From patchwork Mon Jun 5 11:23:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Piggin X-Patchwork-Id: 13267237 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6BF5FC7EE24 for ; Mon, 5 Jun 2023 11:25:16 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q68Jo-0007Fu-DT; Mon, 05 Jun 2023 07:24:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q68JZ-0007Bx-Bk; Mon, 05 Jun 2023 07:24:01 -0400 Received: from mail-pj1-x102a.google.com ([2607:f8b0:4864:20::102a]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1q68JX-00067E-LH; Mon, 05 Jun 2023 07:23:57 -0400 Received: by mail-pj1-x102a.google.com with SMTP id 98e67ed59e1d1-256a41d3e81so3977076a91.1; Mon, 05 Jun 2023 04:23:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1685964233; x=1688556233; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=qtQv9mG/1sSAMYOSZ1PMqhqIDwmuO1AjyfDFNNYJ4CQ=; b=Kx+GQreeVYohMqWL/PKT0UTwcFEp7D0vZ3bEEfXc+2D2CvduLruFsR5BbKflnPlNE8 ljB2A46k5v5IxwytQICtM5VArbPGYiVz65NOP949hPnwGQc+QxW3uYMRwS+2y7ecbb87 k9DHdIQ9tyfQ77OrXqR6qS0QJcSwPrGUjAQDgeagFDe2i4Gb0aFX8xf5B0dHb+nEiy8P /nd9u8IMsOEymWXNgasa2wcigjB2P6D7usuh2Aj9exSlFyP2FviI6XKoDMvOFgxk4JBT SRaWuoz4d40vg7ZPO+RIlUZq6OHTOPpsR1sWDfg2taZRNDok1W6agyvXHKmTpO/2P4Xo aIAQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685964233; x=1688556233; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=qtQv9mG/1sSAMYOSZ1PMqhqIDwmuO1AjyfDFNNYJ4CQ=; b=MCBxiuRs2DYXke8Fq1Mjc8qt9tF1xdGgXwnRIiH5nxG5bxXqLMXdHdVPdp7gQwKqJ8 ymScHcpjKOOhQDO2SB7BW0iEQrv5IF8zpbz33dZI3sZiori2EqAdD+Bu5cI/xVoQLU0W w6RSF+Cz8eeAu7O2E1dCgb5K2W1JoagZdqxVv9M7RIKyw4gXF3feI0FBSz0WZj1+rB5+ oo88U1XBRvuXR2k/LOhYV4mJM6oHtQhH9CVQxBHN19sZ9/uh2EdJ93nL4VGgmYfYuAh2 dXUPW+VY/Os1Bh3CJSFIaFnTHNorMPUwUu9SyLclNIS7cDCO2rg14WbBuqlrdRokhYjm GUMw== X-Gm-Message-State: AC+VfDwQsEBcxomtSZIzeSYJwjHpG0VNsovNhA3RzQidZDEogZ8uFlzi tDgLqzQ/M5FAO5NQNNFDWgf06ynIoPE= X-Google-Smtp-Source: ACHHUZ7IFMan70FtO9cY4nejhhHnZYpL62tfZFVFboYlVhLmkQdbS7T8oRIu4S0NkxqH++rPuvMfiA== X-Received: by 2002:a17:90a:19d6:b0:259:548b:d385 with SMTP id 22-20020a17090a19d600b00259548bd385mr2172108pjj.3.1685964233362; Mon, 05 Jun 2023 04:23:53 -0700 (PDT) Received: from wheely.local0.net ([203.221.142.9]) by smtp.gmail.com with ESMTPSA id f32-20020a17090a702300b0024e026444b6sm15953385pjk.2.2023.06.05.04.23.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Jun 2023 04:23:52 -0700 (PDT) From: Nicholas Piggin To: qemu-ppc@nongnu.org Cc: Nicholas Piggin , qemu-devel@nongnu.org, Daniel Henrique Barboza , =?utf-8?q?C=C3=A9dric_?= =?utf-8?q?Le_Goater?= Subject: [PATCH 4/4] spapr: Allow up to 8 threads SMT on POWER8 and newer Date: Mon, 5 Jun 2023 21:23:23 +1000 Message-Id: <20230605112323.179259-5-npiggin@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230605112323.179259-1-npiggin@gmail.com> References: <20230605112323.179259-1-npiggin@gmail.com> MIME-Version: 1.0 Received-SPF: pass client-ip=2607:f8b0:4864:20::102a; envelope-from=npiggin@gmail.com; helo=mail-pj1-x102a.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org PPC TCG now supports multi-threaded CPU configuration for non-hypervisor state. This requires PIR and TIR be set, because that's how sibling thread matching is done. spapr's nested-HV capability does not currently coexist with SMT. This is quite analogous to LPAR-per-core mode on real hardware which also does not support KVM. Signed-off-by: Nicholas Piggin --- hw/ppc/spapr.c | 16 ++++++++++++---- hw/ppc/spapr_caps.c | 14 ++++++++++++++ hw/ppc/spapr_cpu_core.c | 7 +++++-- 3 files changed, 31 insertions(+), 6 deletions(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index dcb7f1c70a..deb8b507e3 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -2524,10 +2524,18 @@ static void spapr_set_vsmt_mode(SpaprMachineState *spapr, Error **errp) int ret; unsigned int smp_threads = ms->smp.threads; - if (!kvm_enabled() && (smp_threads > 1)) { - error_setg(errp, "TCG cannot support more than 1 thread/core " - "on a pseries machine"); - return; + if (!kvm_enabled()) { + if (!ppc_type_check_compat(ms->cpu_type, CPU_POWERPC_LOGICAL_2_07, 0, + spapr->max_compat_pvr)) { + error_setg(errp, "TCG only supports SMT on POWER8 or newer CPUs"); + return; + } + + if (smp_threads > 8) { + error_setg(errp, "TCG cannot support more than 8 threads/core " + "on a pseries machine"); + return; + } } if (!is_power_of_2(smp_threads)) { error_setg(errp, "Cannot support %d threads/core on a pseries " diff --git a/hw/ppc/spapr_caps.c b/hw/ppc/spapr_caps.c index 3fd45a6dec..03f02b4af3 100644 --- a/hw/ppc/spapr_caps.c +++ b/hw/ppc/spapr_caps.c @@ -473,6 +473,20 @@ static void cap_nested_kvm_hv_apply(SpaprMachineState *spapr, error_append_hint(errp, "Try appending -machine cap-nested-hv=off\n"); } + } else { + MachineState *ms = MACHINE(spapr); + unsigned int smp_threads = ms->smp.threads; + + /* + * Nested-HV vCPU env state to L2, so SMT-shared SPR updates, for + * example, do not necessarily update the correct SPR value on sibling + * threads that are in a different guest/host context. + */ + if (smp_threads > 1) { + error_setg(errp, "TCG does not support nested-HV with SMT"); + error_append_hint(errp, "Try appending -machine cap-nested-hv=off " + "or use threads=1 with -smp\n"); + } } } diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c index 9b88dd549a..a4e3c2fadd 100644 --- a/hw/ppc/spapr_cpu_core.c +++ b/hw/ppc/spapr_cpu_core.c @@ -255,7 +255,7 @@ static void spapr_cpu_core_unrealize(DeviceState *dev) } static bool spapr_realize_vcpu(PowerPCCPU *cpu, SpaprMachineState *spapr, - SpaprCpuCore *sc, Error **errp) + SpaprCpuCore *sc, int thread_index, Error **errp) { CPUPPCState *env = &cpu->env; CPUState *cs = CPU(cpu); @@ -267,6 +267,9 @@ static bool spapr_realize_vcpu(PowerPCCPU *cpu, SpaprMachineState *spapr, cpu_ppc_set_vhyp(cpu, PPC_VIRTUAL_HYPERVISOR(spapr)); kvmppc_set_papr(cpu); + env->spr_cb[SPR_PIR].default_value = cs->cpu_index; + env->spr_cb[SPR_TIR].default_value = thread_index; + /* Set time-base frequency to 512 MHz. vhyp must be set first. */ cpu_ppc_tb_init(env, SPAPR_TIMEBASE_FREQ); @@ -337,7 +340,7 @@ static void spapr_cpu_core_realize(DeviceState *dev, Error **errp) for (i = 0; i < cc->nr_threads; i++) { sc->threads[i] = spapr_create_vcpu(sc, i, errp); if (!sc->threads[i] || - !spapr_realize_vcpu(sc->threads[i], spapr, sc, errp)) { + !spapr_realize_vcpu(sc->threads[i], spapr, sc, i, errp)) { spapr_cpu_core_unrealize(dev); return; }