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=-11.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 B2C32C3A59B for ; Mon, 19 Aug 2019 08:56:50 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E75CD2184E for ; Mon, 19 Aug 2019 08:56:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E75CD2184E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=rjwysocki.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 46Bnq35zJCzDqvR for ; Mon, 19 Aug 2019 18:56:47 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=rjwysocki.net (client-ip=79.96.170.134; helo=cloudserver094114.home.pl; envelope-from=rjw@rjwysocki.net; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=rjwysocki.net Received: from cloudserver094114.home.pl (cloudserver094114.home.pl [79.96.170.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 46Bnmp6xg6zDqhT for ; Mon, 19 Aug 2019 18:54:49 +1000 (AEST) Received: from 79.184.254.79.ipv4.supernova.orange.pl (79.184.254.79) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.275) id dd98f88ef098e161; Mon, 19 Aug 2019 10:54:44 +0200 From: "Rafael J. Wysocki" To: Ran Wang Subject: Re: [PATCH v5 1/3] PM: wakeup: Add routine to help fetch wakeup source object. Date: Mon, 19 Aug 2019 10:54:43 +0200 Message-ID: <2529818.3AUhDYJ4cv@kreacher> In-Reply-To: References: <20190724074722.12270-1-ran.wang_1@nxp.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Biwen Li , Len Brown , "Rafael J. Wysocki" , Greg Kroah-Hartman , "linux-pm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Leo Li , "devicetree@vger.kernel.org" , Rob Herring , Pavel Machek , "linuxppc-dev@lists.ozlabs.org" , "linux-arm-kernel@lists.infradead.org" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Monday, August 19, 2019 10:33:25 AM CEST Ran Wang wrote: > Hi Rafael, > > On Monday, August 19, 2019 16:20, Rafael J. Wysocki wrote: > > > > On Mon, Aug 19, 2019 at 10:15 AM Ran Wang wrote: > > > > > > Hi Rafael, > > > > > > On Monday, August 05, 2019 17:59, Rafael J. Wysocki wrote: > > > > > > > > On Wednesday, July 24, 2019 9:47:20 AM CEST Ran Wang wrote: > > > > > Some user might want to go through all registered wakeup sources > > > > > and doing things accordingly. For example, SoC PM driver might > > > > > need to do HW programming to prevent powering down specific IP > > > > > which wakeup source depending on. So add this API to help walk > > > > > through all registered wakeup source objects on that list and return them > > one by one. > > > > > > > > > > Signed-off-by: Ran Wang > > > > > --- > > > > > Change in v5: > > > > > - Update commit message, add decription of walk through all wakeup > > > > > source objects. > > > > > - Add SCU protection in function wakeup_source_get_next(). > > > > > - Rename wakeup_source member 'attached_dev' to 'dev' and move > > > > > it > > > > up > > > > > (before wakeirq). > > > > > > > > > > Change in v4: > > > > > - None. > > > > > > > > > > Change in v3: > > > > > - Adjust indentation of *attached_dev;. > > > > > > > > > > Change in v2: > > > > > - None. > > > > > > > > > > drivers/base/power/wakeup.c | 24 ++++++++++++++++++++++++ > > > > > include/linux/pm_wakeup.h | 3 +++ > > > > > 2 files changed, 27 insertions(+) > > > > > > > > > > diff --git a/drivers/base/power/wakeup.c > > > > > b/drivers/base/power/wakeup.c index ee31d4f..2fba891 100644 > > > > > --- a/drivers/base/power/wakeup.c > > > > > +++ b/drivers/base/power/wakeup.c > > > > > @@ -14,6 +14,7 @@ > > > > > #include > > > > > #include > > > > > #include > > > > > +#include > > > > > #include > > > > > #include > > > > > > > > > > @@ -226,6 +227,28 @@ void wakeup_source_unregister(struct > > > > wakeup_source *ws) > > > > > } > > > > > } > > > > > EXPORT_SYMBOL_GPL(wakeup_source_unregister); > > > > > +/** > > > > > + * wakeup_source_get_next - Get next wakeup source from the list > > > > > + * @ws: Previous wakeup source object, null means caller want first one. > > > > > + */ > > > > > +struct wakeup_source *wakeup_source_get_next(struct wakeup_source > > > > > +*ws) { > > > > > + struct list_head *ws_head = &wakeup_sources; > > > > > + struct wakeup_source *next_ws = NULL; > > > > > + int idx; > > > > > + > > > > > + idx = srcu_read_lock(&wakeup_srcu); > > > > > + if (ws) > > > > > + next_ws = list_next_or_null_rcu(ws_head, &ws->entry, > > > > > + struct wakeup_source, entry); > > > > > + else > > > > > + next_ws = list_entry_rcu(ws_head->next, > > > > > + struct wakeup_source, entry); > > > > > + srcu_read_unlock(&wakeup_srcu, idx); > > > > > + > > > > > > > > This is incorrect. > > > > > > > > The SRCU cannot be unlocked until the caller of this is done with > > > > the object returned by it, or that object can be freed while it is still being > > accessed. > > > > > > Thanks for the comment. Looks like I was not fully understanding your > > > point on > > > v4 discussion. So I will implement 3 APIs by referring > > > wakeup_sources_stats_seq_start/next/stop() > > > > > > > Besides, this patch conflicts with some general wakeup sources > > > > changes in the works, so it needs to be deferred and rebased on top of those > > changes. > > > > > > Could you please tell me which is the right code base I should developing on? > > > I just tried applying v5 patch on latest > > > git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git branch master > > (d1abaeb Linux 5.3-rc5) and no conflict encountered. > > > > It is better to use the most recent -rc from Linus (5.3-rc5 as of > > today) as the base unless your patches depend on some changes that are not in > > there. > > OK, So I need to implement on latest git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git branch master, am I right? > > However, I just checked v5.3-rc5 code and found it has the same HEAD (d1abaeb Linux 5.3-rc5 > on which I did not observe v5 patch apply conflict, did I miss something? Thanks. The conflict I mentioned earlier was with another patch series in the works which is not in 5.3-rc5. However, there are problems with that series and it is not linux-next now even, so please just base your series on top of -rc5.