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=-13.5 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 9B41DC433B4 for ; Mon, 5 Apr 2021 01:31:04 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1454A61158 for ; Mon, 5 Apr 2021 01:31:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1454A61158 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4FDCm65mzHz3fvN for ; Mon, 5 Apr 2021 11:31:02 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=d+yzFvdJ; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gmail.com (client-ip=2607:f8b0:4864:20::102c; helo=mail-pj1-x102c.google.com; envelope-from=npiggin@gmail.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=d+yzFvdJ; dkim-atps=neutral Received: from mail-pj1-x102c.google.com (mail-pj1-x102c.google.com [IPv6:2607:f8b0:4864:20::102c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4FDCY36NZDz3c9D for ; Mon, 5 Apr 2021 11:21:27 +1000 (AEST) Received: by mail-pj1-x102c.google.com with SMTP id ha17so5269372pjb.2 for ; Sun, 04 Apr 2021 18:21:27 -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:in-reply-to:references :mime-version:content-transfer-encoding; bh=eg/LONsL/v52XjsVvWJ/gHvuI8LKJE3Kwm8pO3cmUh0=; b=d+yzFvdJsE6Udw/oxnGd3ktn5ac7k831rkFpUl8FtxS001A2LxpL5O7ag2EL8uzCX3 oNP9V76IiCg8Yt/mREBeiXENpwdVugAk1mYOOibYGRzjwfY4z35OqXiOQtQqTlzO6FKE SyjYiAygNkZNZNDg8mNnXq6bVYFkWPvmDrRnrp0pyRHGaDY+X2np7tMi+8n2E9Ybjujs hIOCTF6iS1bPz3WidEreQ2IbdV5terOn84aWpepT/gHuJF+7tHTPjDSA6XM2crwJwiAb KM5wrSLH/b4XtULkAs2qwB1XjUZO87BJ1zfrGzvLV24U11X42SLmEYC7Efj3q0cGu9rg CoCw== 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=eg/LONsL/v52XjsVvWJ/gHvuI8LKJE3Kwm8pO3cmUh0=; b=kTDHfdSgWKNfhCTVMmDa8m8GDKArDpldzvZSfk1xJFsMe5Of4MXZrd5Z700B9V4If2 nvtsyMzqYKQ8igdg/n/5t+wHVP9jiPzSNlc288oJoEo854+l7zFdzLbxZkc4ZgsAVXUp wep8hj5l5Ah7uiUnOJw7mNAE1A0AGW97qvzooiOUNQlqZp5pNErluNYLMbOqcLaDfrH8 hvv7JNs1wzsmWYJBGEPB3F/FV+iSNdC1FoH5emWJXB21BJ/vcXoFYpb5i57YYYXOSAu1 8ZMKzLNwvo94tB9PgbFnu+bqMwdiIWFMENBkLNVsSkJaN2q09GBVdNaFxk4FYpWVzm7X PqSg== X-Gm-Message-State: AOAM533HSoxizeKZdkqByDJ/rGFqSZ7uD6Q3FkO9SfkRyML7keFvIAc7 xFsZaOxdhq9MBm6v0fSNzq4= X-Google-Smtp-Source: ABdhPJwuC5NMjyPrlIoyrCpfwlN5Tc7wQeInmrVcBhfZFtuqGaK5f1sraFyGvnd4fEdyS7KGbpZQpw== X-Received: by 2002:a17:902:780c:b029:e6:9193:56e2 with SMTP id p12-20020a170902780cb02900e6919356e2mr21811789pll.39.1617585686267; Sun, 04 Apr 2021 18:21:26 -0700 (PDT) Received: from bobo.ibm.com ([1.132.215.134]) by smtp.gmail.com with ESMTPSA id e3sm14062536pfm.43.2021.04.04.18.21.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 04 Apr 2021 18:21:26 -0700 (PDT) From: Nicholas Piggin To: kvm-ppc@vger.kernel.org Subject: [PATCH v6 24/48] KVM: PPC: Book3S HV P9: Use large decrementer for HDEC Date: Mon, 5 Apr 2021 11:19:24 +1000 Message-Id: <20210405011948.675354-25-npiggin@gmail.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20210405011948.675354-1-npiggin@gmail.com> References: <20210405011948.675354-1-npiggin@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alexey Kardashevskiy , linuxppc-dev@lists.ozlabs.org, Nicholas Piggin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On processors that don't suppress the HDEC exceptions when LPCR[HDICE]=0, this could help reduce needless guest exits due to leftover exceptions on entering the guest. Reviewed-by: Alexey Kardashevskiy Signed-off-by: Nicholas Piggin --- arch/powerpc/include/asm/time.h | 2 ++ arch/powerpc/kernel/time.c | 1 + arch/powerpc/kvm/book3s_hv.c | 3 ++- 3 files changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/time.h b/arch/powerpc/include/asm/time.h index 8dd3cdb25338..68d94711811e 100644 --- a/arch/powerpc/include/asm/time.h +++ b/arch/powerpc/include/asm/time.h @@ -18,6 +18,8 @@ #include /* time.c */ +extern u64 decrementer_max; + extern unsigned long tb_ticks_per_jiffy; extern unsigned long tb_ticks_per_usec; extern unsigned long tb_ticks_per_sec; diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index b67d93a609a2..fc42594c8223 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -89,6 +89,7 @@ static struct clocksource clocksource_timebase = { #define DECREMENTER_DEFAULT_MAX 0x7FFFFFFF u64 decrementer_max = DECREMENTER_DEFAULT_MAX; +EXPORT_SYMBOL_GPL(decrementer_max); /* for KVM HDEC */ static int decrementer_set_next_event(unsigned long evt, struct clock_event_device *dev); diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index f2aefd478d8c..3029ffb4b792 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -3675,7 +3675,8 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit, vc->tb_offset_applied = 0; } - mtspr(SPRN_HDEC, 0x7fffffff); + /* HDEC must be at least as large as DEC, so decrementer_max fits */ + mtspr(SPRN_HDEC, decrementer_max); switch_mmu_to_host_radix(kvm, host_pidr); -- 2.23.0 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicholas Piggin Date: Mon, 05 Apr 2021 01:19:24 +0000 Subject: [PATCH v6 24/48] KVM: PPC: Book3S HV P9: Use large decrementer for HDEC Message-Id: <20210405011948.675354-25-npiggin@gmail.com> List-Id: References: <20210405011948.675354-1-npiggin@gmail.com> In-Reply-To: <20210405011948.675354-1-npiggin@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kvm-ppc@vger.kernel.org Cc: Alexey Kardashevskiy , linuxppc-dev@lists.ozlabs.org, Nicholas Piggin On processors that don't suppress the HDEC exceptions when LPCR[HDICE]=0, this could help reduce needless guest exits due to leftover exceptions on entering the guest. Reviewed-by: Alexey Kardashevskiy Signed-off-by: Nicholas Piggin --- arch/powerpc/include/asm/time.h | 2 ++ arch/powerpc/kernel/time.c | 1 + arch/powerpc/kvm/book3s_hv.c | 3 ++- 3 files changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/time.h b/arch/powerpc/include/asm/time.h index 8dd3cdb25338..68d94711811e 100644 --- a/arch/powerpc/include/asm/time.h +++ b/arch/powerpc/include/asm/time.h @@ -18,6 +18,8 @@ #include /* time.c */ +extern u64 decrementer_max; + extern unsigned long tb_ticks_per_jiffy; extern unsigned long tb_ticks_per_usec; extern unsigned long tb_ticks_per_sec; diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index b67d93a609a2..fc42594c8223 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -89,6 +89,7 @@ static struct clocksource clocksource_timebase = { #define DECREMENTER_DEFAULT_MAX 0x7FFFFFFF u64 decrementer_max = DECREMENTER_DEFAULT_MAX; +EXPORT_SYMBOL_GPL(decrementer_max); /* for KVM HDEC */ static int decrementer_set_next_event(unsigned long evt, struct clock_event_device *dev); diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index f2aefd478d8c..3029ffb4b792 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -3675,7 +3675,8 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit, vc->tb_offset_applied = 0; } - mtspr(SPRN_HDEC, 0x7fffffff); + /* HDEC must be at least as large as DEC, so decrementer_max fits */ + mtspr(SPRN_HDEC, decrementer_max); switch_mmu_to_host_radix(kvm, host_pidr); -- 2.23.0