From patchwork Wed Aug 11 16:00:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Piggin X-Patchwork-Id: 1515899 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=kvm-ppc-owner@vger.kernel.org; receiver=) Authentication-Results: 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=tEdIQaqs; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4GlF301PJXz9t1s for ; Thu, 12 Aug 2021 02:02:52 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233628AbhHKQDP (ORCPT ); Wed, 11 Aug 2021 12:03:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229634AbhHKQDP (ORCPT ); Wed, 11 Aug 2021 12:03:15 -0400 Received: from mail-pj1-x1029.google.com (mail-pj1-x1029.google.com [IPv6:2607:f8b0:4864:20::1029]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5A72EC061765 for ; Wed, 11 Aug 2021 09:02:51 -0700 (PDT) Received: by mail-pj1-x1029.google.com with SMTP id 28-20020a17090a031cb0290178dcd8a4d1so5350257pje.0 for ; Wed, 11 Aug 2021 09:02:51 -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=Q0d0iaopUkL57P/YF2EiZzRzVhFFGYIegIp/ZQI3dO8=; b=tEdIQaqs2HRZCjge8fh1ibXHwlZC+5KChx8ndqotUyE69jWlERwDq7ecjhtfEBxaBq K9O8G/N6GpS9Yc6P16JFFjYuO0HTfWNOe1PWBe3+7Wt1nfPFR+K5M80NCIAqLtz979kP /i2b+qbrFPNc0NgluKbYwJG5PHIAVKQxwOMgPepDqWo/STuhyDM0vLLizY6OeqTClPMU ugyDxaqDn6bYXm6dmnwEeGyNRKePgbpwtSSQ0Tyb07jyo0k7OWn/BDhKBjSks58uB/8n G6ToDuGVYYcnT2gswCIC9QbM/wYQYvg6b3ReZxeJ2xkpjY4E3zLaoqH8tt5iAdXL4liF GlOw== 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=Q0d0iaopUkL57P/YF2EiZzRzVhFFGYIegIp/ZQI3dO8=; b=cOaXIGNpakDHbiDkeqEJjC/71ry/XLZCUBtWzgQX33KDhEZwSV7EHpBox26g4lbSjH tXwEHgrwAtRZvsdghxP5SjrdbQVKXwne5W9PSyiccn3UuvQ0aaCDF73A+OsnITdx5GCh a6szu6m1oNIV3buJkCHeMHIzPam/B+u9N/myGIBxFe6i27mApQ+x8svU2IYXSGux26kB 7/fN6qIa0Meor8dBgqWpI3D2Z7zBQPjpDMXmdc3ENMj37HCnBwCjn481Lfv4SFKRXD6r lXmiLOj9pPg50F4LbXP46Yo8d2qD6LbmjAYkYHipx29spMAf7CeytAOJk1QN0IEJXftX wqBg== X-Gm-Message-State: AOAM530yLAXNjVEnk5qaK0S4HQspURPuP3jn0PXMYs7TzBTdnyhJhPMO WQ7yKTz5KbHmMD/OkXCwiTaQ0fbu5KY= X-Google-Smtp-Source: ABdhPJzd+cZm7lc8lSMZdvmG9Mg0irEwwXBZrOzKs7aJnrs7cThmGx00AGnzug/cEOiJRet08RQRpQ== X-Received: by 2002:a17:90a:a091:: with SMTP id r17mr4239723pjp.56.1628697770805; Wed, 11 Aug 2021 09:02:50 -0700 (PDT) Received: from bobo.ibm.com ([118.210.97.79]) by smtp.gmail.com with ESMTPSA id k19sm6596494pff.28.2021.08.11.09.02.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Aug 2021 09:02:50 -0700 (PDT) From: Nicholas Piggin To: kvm-ppc@vger.kernel.org Cc: Nicholas Piggin , linuxppc-dev@lists.ozlabs.org Subject: [PATCH v2 25/60] KVM: PPC: Book3S HV: CTRL SPR does not require read-modify-write Date: Thu, 12 Aug 2021 02:00:59 +1000 Message-Id: <20210811160134.904987-26-npiggin@gmail.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20210811160134.904987-1-npiggin@gmail.com> References: <20210811160134.904987-1-npiggin@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm-ppc@vger.kernel.org Processors that support KVM HV do not require read-modify-write of the CTRL SPR to set/clear their thread's runlatch. Just write 1 or 0 to it. Signed-off-by: Nicholas Piggin --- arch/powerpc/kvm/book3s_hv.c | 2 +- arch/powerpc/kvm/book3s_hv_rmhandlers.S | 15 ++++++--------- 2 files changed, 7 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index fa12a3efeeb2..f9942eeaefd3 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -4060,7 +4060,7 @@ static void load_spr_state(struct kvm_vcpu *vcpu) */ if (!(vcpu->arch.ctrl & 1)) - mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1); + mtspr(SPRN_CTRLT, 0); } static void store_spr_state(struct kvm_vcpu *vcpu) diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 551ce223b40c..05be8648937d 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -775,12 +775,11 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S) mtspr SPRN_AMR,r5 mtspr SPRN_UAMOR,r6 - /* Restore state of CTRL run bit; assume 1 on entry */ + /* Restore state of CTRL run bit; the host currently has it set to 1 */ lwz r5,VCPU_CTRL(r4) andi. r5,r5,1 bne 4f - mfspr r6,SPRN_CTRLF - clrrdi r6,r6,1 + li r6,0 mtspr SPRN_CTRLT,r6 4: /* Secondary threads wait for primary to have done partition switch */ @@ -1203,12 +1202,12 @@ guest_bypass: stw r0, VCPU_CPU(r9) stw r0, VCPU_THREAD_CPU(r9) - /* Save guest CTRL register, set runlatch to 1 */ + /* Save guest CTRL register, set runlatch to 1 if it was clear */ mfspr r6,SPRN_CTRLF stw r6,VCPU_CTRL(r9) andi. r0,r6,1 bne 4f - ori r6,r6,1 + li r6,1 mtspr SPRN_CTRLT,r6 4: /* @@ -2178,8 +2177,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_TM) * Also clear the runlatch bit before napping. */ kvm_do_nap: - mfspr r0, SPRN_CTRLF - clrrdi r0, r0, 1 + li r0,0 mtspr SPRN_CTRLT, r0 li r0,1 @@ -2198,8 +2196,7 @@ kvm_nap_sequence: /* desired LPCR value in r5 */ bl isa206_idle_insn_mayloss - mfspr r0, SPRN_CTRLF - ori r0, r0, 1 + li r0,1 mtspr SPRN_CTRLT, r0 mtspr SPRN_SRR1, r3