From patchwork Mon Dec 6 12:29:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirill A. Shutemov" X-Patchwork-Id: 521652 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CCC6FC433F5 for ; Mon, 6 Dec 2021 12:30:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243162AbhLFMdr (ORCPT ); Mon, 6 Dec 2021 07:33:47 -0500 Received: from mga06.intel.com ([134.134.136.31]:5275 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243180AbhLFMdr (ORCPT ); Mon, 6 Dec 2021 07:33:47 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10189"; a="298101829" X-IronPort-AV: E=Sophos;i="5.87,291,1631602800"; d="scan'208";a="298101829" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Dec 2021 04:30:18 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,291,1631602800"; d="scan'208";a="562759884" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga008.fm.intel.com with ESMTP; 06 Dec 2021 04:30:01 -0800 Received: by black.fi.intel.com (Postfix, from userid 1000) id 6F2D7199; Mon, 6 Dec 2021 14:30:07 +0200 (EET) From: "Kirill A. Shutemov" To: rafael@kernel.org Cc: ak@linux.intel.com, bp@alien8.de, dan.j.williams@intel.com, dave.hansen@linux.intel.com, hpa@zytor.com, kirill.shutemov@linux.intel.com, knsathya@kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, rjw@rjwysocki.net, sathyanarayanan.kuppuswamy@linux.intel.com, tglx@linutronix.de, tony.luck@intel.com, x86@kernel.org Subject: [PATCH 2/4] ACPI: PM: Remove redundant cache flushing Date: Mon, 6 Dec 2021 15:29:50 +0300 Message-Id: <20211206122952.74139-3-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211206122952.74139-1-kirill.shutemov@linux.intel.com> References: <20211206122952.74139-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org ACPICA code takes care about cache flushing on S1/S2/S3 in acpi_hw_extended_sleep() and acpi_hw_legacy_sleep(). acpi_suspend_enter() calls into ACPICA code via acpi_enter_sleep_state() for S1 or x86_acpi_suspend_lowlevel() for S3. It only need to flush cache for S2 (not sure if this call path is ever used for S2). acpi_sleep_prepare() call tree: __acpi_pm_prepare() acpi_pm_prepare() acpi_suspend_ops::prepare_late() acpi_hibernation_ops::pre_snapshot() acpi_hibernation_ops::prepare() acpi_suspend_begin_old() acpi_suspend_begin_old::begin() acpi_hibernation_begin_old() acpi_hibernation_ops_old::acpi_hibernation_begin_old() acpi_power_off_prepare() pm_power_off_prepare() Hibernation (S4) and Power Off (S5) don't require cache flushing. So, the only interesting callsites are acpi_suspend_ops::prepare_late() and acpi_suspend_begin_old::begin(). Both of them have cache flush on ->enter() operation in acpi_suspend_enter(). Remove redundant ACPI_FLUSH_CPU_CACHE() in acpi_sleep_prepare() and acpi_suspend_enter(). Signed-off-by: Kirill A. Shutemov --- drivers/acpi/sleep.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c index eaa47753b758..14e8df0ac762 100644 --- a/drivers/acpi/sleep.c +++ b/drivers/acpi/sleep.c @@ -73,7 +73,6 @@ static int acpi_sleep_prepare(u32 acpi_state) acpi_set_waking_vector(acpi_wakeup_address); } - ACPI_FLUSH_CPU_CACHE(); #endif pr_info("Preparing to enter system sleep state S%d\n", acpi_state); acpi_enable_wakeup_devices(acpi_state); @@ -566,15 +565,15 @@ static int acpi_suspend_enter(suspend_state_t pm_state) u32 acpi_state = acpi_target_sleep_state; int error; - ACPI_FLUSH_CPU_CACHE(); - trace_suspend_resume(TPS("acpi_suspend"), acpi_state, true); switch (acpi_state) { case ACPI_STATE_S1: barrier(); status = acpi_enter_sleep_state(acpi_state); break; - + case ACPI_STATE_S2: + ACPI_FLUSH_CPU_CACHE(); + break; case ACPI_STATE_S3: if (!acpi_suspend_lowlevel) return -ENOSYS;