From nobody Mon Apr 6 09:43:47 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9C34C54EE9 for ; Thu, 8 Sep 2022 23:27:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230372AbiIHX1X (ORCPT ); Thu, 8 Sep 2022 19:27:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44048 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230152AbiIHX0b (ORCPT ); Thu, 8 Sep 2022 19:26:31 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 61005108722; Thu, 8 Sep 2022 16:26:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1662679574; x=1694215574; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=N9V8aeLBeDyUCKjwvv3vkqyPtF2+WfmFX4Ug1U3Osmg=; b=HnIznXfiQs5okBhy8EWZxhIb+1oQmqqDS495TPsYv1dlKAyUzZ0Bcedx sa7tU2esSaypJIZ3K9ZY5pK8Iii+2AL3EykpNKX5GqZ1k20TWCBDUYU4I FleJYFAawzAL3QgoXmTmx868x/To5VRV86HNRpXXIEtuHx/JXEeAfkd3t yV5056RRP9m08lJ0dMEBMxAsKwJjlhGNh84O+w59Fh+220buT1p96cwX7 4qDW/6FdJeDXyz25TZAuYkn/s0SFiriygVAZNh8bDI/zWJLY5P0DlpaVx Fg/l3pQQtwGH2fwg4EFNYsPwcueHD4EXH0tQ54uY93p06FmNmAvXsdtiH A==; X-IronPort-AV: E=McAfee;i="6500,9779,10464"; a="298687017" X-IronPort-AV: E=Sophos;i="5.93,300,1654585200"; d="scan'208";a="298687017" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Sep 2022 16:26:11 -0700 X-IronPort-AV: E=Sophos;i="5.93,300,1654585200"; d="scan'208";a="610863245" Received: from ls.sc.intel.com (HELO localhost) ([143.183.96.54]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Sep 2022 16:26:11 -0700 From: isaku.yamahata@intel.com To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Paolo Bonzini , Sean Christopherson , Marc Zyngier , Will Deacon , Yuan Yao Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Kai Huang , Chao Gao , Atish Patra , Shaokun Zhang , Qi Liu , John Garry , Daniel Lezcano , Huang Ying , Huacai Chen Subject: [PATCH v4 16/26] KVM: kvm_arch.c: Remove a global variable, hardware_enable_failed Date: Thu, 8 Sep 2022 16:25:32 -0700 Message-Id: <60ca73d7d931ec8046ac50b20f05723a97ef643b.1662679124.git.isaku.yamahata@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Isaku Yamahata A global variable hardware_enable_failed in kvm_arch.c is used only by kvm_arch_add_vm() and hardware_enable(). It doesn't have to be a global variable. Make it function local. Signed-off-by: Isaku Yamahata --- virt/kvm/kvm_arch.c | 62 ++++++++++++++++++++++----------------------- 1 file changed, 31 insertions(+), 31 deletions(-) diff --git a/virt/kvm/kvm_arch.c b/virt/kvm/kvm_arch.c index 4fe16e8ef2e5..ad23537ebe3b 100644 --- a/virt/kvm/kvm_arch.c +++ b/virt/kvm/kvm_arch.c @@ -13,14 +13,13 @@ #include =20 static cpumask_t cpus_hardware_enabled =3D CPU_MASK_NONE; -static atomic_t hardware_enable_failed; =20 __weak int kvm_arch_post_init_vm(struct kvm *kvm) { return 0; } =20 -static void hardware_enable(void *caller_name) +static int __hardware_enable(void *caller_name) { int cpu =3D raw_smp_processor_id(); int r; @@ -28,18 +27,22 @@ static void hardware_enable(void *caller_name) WARN_ON_ONCE(preemptible()); =20 if (cpumask_test_cpu(cpu, &cpus_hardware_enabled)) - return; - - cpumask_set_cpu(cpu, &cpus_hardware_enabled); - + return 0; r =3D kvm_arch_hardware_enable(); - - if (r) { - cpumask_clear_cpu(cpu, &cpus_hardware_enabled); - atomic_inc(&hardware_enable_failed); + if (r) pr_warn("kvm: enabling virtualization on CPU%d failed during %s()\n", cpu, (const char *)caller_name); - } + else + cpumask_set_cpu(cpu, &cpus_hardware_enabled); + return r; +} + +static void hardware_enable(void *arg) +{ + atomic_t *failed =3D arg; + + if (__hardware_enable((void *)__func__)) + atomic_inc(failed); } =20 static void hardware_disable(void *junk) @@ -65,15 +68,16 @@ __weak void kvm_arch_pre_hardware_unsetup(void) */ __weak int kvm_arch_add_vm(struct kvm *kvm, int usage_count) { + atomic_t failed; int r =3D 0; =20 if (usage_count !=3D 1) return 0; =20 - atomic_set(&hardware_enable_failed, 0); - on_each_cpu(hardware_enable, (void *)__func__, 1); + atomic_set(&failed, 0); + on_each_cpu(hardware_enable, &failed, 1); =20 - if (atomic_read(&hardware_enable_failed)) { + if (atomic_read(&failed)) { r =3D -EBUSY; goto err; } @@ -96,33 +100,29 @@ __weak int kvm_arch_del_vm(int usage_count) =20 __weak int kvm_arch_online_cpu(unsigned int cpu, int usage_count) { - int ret =3D 0; + int ret; =20 ret =3D kvm_arch_check_processor_compat(); if (ret) return ret; =20 + if (!usage_count) + return 0; + + /* + * arch callback kvm_arch_hardware_eanble() assumes that + * preemption is disabled for historical reason. Disable + * preemption until all arch callbacks are fixed. + */ + preempt_disable(); /* * Abort the CPU online process if hardware virtualization cannot * be enabled. Otherwise running VMs would encounter unrecoverable * errors when scheduled to this CPU. */ - if (usage_count) { - WARN_ON_ONCE(atomic_read(&hardware_enable_failed)); + ret =3D __hardware_enable((void *)__func__); + preempt_enable(); =20 - /* - * arch callback kvm_arch_hardware_eanble() assumes that - * preemption is disabled for historical reason. Disable - * preemption until all arch callbacks are fixed. - */ - preempt_disable(); - hardware_enable((void *)__func__); - preempt_enable(); - if (atomic_read(&hardware_enable_failed)) { - atomic_set(&hardware_enable_failed, 0); - ret =3D -EIO; - } - } return ret; } =20 @@ -168,7 +168,7 @@ __weak void kvm_arch_resume(int usage_count) =20 if (usage_count) { preempt_disable(); - hardware_enable((void *)__func__); + (void)__hardware_enable((void *)__func__); preempt_enable(); } } --=20 2.25.1