From patchwork Mon Sep 23 23:17:56 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Pitre X-Patchwork-Id: 2931041 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id ED5119F2B8 for ; Mon, 23 Sep 2013 23:51:43 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 26127201F9 for ; Mon, 23 Sep 2013 23:51:43 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2C530201A4 for ; Mon, 23 Sep 2013 23:51:42 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VOFRL-0002vD-D5; Mon, 23 Sep 2013 23:21:16 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VOFQS-0006C1-Lp; Mon, 23 Sep 2013 23:20:20 +0000 Received: from relais.videotron.ca ([24.201.245.36]) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VOFP5-0005wj-KI for linux-arm-kernel@lists.infradead.org; Mon, 23 Sep 2013 23:18:57 +0000 Received: from yoda.home ([70.83.209.44]) by VL-VM-MR005.ip.videotron.ca (Oracle Communications Messaging Exchange Server 7u4-22.01 64bit (built Apr 21 2011)) with ESMTP id <0MTL003BDQ22N190@VL-VM-MR005.ip.videotron.ca> for linux-arm-kernel@lists.infradead.org; Mon, 23 Sep 2013 19:18:02 -0400 (EDT) Received: from xanadu.home (xanadu.home [192.168.2.2]) by yoda.home (Postfix) with ESMTP id 0761F2DA066C; Mon, 23 Sep 2013 19:18:02 -0400 (EDT) From: Nicolas Pitre To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 13/13] ARM: bL_switcher: Add query interface to discover CPU affinities Date: Mon, 23 Sep 2013 19:17:56 -0400 Message-id: <1379978276-31241-14-git-send-email-nicolas.pitre@linaro.org> X-Mailer: git-send-email 1.8.4.98.gb022869 In-reply-to: <1379978276-31241-1-git-send-email-nicolas.pitre@linaro.org> References: <1379978276-31241-1-git-send-email-nicolas.pitre@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130923_191855_767117_85F548B0 X-CRM114-Status: GOOD ( 14.72 ) X-Spam-Score: -1.9 (-) Cc: linaro-kernel@lists.linaro.org, dave.martin@arm.com, patches@linaro.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-6.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Dave Martin When the switcher is active, there is no straightforward way to figure out which logical CPU a given physical CPU maps to. This patch provides a function bL_switcher_get_logical_index(mpidr), which is analogous to get_logical_index(). This function returns the logical CPU on which the specified physical CPU is grouped (or -EINVAL if unknown). If the switcher is inactive or not present, -EUNATCH is returned instead. Signed-off-by: Dave Martin Signed-off-by: Nicolas Pitre --- arch/arm/common/bL_switcher.c | 20 ++++++++++++++++++++ arch/arm/include/asm/bL_switcher.h | 2 ++ 2 files changed, 22 insertions(+) diff --git a/arch/arm/common/bL_switcher.c b/arch/arm/common/bL_switcher.c index f4878a3604..63bbc4f705 100644 --- a/arch/arm/common/bL_switcher.c +++ b/arch/arm/common/bL_switcher.c @@ -532,6 +532,26 @@ static int bL_switcher_halve_cpus(void) return 0; } +/* Determine the logical CPU a given physical CPU is grouped on. */ +int bL_switcher_get_logical_index(u32 mpidr) +{ + int cpu; + + if (!bL_switcher_active) + return -EUNATCH; + + mpidr &= MPIDR_HWID_BITMASK; + for_each_online_cpu(cpu) { + int pairing = bL_switcher_cpu_pairing[cpu]; + if (pairing == -1) + continue; + if ((mpidr == cpu_logical_map(cpu)) || + (mpidr == cpu_logical_map(pairing))) + return cpu; + } + return -EINVAL; +} + static void bL_switcher_trace_trigger_cpu(void *__always_unused info) { trace_cpu_migrate_current(get_ns(), read_mpidr()); diff --git a/arch/arm/include/asm/bL_switcher.h b/arch/arm/include/asm/bL_switcher.h index 8ada5a885c..1714800fa1 100644 --- a/arch/arm/include/asm/bL_switcher.h +++ b/arch/arm/include/asm/bL_switcher.h @@ -55,6 +55,7 @@ bool bL_switcher_get_enabled(void); void bL_switcher_put_enabled(void); int bL_switcher_trace_trigger(void); +int bL_switcher_get_logical_index(u32 mpidr); #else static inline int bL_switcher_register_notifier(struct notifier_block *nb) @@ -70,6 +71,7 @@ static inline int bL_switcher_unregister_notifier(struct notifier_block *nb) static inline bool bL_switcher_get_enabled(void) { return false; } static inline void bL_switcher_put_enabled(void) { } static inline int bL_switcher_trace_trigger(void) { return 0; } +static inline int bL_switcher_get_logical_index(u32 mpidr) { return -EUNATCH; } #endif /* CONFIG_BL_SWITCHER */ #endif