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[2001:4830:134:3::11]) by mx.google.com with ESMTPS id b29si3303219qta.263.2017.01.27.03.19.47 for (version=TLS1 cipher=AES128-SHA bits=128/128); Fri, 27 Jan 2017 03:19:48 -0800 (PST) Received-SPF: pass (google.com: domain of qemu-devel-bounces+patch=linaro.org@nongnu.org designates 2001:4830:134:3::11 as permitted sender) client-ip=2001:4830:134:3::11; Authentication-Results: mx.google.com; dkim=fail header.i=@linaro.org; spf=pass (google.com: domain of qemu-devel-bounces+patch=linaro.org@nongnu.org designates 2001:4830:134:3::11 as permitted sender) smtp.mailfrom=qemu-devel-bounces+patch=linaro.org@nongnu.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: from localhost ([::1]:44455 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cX4ZF-0007cF-S8 for patch@linaro.org; Fri, 27 Jan 2017 06:19:45 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48993) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cX3wT-0003U6-Ra for qemu-devel@nongnu.org; Fri, 27 Jan 2017 05:39:43 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cX3wS-0003ai-F3 for qemu-devel@nongnu.org; Fri, 27 Jan 2017 05:39:41 -0500 Received: from mail-wm0-x22e.google.com ([2a00:1450:400c:c09::22e]:37685) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cX3wR-0003a8-RQ for qemu-devel@nongnu.org; Fri, 27 Jan 2017 05:39:40 -0500 Received: by mail-wm0-x22e.google.com with SMTP id c206so130184696wme.0 for ; Fri, 27 Jan 2017 02:39:39 -0800 (PST) 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=wteZ9HPk/LB0YnUKNcFFZ3fdS6sGUP564feMjuMOMqs=; b=j6xaB9uRg+sX3WQwtRrHDBRHf3ZYvZg934Ripmy7rnFLGML8Br415LghXLuJ8qm6DZ UCdmhXMdDatDUyG2SxHbD3Xb8SFBgxSw3Uqcfvh9ReNwA7JrNXf3sutBpVMH+xiv9vkO L8sGWo3y6zvfIWBz0e8sHe8BkKvTlflkBFcOs= 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=wteZ9HPk/LB0YnUKNcFFZ3fdS6sGUP564feMjuMOMqs=; b=etPzbcsUN0ov0mCWbi4B4px/YYp+s1I/NTOIWaJeHp6SdDFRXcFvJw0zHNGvzcUQYC 89bpWb6NX5aV7POcV3Fs3yvaeREP+Y+sa9eK/otDZ6PrLJHrmI/s+nSYJ42QWEGSBh95 pjl2BUMVskUmJ0WveNGxvjoWn/2pkiYAuPqk9wZZmKq4PdRFG06n2fLwghsjCR/loWu5 WXcPo/DWARzmy1gSjwvQocs5eQXW9qcE5oew7RslQWReG93mCzU8B2ZEbAYucr0fZKEt Da2MhxhcpZ3xhbMZ+M18V9Ufb0u9mdpfsV1LVgcnQZHuZCxsN3UdS+2nYiF6L6oeWA/G iuxA== X-Gm-Message-State: AIkVDXJnvpqTr/307n1/qXGaNHZRgDmrYCpUd3LyY2Ckw5R2lZ5k9nm9P6/fxuaSY4Zal16R X-Received: by 10.28.128.131 with SMTP id b125mr2655510wmd.7.1485513578711; Fri, 27 Jan 2017 02:39:38 -0800 (PST) Received: from zen.linaro.local ([81.128.185.34]) by smtp.gmail.com with ESMTPSA id w70sm7131681wrc.47.2017.01.27.02.39.30 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 27 Jan 2017 02:39:35 -0800 (PST) Received: from zen.linaroharston (localhost [127.0.0.1]) by zen.linaro.local (Postfix) with ESMTP id 0E0473E3777; Fri, 27 Jan 2017 10:39:24 +0000 (GMT) From: =?utf-8?q?Alex_Benn=C3=A9e?= To: mttcg@listserver.greensocs.com, qemu-devel@nongnu.org, fred.konrad@greensocs.com, a.rigo@virtualopensystems.com, cota@braap.org, bobby.prani@gmail.com, nikunj@linux.vnet.ibm.com Date: Fri, 27 Jan 2017 10:39:17 +0000 Message-Id: <20170127103922.19658-21-alex.bennee@linaro.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170127103922.19658-1-alex.bennee@linaro.org> References: <20170127103922.19658-1-alex.bennee@linaro.org> MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2a00:1450:400c:c09::22e Subject: [Qemu-devel] [PATCH v8 20/25] target-arm/powerctl: defer cpu reset work to CPU context X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peter.maydell@linaro.org, claudio.fontana@huawei.com, jan.kiszka@siemens.com, mark.burton@greensocs.com, "open list:ARM" , serge.fdrv@gmail.com, pbonzini@redhat.com, =?utf-8?q?Alex_Benn=C3=A9e?= , bamvor.zhangjian@linaro.org, rth@twiddle.net Errors-To: qemu-devel-bounces+patch=linaro.org@nongnu.org Sender: "Qemu-devel" When switching a new vCPU on we want to complete a bunch of the setup work before we start scheduling the vCPU thread. To do this cleanly we defer vCPU setup to async work which will run the vCPUs execution context as the thread is woken up. The scheduling of the work will kick the vCPU awake. This avoids potential races in MTTCG system emulation. Signed-off-by: Alex Bennée Reviewed-by: Richard Henderson --- v7 - add const to static mode_for_el[] array - fix checkpatch long lines --- target/arm/arm-powerctl.c | 146 ++++++++++++++++++++++++++++------------------ 1 file changed, 88 insertions(+), 58 deletions(-) -- 2.11.0 diff --git a/target/arm/arm-powerctl.c b/target/arm/arm-powerctl.c index fbb7a15daa..082788e3a4 100644 --- a/target/arm/arm-powerctl.c +++ b/target/arm/arm-powerctl.c @@ -48,11 +48,87 @@ CPUState *arm_get_cpu_by_id(uint64_t id) return NULL; } +struct cpu_on_info { + uint64_t entry; + uint64_t context_id; + uint32_t target_el; + bool target_aa64; +}; + + +static void arm_set_cpu_on_async_work(CPUState *target_cpu_state, + run_on_cpu_data data) +{ + ARMCPU *target_cpu = ARM_CPU(target_cpu_state); + struct cpu_on_info *info = (struct cpu_on_info *) data.host_ptr; + + /* Initialize the cpu we are turning on */ + cpu_reset(target_cpu_state); + target_cpu->powered_off = false; + target_cpu_state->halted = 0; + + if (info->target_aa64) { + if ((info->target_el < 3) && arm_feature(&target_cpu->env, + ARM_FEATURE_EL3)) { + /* + * As target mode is AArch64, we need to set lower + * exception level (the requested level 2) to AArch64 + */ + target_cpu->env.cp15.scr_el3 |= SCR_RW; + } + + if ((info->target_el < 2) && arm_feature(&target_cpu->env, + ARM_FEATURE_EL2)) { + /* + * As target mode is AArch64, we need to set lower + * exception level (the requested level 1) to AArch64 + */ + target_cpu->env.cp15.hcr_el2 |= HCR_RW; + } + + target_cpu->env.pstate = aarch64_pstate_mode(info->target_el, true); + } else { + /* We are requested to boot in AArch32 mode */ + static const uint32_t mode_for_el[] = { 0, + ARM_CPU_MODE_SVC, + ARM_CPU_MODE_HYP, + ARM_CPU_MODE_SVC }; + + cpsr_write(&target_cpu->env, mode_for_el[info->target_el], CPSR_M, + CPSRWriteRaw); + } + + if (info->target_el == 3) { + /* Processor is in secure mode */ + target_cpu->env.cp15.scr_el3 &= ~SCR_NS; + } else { + /* Processor is not in secure mode */ + target_cpu->env.cp15.scr_el3 |= SCR_NS; + } + + /* We check if the started CPU is now at the correct level */ + assert(info->target_el == arm_current_el(&target_cpu->env)); + + if (info->target_aa64) { + target_cpu->env.xregs[0] = info->context_id; + target_cpu->env.thumb = false; + } else { + target_cpu->env.regs[0] = info->context_id; + target_cpu->env.thumb = info->entry & 1; + info->entry &= 0xfffffffe; + } + + /* Start the new CPU at the requested address */ + cpu_set_pc(target_cpu_state, info->entry); + g_free(info); +} + int arm_set_cpu_on(uint64_t cpuid, uint64_t entry, uint64_t context_id, uint32_t target_el, bool target_aa64) { CPUState *target_cpu_state; ARMCPU *target_cpu; + struct cpu_on_info *info; DPRINTF("cpu %" PRId64 " (EL %d, %s) @ 0x%" PRIx64 " with R0 = 0x%" PRIx64 "\n", cpuid, target_el, target_aa64 ? "aarch64" : "aarch32", entry, @@ -109,64 +185,18 @@ int arm_set_cpu_on(uint64_t cpuid, uint64_t entry, uint64_t context_id, return QEMU_ARM_POWERCTL_INVALID_PARAM; } - /* Initialize the cpu we are turning on */ - cpu_reset(target_cpu_state); - target_cpu->powered_off = false; - target_cpu_state->halted = 0; - - if (target_aa64) { - if ((target_el < 3) && arm_feature(&target_cpu->env, ARM_FEATURE_EL3)) { - /* - * As target mode is AArch64, we need to set lower - * exception level (the requested level 2) to AArch64 - */ - target_cpu->env.cp15.scr_el3 |= SCR_RW; - } - - if ((target_el < 2) && arm_feature(&target_cpu->env, ARM_FEATURE_EL2)) { - /* - * As target mode is AArch64, we need to set lower - * exception level (the requested level 1) to AArch64 - */ - target_cpu->env.cp15.hcr_el2 |= HCR_RW; - } - - target_cpu->env.pstate = aarch64_pstate_mode(target_el, true); - } else { - /* We are requested to boot in AArch32 mode */ - static uint32_t mode_for_el[] = { 0, - ARM_CPU_MODE_SVC, - ARM_CPU_MODE_HYP, - ARM_CPU_MODE_SVC }; - - cpsr_write(&target_cpu->env, mode_for_el[target_el], CPSR_M, - CPSRWriteRaw); - } - - if (target_el == 3) { - /* Processor is in secure mode */ - target_cpu->env.cp15.scr_el3 &= ~SCR_NS; - } else { - /* Processor is not in secure mode */ - target_cpu->env.cp15.scr_el3 |= SCR_NS; - } - - /* We check if the started CPU is now at the correct level */ - assert(target_el == arm_current_el(&target_cpu->env)); - - if (target_aa64) { - target_cpu->env.xregs[0] = context_id; - target_cpu->env.thumb = false; - } else { - target_cpu->env.regs[0] = context_id; - target_cpu->env.thumb = entry & 1; - entry &= 0xfffffffe; - } - - /* Start the new CPU at the requested address */ - cpu_set_pc(target_cpu_state, entry); - - qemu_cpu_kick(target_cpu_state); + /* To avoid racing with a CPU we are just kicking off we do the + * final bit of preparation for the work in the target CPUs + * context. + */ + info = g_new(struct cpu_on_info, 1); + info->entry = entry; + info->context_id = context_id; + info->target_el = target_el; + info->target_aa64 = target_aa64; + + async_run_on_cpu(target_cpu_state, arm_set_cpu_on_async_work, + RUN_ON_CPU_HOST_PTR(info)); /* We are good to go */ return QEMU_ARM_POWERCTL_RET_SUCCESS;