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=-10.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,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 966E0C433ED for ; Tue, 13 Apr 2021 20:33:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6C9D661027 for ; Tue, 13 Apr 2021 20:33:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348220AbhDMUeR (ORCPT ); Tue, 13 Apr 2021 16:34:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54086 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229589AbhDMUeQ (ORCPT ); Tue, 13 Apr 2021 16:34:16 -0400 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 79525C061574 for ; Tue, 13 Apr 2021 13:33:56 -0700 (PDT) Received: by mail-pg1-x52b.google.com with SMTP id k8so12785547pgf.4 for ; Tue, 13 Apr 2021 13:33:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=oSdlg5xvaQDZsLoPWHTKgWWHFxjvxtKQ5zr5fbA5PpQ=; b=WylbRjVSQ+LLbMeRn6+8/7fHGfn8keiW5mt5TLp74Lby8sHnNOp0MjPpHXGN7AfTtl 6THUNZtVGZCEU5ppa+c1RGGvtzZUur/eTiVWBisZhz6j6c4f9CTNgrPVvCai3+AsyEPw 5DTsCcyr1TAXNAUq07v8T0ZgkwKAwDWRwvxfHj1RGsJ4gHmTXFoW6JVGIS1eWaD6w7gF DSwJdWhpvy5b/dD93dYlczAqhOYMW38OVt2tx2zJ6R6zVWXW0UbDxgZTMfXLCR8ZEJPg Z371oM9MSyesNF/faReHGF+nln/VabFNEdH6AWxk4/Kfdl8h493XPBPl4b8WRowdknT/ Erew== 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:mime-version :content-transfer-encoding; bh=oSdlg5xvaQDZsLoPWHTKgWWHFxjvxtKQ5zr5fbA5PpQ=; b=sHSzOBtvUYpSN1hsl4jsKvbiQJD4SlwoIRA1VFst2dnaCfnF28mSR+8WaVmqBHoGkF 9mO43XtkNHL33G27+YpjCNtD+wuIkrdxv55LFucDex5hvLO2ykPxcLs1Mdm6wzWOQqhK n4vijPAbmVdHL6WUZdDvjyS+1W5Mg2HsyFDQHPgiiuCrxLJnOyF3R0c1HL6d6WJKZOvJ 3BJAh1VpQMKSkwMKX7T9EWL2dp/AGvwB3k6CnZGiTaBy+cr88ef2uS0G0iOf+6jv0wFQ L+10iKPvXwZq+1Vm0eHukKkqNImJclgXPuELSwMNN7HbHMRsk6q2annV0T/hbGdV5RM1 SIMg== X-Gm-Message-State: AOAM532mUDPbz3H4PfZl/MJw9BhY5FQ1POxJQfRDZVkPuCDY0j1C8OB8 MTBu0zDzhRwmHpKCz3Rm79+ZPJl7j5E= X-Google-Smtp-Source: ABdhPJyJxgaU0AtjIKqZmJM1Gsr15nczkOPK+ruhLr1Ccl0dm0d1eLXJ7XJy6jRN456ylKBvD0rlnA== X-Received: by 2002:aa7:9f45:0:b029:24e:6fe8:5bf0 with SMTP id h5-20020aa79f450000b029024e6fe85bf0mr9158416pfr.79.1618346036114; Tue, 13 Apr 2021 13:33:56 -0700 (PDT) Received: from edumazet1.svl.corp.google.com ([2620:15c:2c4:201:a476:17ee:13ea:2981]) by smtp.gmail.com with ESMTPSA id 20sm89970pfw.40.2021.04.13.13.33.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Apr 2021 13:33:55 -0700 (PDT) From: Eric Dumazet To: Ingo Molnar , Mathieu Desnoyers , Peter Zijlstra Cc: "Paul E . McKenney" , Boqun Feng , Arjun Roy , linux-kernel , Eric Dumazet , Eric Dumazet Subject: [PATCH v3 0/3] rseq: minor optimizations Date: Tue, 13 Apr 2021 13:33:49 -0700 Message-Id: <20210413203352.71350-1-eric.dumazet@gmail.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Dumazet rseq is a heavy user of copy to/from user data in fast paths. This series tries to reduce the cost. v3: Third patch going back to v1 (only deal with 64bit arches) v2: Addressed Peter and Mathieu feedbacks, thanks ! Eric Dumazet (3): rseq: optimize rseq_update_cpu_id() rseq: remove redundant access_ok() rseq: optimise rseq_get_rseq_cs() and clear_rseq_cs() kernel/rseq.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) -- 2.31.1.295.g9ea45b61b8-goog