From patchwork Sun Jan 22 02:46:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tianyu Lan X-Patchwork-Id: 13111402 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 4131BC54EB4 for ; Sun, 22 Jan 2023 02:47:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230167AbjAVCr6 (ORCPT ); Sat, 21 Jan 2023 21:47:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56242 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229920AbjAVCrW (ORCPT ); Sat, 21 Jan 2023 21:47:22 -0500 Received: from mail-pj1-x102c.google.com (mail-pj1-x102c.google.com [IPv6:2607:f8b0:4864:20::102c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8543A24481; Sat, 21 Jan 2023 18:46:42 -0800 (PST) Received: by mail-pj1-x102c.google.com with SMTP id h5-20020a17090a9c0500b0022bb85eb35dso3944605pjp.3; Sat, 21 Jan 2023 18:46:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; 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=HfzaNmMXTvYjZaqBx5BRGh5/YKdqJuGZMdeNixaODzI=; b=CftyTjTfQaZlq6X+W/d9ddvb3E7GIsvuW56grnwYN/kjL2hPuns+Lv2zmf17h+Bz80 gbHbRV1L8cabmqUYsjDWnLabuuY3Fs2fdwyNow7dZX5lYjA7hJmqoT1VL4JTMZwgf/iP xRTEsQOgqV0xsq+8+EjD22xPS0quK+jPa6L/Sy1KHJjQ+yHsp92f12rKF4U9gBbT2b9r gxvd53MiamSbL1spRy4c3k01MsHuL/cZQKZ8cO5DUN7B2AZQQFJ3RUYYXXw9gx4VS7mW BZA9YUfo9CWDXAMW8z4+5ZBTnla0ngLZLEzfeZ02prI0eganSll9A3Z4+ob8VlwpmvTp d6hg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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=HfzaNmMXTvYjZaqBx5BRGh5/YKdqJuGZMdeNixaODzI=; b=sysE2oWkeupsYkoczfiePeBYTgchXDICspFd8cEqnveBs5iYg43/k7L+G1RHymQu21 DvpzhDpi8b6n1rdcwMJUomqssvDGvOYAtZJPeAais7jQdCfOkpv7bRcWAQxeHNw33+f+ +ONHlsfTIl7JA5sfsORG4/GlzijmUpYAtWctk1pnDlMghJCckNj0Z1PXmVU+KUx3KDVa yvy3JTwfFaMG9NFuRifvMDWUmVS78K/0sLk1up23ua/FMgQ2dHsqu/KyRcXIWuRxVo5f vs5vaO6BijxxAL9Dg4NbgIQA+0YTnVBdV//DvHxQ6BbYL04syxPAOZhN0Pc+VDHwDSNw fzhQ== X-Gm-Message-State: AFqh2koMMVk6CeTfb4Zk4uZ1K3lrjodqjlVeF1/Dipuz3GnTnIdQhJbN HUOeBKR40ZldSWT4SODa6sQ= X-Google-Smtp-Source: AMrXdXueHgf+64MbPOvUl3iPQC56zhsQqJoJWPq4Yf/nM88fQTLxW966nL9hfBqm61ZqY3d5YnD66Q== X-Received: by 2002:a05:6a21:1646:b0:ac:29b4:11bc with SMTP id no6-20020a056a21164600b000ac29b411bcmr19655447pzb.21.1674355592364; Sat, 21 Jan 2023 18:46:32 -0800 (PST) Received: from ubuntu-Virtual-Machine.corp.microsoft.com ([2001:4898:80e8:36:d4:8b9d:a9e7:109b]) by smtp.gmail.com with ESMTPSA id b75-20020a621b4e000000b0058ba53aaa75sm18523094pfb.99.2023.01.21.18.46.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 21 Jan 2023 18:46:31 -0800 (PST) From: Tianyu Lan To: luto@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, seanjc@google.com, pbonzini@redhat.com, jgross@suse.com, tiala@microsoft.com, kirill@shutemov.name, jiangshan.ljs@antgroup.com, peterz@infradead.org, ashish.kalra@amd.com, srutherford@google.com, akpm@linux-foundation.org, anshuman.khandual@arm.com, pawan.kumar.gupta@linux.intel.com, adrian.hunter@intel.com, daniel.sneddon@linux.intel.com, alexander.shishkin@linux.intel.com, sandipan.das@amd.com, ray.huang@amd.com, brijesh.singh@amd.com, michael.roth@amd.com, thomas.lendacky@amd.com, venu.busireddy@oracle.com, sterritt@google.com, tony.luck@intel.com, samitolvanen@google.com, fenghua.yu@intel.com Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arch@vger.kernel.org Subject: [RFC PATCH V3 15/16] x86/sev: optimize system vector processing invoked from #HV exception Date: Sat, 21 Jan 2023 21:46:05 -0500 Message-Id: <20230122024607.788454-16-ltykernel@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230122024607.788454-1-ltykernel@gmail.com> References: <20230122024607.788454-1-ltykernel@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Ashish Kalra Construct system vector table and dispatch system vector exceptions through sysvec_table from #HV exception handler instead of explicitly calling each system vector. The system vector table is created dynamically and is placed in a new named ELF section. Signed-off-by: Ashish Kalra --- arch/x86/entry/entry_64.S | 6 +++ arch/x86/kernel/sev.c | 70 +++++++++++++---------------------- arch/x86/kernel/vmlinux.lds.S | 7 ++++ 3 files changed, 38 insertions(+), 45 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index aec8dc4443d1..03af871f08e9 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -412,6 +412,12 @@ SYM_CODE_START(\asmsym) _ASM_NOKPROBE(\asmsym) SYM_CODE_END(\asmsym) + .if \vector >= FIRST_SYSTEM_VECTOR && \vector < NR_VECTORS + .section .system_vectors, "aw" + .byte \vector + .quad \cfunc + .previous + .endif .endm /* diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index 03d99fad9e76..b1a98c2a52f8 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -151,6 +151,16 @@ struct sev_snp_runtime_data { static DEFINE_PER_CPU(struct sev_snp_runtime_data*, snp_runtime_data); +static void (*sysvec_table[NR_VECTORS - FIRST_SYSTEM_VECTOR]) + (struct pt_regs *regs) __ro_after_init; + +struct sysvec_entry { + unsigned char vector; + void (*sysvec_func)(struct pt_regs *regs); +} __packed; + +extern struct sysvec_entry __system_vectors[], __system_vectors_end[]; + static inline u64 sev_es_rd_ghcb_msr(void) { return __rdmsr(MSR_AMD64_SEV_ES_GHCB); @@ -214,51 +224,11 @@ static void do_exc_hv(struct pt_regs *regs) } else if (pending_events.vector == IA32_SYSCALL_VECTOR) { WARN(1, "syscall shouldn't happen\n"); } else if (pending_events.vector >= FIRST_SYSTEM_VECTOR) { - switch (pending_events.vector) { -#if IS_ENABLED(CONFIG_HYPERV) - case HYPERV_STIMER0_VECTOR: - sysvec_hyperv_stimer0(regs); - break; - case HYPERVISOR_CALLBACK_VECTOR: - sysvec_hyperv_callback(regs); - break; -#endif -#ifdef CONFIG_SMP - case RESCHEDULE_VECTOR: - sysvec_reschedule_ipi(regs); - break; - case IRQ_MOVE_CLEANUP_VECTOR: - sysvec_irq_move_cleanup(regs); - break; - case REBOOT_VECTOR: - sysvec_reboot(regs); - break; - case CALL_FUNCTION_SINGLE_VECTOR: - sysvec_call_function_single(regs); - break; - case CALL_FUNCTION_VECTOR: - sysvec_call_function(regs); - break; -#endif -#ifdef CONFIG_X86_LOCAL_APIC - case ERROR_APIC_VECTOR: - sysvec_error_interrupt(regs); - break; - case SPURIOUS_APIC_VECTOR: - sysvec_spurious_apic_interrupt(regs); - break; - case LOCAL_TIMER_VECTOR: - sysvec_apic_timer_interrupt(regs); - break; - case X86_PLATFORM_IPI_VECTOR: - sysvec_x86_platform_ipi(regs); - break; -#endif - case 0x0: - break; - default: - panic("Unexpected vector %d\n", vector); - unreachable(); + if (!(sysvec_table[pending_events.vector - FIRST_SYSTEM_VECTOR])) { + WARN(1, "system vector entry 0x%x is NULL\n", + pending_events.vector); + } else { + (*sysvec_table[pending_events.vector - FIRST_SYSTEM_VECTOR])(regs); } } else { common_interrupt(regs, pending_events.vector); @@ -376,6 +346,14 @@ static bool sev_restricted_injection_enabled(void) return sev_status & MSR_AMD64_SEV_RESTRICTED_INJECTION_ENABLED; } +static void __init construct_sysvec_table(void) +{ + struct sysvec_entry *p; + + for (p = __system_vectors; p < __system_vectors_end; p++) + sysvec_table[p->vector - FIRST_SYSTEM_VECTOR] = p->sysvec_func; +} + void __init sev_snp_init_hv_handling(void) { struct sev_snp_runtime_data *snp_data; @@ -403,6 +381,8 @@ void __init sev_snp_init_hv_handling(void) apic_set_eoi_write(hv_doorbell_apic_eoi_write); local_irq_restore(flags); + + construct_sysvec_table(); } static int vc_fetch_insn_kernel(struct es_em_ctxt *ctxt, diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 2e0ee14229bf..aeadb4754b00 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -339,6 +339,13 @@ SECTIONS *(.altinstr_replacement) } + . = ALIGN(8); + .system_vectors : AT(ADDR(.system_vectors) - LOAD_OFFSET) { + __system_vectors = .; + *(.system_vectors) + __system_vectors_end = .; + } + . = ALIGN(8); .apicdrivers : AT(ADDR(.apicdrivers) - LOAD_OFFSET) { __apicdrivers = .;