From patchwork Mon Dec 28 12:48:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 354464 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT 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 50C5EC4332E for ; Mon, 28 Dec 2020 15:59:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2000E22BE8 for ; Mon, 28 Dec 2020 15:59:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387837AbgL1NdB (ORCPT ); Mon, 28 Dec 2020 08:33:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:59260 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390312AbgL1NaX (ORCPT ); Mon, 28 Dec 2020 08:30:23 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 24F2E2063A; Mon, 28 Dec 2020 13:29:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609162182; bh=eEBUkreNbxeJtlMy7/o495At/IUofxpXENnKGBKLzZE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tEmaZeHsXLimRIV/A5oBmCwKb35reqYcgTFuvVZ2w0hlSblHJd0w+tdz86tEjrH9b X2yaCEEYq3DDNOAvu0+fWTqHKg8S97jQZdytN9PeJGsL0uFgq6BO1e4kAfK0hyWJiP HVjvjHm68hYxeWXvKaFREQ0LeJVBVfRA3DVt3X7g= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nathan Lynch , Michael Ellerman , Sasha Levin Subject: [PATCH 4.19 214/346] powerpc/pseries/hibernation: drop pseries_suspend_begin() from suspend ops Date: Mon, 28 Dec 2020 13:48:53 +0100 Message-Id: <20201228124930.124643958@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228124919.745526410@linuxfoundation.org> References: <20201228124919.745526410@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Nathan Lynch [ Upstream commit 52719fce3f4c7a8ac9eaa191e8d75a697f9fbcbc ] There are three ways pseries_suspend_begin() can be reached: 1. When "mem" is written to /sys/power/state: kobj_attr_store() -> state_store() -> pm_suspend() -> suspend_devices_and_enter() -> pseries_suspend_begin() This never works because there is no way to supply a valid stream id using this interface, and H_VASI_STATE is called with a stream id of zero. So this call path is useless at best. 2. When a stream id is written to /sys/devices/system/power/hibernate. pseries_suspend_begin() is polled directly from store_hibernate() until the stream is in the "Suspending" state (i.e. the platform is ready for the OS to suspend execution): dev_attr_store() -> store_hibernate() -> pseries_suspend_begin() 3. When a stream id is written to /sys/devices/system/power/hibernate (continued). After #2, pseries_suspend_begin() is called once again from the pm core: dev_attr_store() -> store_hibernate() -> pm_suspend() -> suspend_devices_and_enter() -> pseries_suspend_begin() This is redundant because the VASI suspend state is already known to be Suspending. The begin() callback of platform_suspend_ops is optional, so we can simply remove that assignment with no loss of function. Fixes: 32d8ad4e621d ("powerpc/pseries: Partition hibernation support") Signed-off-by: Nathan Lynch Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20201207215200.1785968-18-nathanl@linux.ibm.com Signed-off-by: Sasha Levin --- arch/powerpc/platforms/pseries/suspend.c | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/powerpc/platforms/pseries/suspend.c b/arch/powerpc/platforms/pseries/suspend.c index 52a021e1f86bf..fd2c090681aa6 100644 --- a/arch/powerpc/platforms/pseries/suspend.c +++ b/arch/powerpc/platforms/pseries/suspend.c @@ -223,7 +223,6 @@ static struct bus_type suspend_subsys = { static const struct platform_suspend_ops pseries_suspend_ops = { .valid = suspend_valid_only_mem, - .begin = pseries_suspend_begin, .prepare_late = pseries_prepare_late, .enter = pseries_suspend_enter, };