotWzuFnmLsjaGR5M8+3fp/W6A7UGeFD7cVoXAERgr1pTcRYrYExJ6muLnHHf+J9AkrA6Bajf2Wxnk64Ua9ItoA0DpNYo7H0K9Y2EA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com; spf=pass smtp.mailfrom=samsung.com; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b=AX0tZCik; arc=none smtp.client-ip=203.254.224.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=samsung.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b="AX0tZCik" Received: from epcas5p4.samsung.com (unknown [182.195.41.42]) by mailout2.samsung.com (KnoxPortal) with ESMTP id 20250922125137epoutp023fe0521c6fe1cfb63fb121e2d34aa91d~nm9AfQvma3199931999epoutp02h for ; Mon, 22 Sep 2025 12:51:37 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout2.samsung.com 20250922125137epoutp023fe0521c6fe1cfb63fb121e2d34aa91d~nm9AfQvma3199931999epoutp02h DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1758545497; bh=HYKpfIouK921vQ6QGHevYxod5Jzj4y8Z8mu37Q92pkQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=AX0tZCik32940iGDLI1f49OSHAKkS2a5SUJ3wFKhIIa3Jv/io1GR2nT2sN4xtJbT7 dPS0FAlhERk5PoYMP45zSHyuPlkArcCeB71/nFEpxcpOiqloTwUmLrMLJzHXMf8JgK rdbxW7wDrW/aJ6aCijLvwln+2kDNxVclVUvsOcRY= Received: from epsnrtp04.localdomain (unknown [182.195.42.156]) by epcas5p3.samsung.com (KnoxPortal) with ESMTPS id 20250922125137epcas5p33b1bb74798ea240fe00b72dd28bdb560~nm9AQ_CM41720517205epcas5p3k; Mon, 22 Sep 2025 12:51:37 +0000 (GMT) Received: from epcas5p1.samsung.com (unknown [182.195.38.88]) by epsnrtp04.localdomain (Postfix) with ESMTP id 4cVjfc3V7Xz6B9m5; Mon, 22 Sep 2025 12:51:36 +0000 (GMT) Received: from epsmtip1.samsung.com (unknown [182.195.34.30]) by epcas5p3.samsung.com (KnoxPortal) with ESMTPA id 20250922125135epcas5p3ac2131266f68cc18eaed3921a42bdf9b~nm8_pSBu81431814318epcas5p3u; Mon, 22 Sep 2025 12:51:35 +0000 (GMT) Received: from test-PowerEdge-R740xd (unknown [107.99.41.79]) by epsmtip1.samsung.com (KnoxPortal) with ESMTPA id 20250922125134epsmtip1cbbc4d374f9f2829a520f3f1670c2f7c~nm89m51rS0171401714epsmtip1K; Mon, 22 Sep 2025 12:51:34 +0000 (GMT) Date: Mon, 22 Sep 2025 18:21:25 +0530 From: Neeraj Kumar To: Jonathan Cameron Cc: linux-cxl@vger.kernel.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, gost.dev@samsung.com, a.manzanares@samsung.com, vishak.g@samsung.com, neeraj.kernel@gmail.com Subject: Re: [PATCH V3 04/20] nvdimm/label: Update mutex_lock() with guard(mutex)() Message-ID: <20250922125125.tm3yapxoxd5lhmat@test-PowerEdge-R740xd> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <20250917154656.00001c2f@huawei.com> X-CMS-MailID: 20250922125135epcas5p3ac2131266f68cc18eaed3921a42bdf9b X-Msg-Generator: CA Content-Type: multipart/mixed; boundary="-----ZxWg4Xdj5J3Rn97nhBblfMsRvMrJ.qI_ZCg1wtmDaptzyAW=_26db1_" CMS-TYPE: 105P cpgsPolicy: CPGSC10-542,Y X-CFilter-Loop: Reflected X-CMS-RootMailID: 20250917133034epcas5p2c9485e40fce4c3a5a826cc94d515b25d References: <20250917132940.1566437-1-s.neeraj@samsung.com> <20250917132940.1566437-5-s.neeraj@samsung.com> <20250917154656.00001c2f@huawei.com> -------ZxWg4Xdj5J3Rn97nhBblfMsRvMrJ.qI_ZCg1wtmDaptzyAW=_26db1_ Content-Type: text/plain; charset="utf-8"; format="flowed" Content-Disposition: inline On 17/09/25 03:46PM, Jonathan Cameron wrote: >On Wed, 17 Sep 2025 18:59:24 +0530 >Neeraj Kumar wrote: > >> Updated mutex_lock() with guard(mutex)() > >Say why. Sure, I will update it in next patch-set. >> >> Signed-off-by: Neeraj Kumar >> --- >> drivers/nvdimm/label.c | 36 +++++++++++++++++------------------- >> 1 file changed, 17 insertions(+), 19 deletions(-) >> >> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c >> index 668e1e146229..3235562d0e1c 100644 >> --- a/drivers/nvdimm/label.c >> +++ b/drivers/nvdimm/label.c >> @@ -948,7 +948,7 @@ static int __pmem_label_update(struct nd_region *nd_region, >> return rc; >> + list_for_each_entry(label_ent, &nd_mapping->labels, list) >> + if (!label_ent->label) { >> + label_ent->label = nd_label; >> + nd_label = NULL; >> + break; > >Perhaps it will change in later patches, but you could have done > if (!label_ent->label) { > label_ent->label = nd_label; > return; > } >as nothing else happens if we find a match. Yes, I have updated it in later patch. I will update it here itself. > >> + } >> @@ -998,9 +998,8 @@ static int init_labels(struct nd_mapping *nd_mapping, int num_labels) >> label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL); >> if (!label_ent) >> return -ENOMEM; >> - mutex_lock(&nd_mapping->lock); >> + guard(mutex)(&nd_mapping->lock); >> list_add_tail(&label_ent->list, &nd_mapping->labels); >> - mutex_unlock(&nd_mapping->lock); > >Not sure I'd bother with cases like this but harmless. > >> } >> >> - mutex_lock(&nd_mapping->lock); >> + guard(mutex)(&nd_mapping->lock); >> list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) { >> struct nd_namespace_label *nd_label = label_ent->label; >> >> @@ -1061,7 +1060,6 @@ static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid) >> nd_mapping_free_labels(nd_mapping); >> dev_dbg(ndd->dev, "no more active labels\n"); >> } >> - mutex_unlock(&nd_mapping->lock); >This is a potential functional change as the lock is held for longer than before. >nd_label_write_index is not trivial so reviewing if that is safe is not trivial. > >The benefit is small so far (maybe that changes in later patches) so I would not >make the change. Sure, I will revert it back in next patch-set Regards, Neeraj > > > >> >> return nd_label_write_index(ndd, ndd->ns_next, >> nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0); > -------ZxWg4Xdj5J3Rn97nhBblfMsRvMrJ.qI_ZCg1wtmDaptzyAW=_26db1_ Content-Type: text/plain; charset="utf-8" -------ZxWg4Xdj5J3Rn97nhBblfMsRvMrJ.qI_ZCg1wtmDaptzyAW=_26db1_--