From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 83F7E3BD254 for ; Tue, 17 Mar 2026 12:13:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773749594; cv=none; b=HQUyMbcHHQbuLxelYcY0JlPWsvqrPb1nB62WmEXzVh0poEhAeCUYhedJcSEZaR6P5G3VxJZJWWrgwe6zmrEHmOg4cceP0Q8H2uFl77NDf3US38U87XXKQaWZaF6Pge3KFShngPb36OiouDFq+sSaVDW0VZfz+dDPAfeFxXD1OOc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773749594; c=relaxed/simple; bh=j2+gMezO+EJHDjOx4g6mDUGFKpIz1DGOvMaSdGa/Xn0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ApYp7SywEcAjPH1+1NOr6DbWt6KQnNeZPhLaeYGuf8sPw3rzSrNwbY0lJnQ7oZj1clPgAsjUoF/d3Vqv5azIH4SarfgTurUkHRfS4LkIgkiA9MxrsOkkDL8KNujZmcfrnOlRpWN+z9e4mFJ/QwWKEnHT2j1+C+yqzKwQSy9sKhk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=ZwGtneSF; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ZwGtneSF" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1773749592; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=xjElnualtUEiUWiSmPb+BX2Xj9BtdgYxsyYH/MUOdBs=; b=ZwGtneSF63WhDSYMAT+rMlzDYSUSDTKI6iPEirzayTD94gzuVbK45124yxdoehxLBOlOrA pj3/odqycJ4uluBIkGMFRDQ+1eOedvgTvSfr8gVrc4JmO34X9+XkbB2dYRoGd++GSNL2yd 22Gw0WT5vphWCqeoypKmAN9TtfsJyTc= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-645-U5RxsatIMdSK9L7pK0KPRw-1; Tue, 17 Mar 2026 08:13:09 -0400 X-MC-Unique: U5RxsatIMdSK9L7pK0KPRw-1 X-Mimecast-MFC-AGG-ID: U5RxsatIMdSK9L7pK0KPRw_1773749588 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 4439A1800281; Tue, 17 Mar 2026 12:13:08 +0000 (UTC) Received: from bfoster (unknown [10.22.89.178]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 755B53000223; Tue, 17 Mar 2026 12:13:07 +0000 (UTC) Date: Tue, 17 Mar 2026 08:13:04 -0400 From: Brian Foster To: Christoph Hellwig Cc: Carlos Maiolino , Dave Chinner , linux-xfs@vger.kernel.org Subject: Re: buffer cache simplification v4 Message-ID: References: <20260316154216.1598410-1-hch@lst.de> Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260316154216.1598410-1-hch@lst.de> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 On Mon, Mar 16, 2026 at 04:41:32PM +0100, Christoph Hellwig wrote: > Hi all, > > this series has a few old patches that simplify the LRU handling, and > moves back to only having a per-buftarg hash now that the buffer hash > is using the scalable rhashtable. While some of this looks like > performance work, performance and scalability is unchanged even on the > 80 core dual socket system I test this on. Besides cleaning up the > code nice, it also happens to fix a syzcaller reported use after free > during buffer shutdown, which happened incidentally because of how the > tear down of the buftarg vs the perag structures is handled. > > Changes since v3: > - split the change to handling how referenced buffers on the LRU > are handled into a separate patch > It looks like there's a patch ordering problem or something here. It doesn't apply to master, and looks like patch 1 is trying to modify hunks that don't yet exist. A local rebase issue related to reordering the change in patch 3 perhaps..? Brian > Changes since v2: > - mark b_hold as signed in patch 1 before removing it in patch 2 > - document the changed locking in xfs_buf_rele_cached. > > Changes since v2: > - add more details and a link to a commit message > > Diffstat: > libxfs/xfs_ag.c | 13 ---- > libxfs/xfs_ag.h | 2 > xfs_buf.c | 148 ++++++++++++++++++++------------------------------------ > xfs_buf.h | 14 +---- > xfs_buf_mem.c | 11 ---- > xfs_trace.h | 10 +-- > 6 files changed, 66 insertions(+), 132 deletions(-) >