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=-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=ham 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 1B581C432BE for ; Sun, 29 Aug 2021 10:23:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDA1E60E90 for ; Sun, 29 Aug 2021 10:23:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235128AbhH2KXz (ORCPT ); Sun, 29 Aug 2021 06:23:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37746 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235122AbhH2KXz (ORCPT ); Sun, 29 Aug 2021 06:23:55 -0400 Received: from mail-pf1-x42c.google.com (mail-pf1-x42c.google.com [IPv6:2607:f8b0:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 909BEC061756 for ; Sun, 29 Aug 2021 03:23:03 -0700 (PDT) Received: by mail-pf1-x42c.google.com with SMTP id x19so2772785pfu.4 for ; Sun, 29 Aug 2021 03:23:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=+tIlR3yAnihc/8N68dAkVCR/HC1yo91sWJBQN/lr8bM=; b=EpBQc1jEbWZQDKA/Hd96/dSblduNlrZBfncFOQFXZpBZasUh1zyFsHwfMwKgYRKn2h q4NE7GP+NXGct8xScaCRIZnWy+hcmxCEq/nCYqgCQNL6rwF/YRU1M6f1fD4O4cbNoTzz uXwFsacODV17YlAKMBclA++GTdimgD4pqTRn5Q4GCyKHe6AgjXLUHb8GqfqPlIGscUaX ZgDzHZA0qamkZz1/SgpKYCbiJR76MPDn6r/4PVd/QIasX3mNJggJd6mDMt0CtC5TAb4i KmmVTatyoe7/Mi9gAG1PbwKdoNzQK3A0UihvZVjffBNZQkyZ5IEgzccZ6tRbr9QFbn7X 5f6g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=+tIlR3yAnihc/8N68dAkVCR/HC1yo91sWJBQN/lr8bM=; b=PKVsaS/u7hb+RHEz08mWhV/O6Ms7QQvc9Rl1qEo2DxWSIlrcfUjMWyXuEZwJBOFoH3 uT7a8GqpUF0ax8OemJeSxc7ostbzEJtEt+AcnXLL58dmUud37Fmyj95KduuTIeqF9lpD cIek7hDTl2SMGxuq6uZTH84yncVvBfg8dHKir5m0xgv7oBsUOploXYiQNSYCMPuUAQNK HH8GVDHz2ot5wGODIzt3zCs225KxyI6Sja5gG6DZHSJ51Kxnh1Vz/sEz1zFFTV5BADGC KrFCZQZ8tHYzrV8+jL5AaZf2BILU82GI68+5btHnUKvDAqlVSAt89biB41Lo0ke7ehe0 r4Ew== X-Gm-Message-State: AOAM530/kWCsz0/WJdXvPG7I0UJu8maUbV0CLpgWU/d9vUJG4IjXr9WE 7Y8zK93M8kq2AFsmebFUldkV0w== X-Google-Smtp-Source: ABdhPJx0z9GdJsy4ggFkGrduZsKKGG/vfDnVoFB9KZKLY9yy2wtvbqbnc5phggOaYFxXoxCi8NiAQQ== X-Received: by 2002:a62:8603:0:b029:3c8:3fdb:4aea with SMTP id x3-20020a6286030000b02903c83fdb4aeamr17882261pfd.6.1630232583070; Sun, 29 Aug 2021 03:23:03 -0700 (PDT) Received: from localhost ([134.195.101.46]) by smtp.gmail.com with ESMTPSA id b20sm11404522pfl.9.2021.08.29.03.23.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 29 Aug 2021 03:23:02 -0700 (PDT) From: Leo Yan To: Arnaldo Carvalho de Melo , Adrian Hunter , James Clark , Mathieu Poirier , Suzuki K Poulose , Mike Leach , John Garry , Will Deacon , Peter Zijlstra , Ingo Molnar , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Andi Kleen , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, "Russell King (Oracle)" Cc: Leo Yan Subject: [PATCH v2 2/2] perf auxtrace arm: Support compat_auxtrace_mmap__{read_head|write_tail} Date: Sun, 29 Aug 2021 18:22:38 +0800 Message-Id: <20210829102238.19693-3-leo.yan@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210829102238.19693-1-leo.yan@linaro.org> References: <20210829102238.19693-1-leo.yan@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org When the tool runs with compat mode on Arm platform, the kernel is in 64-bit mode and user space is in 32-bit mode; the user space can use instructions "ldrd" and "strd" for 64-bit value atomicity. This patch adds compat_auxtrace_mmap__{read_head|write_tail} for arm building, it uses "ldrd" and "strd" instructions to ensure accessing atomicity for aux head and tail. The file arch/arm/util/auxtrace.c is built for arm and arm64 building, these two functions are not needed for arm64, so check the compiler macro "__arm__" to only include them for arm building. Signed-off-by: Leo Yan Reviewed-by: James Clark Tested-by: James Clark --- tools/perf/arch/arm/util/auxtrace.c | 32 +++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/tools/perf/arch/arm/util/auxtrace.c b/tools/perf/arch/arm/util/auxtrace.c index b187bddbd01a..c7c7ec0812d5 100644 --- a/tools/perf/arch/arm/util/auxtrace.c +++ b/tools/perf/arch/arm/util/auxtrace.c @@ -107,3 +107,35 @@ struct auxtrace_record *err = 0; return NULL; } + +#if defined(__arm__) +u64 compat_auxtrace_mmap__read_head(struct auxtrace_mmap *mm) +{ + struct perf_event_mmap_page *pc = mm->userpg; + u64 result; + + __asm__ __volatile__( +" ldrd %0, %H0, [%1]" + : "=&r" (result) + : "r" (&pc->aux_head), "Qo" (pc->aux_head) + ); + + return result; +} + +int compat_auxtrace_mmap__write_tail(struct auxtrace_mmap *mm, u64 tail) +{ + struct perf_event_mmap_page *pc = mm->userpg; + + /* Ensure all reads are done before we write the tail out */ + smp_mb(); + + __asm__ __volatile__( +" strd %2, %H2, [%1]" + : "=Qo" (pc->aux_tail) + : "r" (&pc->aux_tail), "r" (tail) + ); + + return 0; +} +#endif -- 2.25.1