From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A32EAC433ED for ; Tue, 20 Apr 2021 07:40:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7521F61354 for ; Tue, 20 Apr 2021 07:40:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229793AbhDTHlE (ORCPT ); Tue, 20 Apr 2021 03:41:04 -0400 Received: from smtpout1.mo3005.mail-out.ovh.net ([79.137.123.220]:37431 "EHLO smtpout1.3005.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229583AbhDTHlD (ORCPT ); Tue, 20 Apr 2021 03:41:03 -0400 X-Greylist: delayed 366 seconds by postgrey-1.27 at vger.kernel.org; Tue, 20 Apr 2021 03:41:02 EDT Received: from mxplan5.mail.ovh.net (unknown [10.108.4.144]) by mo3005.mail-out.ovh.net (Postfix) with ESMTPS id 41356141A27; Tue, 20 Apr 2021 07:34:22 +0000 (UTC) Received: from kaod.org (37.59.142.100) by DAG8EX1.mxp5.local (172.16.2.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2242.4; Tue, 20 Apr 2021 09:34:21 +0200 Authentication-Results: garm.ovh; auth=pass (GARM-100R003ff1e15fc-d96d-46c0-9a30-b0f5e4c29b11, F8484F3EE3345E552A9359E6756AA457A7210C68) smtp.auth=groug@kaod.org X-OVh-ClientIp: 78.197.208.248 Date: Tue, 20 Apr 2021 09:34:20 +0200 From: Greg Kurz To: Vivek Goyal CC: , , , , , , , Subject: Re: [Virtio-fs] [PATCH v3 2/3] dax: Add a wakeup mode parameter to put_unlocked_entry() Message-ID: <20210420093420.2eed3939@bahia.lan> In-Reply-To: <20210419213636.1514816-3-vgoyal@redhat.com> References: <20210419213636.1514816-1-vgoyal@redhat.com> <20210419213636.1514816-3-vgoyal@redhat.com> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [37.59.142.100] X-ClientProxiedBy: DAG3EX1.mxp5.local (172.16.2.21) To DAG8EX1.mxp5.local (172.16.2.71) X-Ovh-Tracer-GUID: 895b2bce-2bc7-4d1b-86ac-94b14387f467 X-Ovh-Tracer-Id: 9511039463505303855 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeduledrvddthedguddvfecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfqggfjpdevjffgvefmvefgnecuuegrihhlohhuthemucehtddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpeffhffvuffkjghfofggtgfgihesthejredtredtvdenucfhrhhomhepifhrvghgucfmuhhriicuoehgrhhouhhgsehkrghougdrohhrgheqnecuggftrfgrthhtvghrnhepfedutdeijeejveehkeeileetgfelteekteehtedtieefffevhffflefftdefleejnecukfhppedtrddtrddtrddtpdefjedrheelrddugedvrddutddtnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmohguvgepshhmthhpqdhouhhtpdhhvghlohepmhigphhlrghnhedrmhgrihhlrdhovhhhrdhnvghtpdhinhgvtheptddrtddrtddrtddpmhgrihhlfhhrohhmpehgrhhouhhgsehkrghougdrohhrghdprhgtphhtthhopehvihhrthhiohdqfhhssehrvgguhhgrthdrtghomh Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon, 19 Apr 2021 17:36:35 -0400 Vivek Goyal wrote: > As of now put_unlocked_entry() always wakes up next waiter. In next > patches we want to wake up all waiters at one callsite. Hence, add a > parameter to the function. > > This patch does not introduce any change of behavior. > > Suggested-by: Dan Williams > Signed-off-by: Vivek Goyal > --- > fs/dax.c | 13 +++++++------ > 1 file changed, 7 insertions(+), 6 deletions(-) > > diff --git a/fs/dax.c b/fs/dax.c > index 00978d0838b1..f19d76a6a493 100644 > --- a/fs/dax.c > +++ b/fs/dax.c > @@ -275,11 +275,12 @@ static void wait_entry_unlocked(struct xa_state *xas, void *entry) > finish_wait(wq, &ewait.wait); > } > > -static void put_unlocked_entry(struct xa_state *xas, void *entry) > +static void put_unlocked_entry(struct xa_state *xas, void *entry, > + enum dax_entry_wake_mode mode) > { > /* If we were the only waiter woken, wake the next one */ With this change, the comment is no longer accurate since the function can now wake all waiters if passed mode == WAKE_ALL. Also, it paraphrases the code which is simple enough, so I'd simply drop it. This is minor though and it shouldn't prevent this fix to go forward. Reviewed-by: Greg Kurz > if (entry && !dax_is_conflict(entry)) > - dax_wake_entry(xas, entry, WAKE_NEXT); > + dax_wake_entry(xas, entry, mode); > } > > /* > @@ -633,7 +634,7 @@ struct page *dax_layout_busy_page_range(struct address_space *mapping, > entry = get_unlocked_entry(&xas, 0); > if (entry) > page = dax_busy_page(entry); > - put_unlocked_entry(&xas, entry); > + put_unlocked_entry(&xas, entry, WAKE_NEXT); > if (page) > break; > if (++scanned % XA_CHECK_SCHED) > @@ -675,7 +676,7 @@ static int __dax_invalidate_entry(struct address_space *mapping, > mapping->nrexceptional--; > ret = 1; > out: > - put_unlocked_entry(&xas, entry); > + put_unlocked_entry(&xas, entry, WAKE_NEXT); > xas_unlock_irq(&xas); > return ret; > } > @@ -954,7 +955,7 @@ static int dax_writeback_one(struct xa_state *xas, struct dax_device *dax_dev, > return ret; > > put_unlocked: > - put_unlocked_entry(xas, entry); > + put_unlocked_entry(xas, entry, WAKE_NEXT); > return ret; > } > > @@ -1695,7 +1696,7 @@ dax_insert_pfn_mkwrite(struct vm_fault *vmf, pfn_t pfn, unsigned int order) > /* Did we race with someone splitting entry or so? */ > if (!entry || dax_is_conflict(entry) || > (order == 0 && !dax_is_pte_entry(entry))) { > - put_unlocked_entry(&xas, entry); > + put_unlocked_entry(&xas, entry, WAKE_NEXT); > xas_unlock_irq(&xas); > trace_dax_insert_pfn_mkwrite_no_entry(mapping->host, vmf, > VM_FAULT_NOPAGE);