From patchwork Wed May 7 18:22:26 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roman Kisel X-Patchwork-Id: 889417 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id D7E2C28E570; Wed, 7 May 2025 18:22:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746642151; cv=none; b=dCWm4cryGZ4Pd5N2uihE1EvLmynLrX7E4kw/nOMZ7YZTb7xMJgfFE6qXIjtdhknb3KZ2lgsU4ckivEPYTHLjXP6p5/u5RzuKu62bdFeGXZxIjYsDu4bk2R4tPpg3jF8v0q9nVv2bsXlzQ0i1rN31NnG70O61LffZD2uOYf3pFfI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746642151; c=relaxed/simple; bh=gOJoeDZBwYCGxNFcf1eQMv5TSPw3T23p54y9V5IxFTY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=P3bzyxK+csmiDTzNq9Tf1JFGJeYoR+RQP0HIiJPHWGngFn+LSqHACnUM92EbxY1e4xCm9CXc2VMD+J3EtAwTu17uHloCbX0Gx4tB/u56JeGSlH6roOKlgL8w64cikOFV/EXJBY30T9KddllWLB/9G8ZbmEnMyuT7VxbP28PDd0A= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=CJR5EipU; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="CJR5EipU" Received: from romank-3650.corp.microsoft.com (unknown [131.107.1.188]) by linux.microsoft.com (Postfix) with ESMTPSA id 38DAA2115DDF; Wed, 7 May 2025 11:22:29 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 38DAA2115DDF DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1746642149; bh=D1+Uvez//hmF/Wdt0SWl0vRh9x1zf/s+EcLLuID038E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CJR5EipUBL4dk/HQUZ71fX0AAFT7Y7BPw6V17bpVu3UujVHbwQeCZQWI2MOQjZhKw aXTb57a4EQyXlicJ1M65/KwtzyEvueSHWSZNTD6X0wTnqRRVZTqVMJIu39rygiEgWS XlDxTCdLQX5tIfeX6DCuheQN1UsYRijiSR8DTqYc= From: Roman Kisel To: ardb@kernel.org, bp@alien8.de, brgerst@gmail.com, dave.hansen@linux.intel.com, decui@microsoft.com, dimitri.sivanich@hpe.com, gautham.shenoy@amd.com, haiyangz@microsoft.com, hpa@zytor.com, imran.f.khan@oracle.com, jacob.jun.pan@linux.intel.com, jpoimboe@kernel.org, justin.ernst@hpe.com, kprateek.nayak@amd.com, kyle.meyer@hpe.com, kys@microsoft.com, lenb@kernel.org, mhklinux@outlook.com, mingo@redhat.com, nikunj@amd.com, papaluri@amd.com, patryk.wlazlyn@linux.intel.com, peterz@infradead.org, rafael@kernel.org, romank@linux.microsoft.com, russ.anderson@hpe.com, sohil.mehta@intel.com, steve.wahl@hpe.com, tglx@linutronix.de, thomas.lendacky@amd.com, tiala@microsoft.com, wei.liu@kernel.org, yuehaibing@huawei.com, linux-acpi@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org Cc: apais@microsoft.com, benhill@microsoft.com, bperkins@microsoft.com, sunilmut@microsoft.com Subject: [PATCH hyperv-next 2/2] arch/x86: Provide the CPU number in the wakeup AP callback Date: Wed, 7 May 2025 11:22:26 -0700 Message-ID: <20250507182227.7421-3-romank@linux.microsoft.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250507182227.7421-1-romank@linux.microsoft.com> References: <20250507182227.7421-1-romank@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 When starting APs, confidential guests and paravisor guests need to know the CPU number, and the pattern of using the linear search has emerged in several places. With N processors that leads to the O(N^2) time complexity. Provide the CPU number in the AP wake up callback so that one can get the CPU number in constant time. Suggested-by: Michael Kelley Signed-off-by: Roman Kisel Reviewed-by: Tom Lendacky Reviewed-by: Thomas Gleixner Reviewed-by: Michael Kelley --- arch/x86/coco/sev/core.c | 13 ++----------- arch/x86/hyperv/hv_vtl.c | 12 ++---------- arch/x86/hyperv/ivm.c | 15 ++------------- arch/x86/include/asm/apic.h | 8 ++++---- arch/x86/include/asm/mshyperv.h | 5 +++-- arch/x86/kernel/acpi/madt_wakeup.c | 2 +- arch/x86/kernel/apic/apic_noop.c | 8 +++++++- arch/x86/kernel/apic/apic_numachip.c | 2 +- arch/x86/kernel/apic/x2apic_uv_x.c | 2 +- arch/x86/kernel/smpboot.c | 10 +++++----- 10 files changed, 28 insertions(+), 49 deletions(-) diff --git a/arch/x86/coco/sev/core.c b/arch/x86/coco/sev/core.c index b0c1a7a57497..7780d55d1833 100644 --- a/arch/x86/coco/sev/core.c +++ b/arch/x86/coco/sev/core.c @@ -1177,7 +1177,7 @@ static void snp_cleanup_vmsa(struct sev_es_save_area *vmsa, int apic_id) free_page((unsigned long)vmsa); } -static int wakeup_cpu_via_vmgexit(u32 apic_id, unsigned long start_ip) +static int wakeup_cpu_via_vmgexit(u32 apic_id, unsigned long start_ip, unsigned int cpu) { struct sev_es_save_area *cur_vmsa, *vmsa; struct ghcb_state state; @@ -1185,7 +1185,7 @@ static int wakeup_cpu_via_vmgexit(u32 apic_id, unsigned long start_ip) unsigned long flags; struct ghcb *ghcb; u8 sipi_vector; - int cpu, ret; + int ret; u64 cr4; /* @@ -1206,15 +1206,6 @@ static int wakeup_cpu_via_vmgexit(u32 apic_id, unsigned long start_ip) /* Override start_ip with known protected guest start IP */ start_ip = real_mode_header->sev_es_trampoline_start; - - /* Find the logical CPU for the APIC ID */ - for_each_present_cpu(cpu) { - if (arch_match_cpu_phys_id(cpu, apic_id)) - break; - } - if (cpu >= nr_cpu_ids) - return -EINVAL; - cur_vmsa = per_cpu(sev_vmsa, cpu); /* diff --git a/arch/x86/hyperv/hv_vtl.c b/arch/x86/hyperv/hv_vtl.c index 2f32ac1ae40e..3d149a2ca4c8 100644 --- a/arch/x86/hyperv/hv_vtl.c +++ b/arch/x86/hyperv/hv_vtl.c @@ -211,17 +211,9 @@ static int hv_vtl_bringup_vcpu(u32 target_vp_index, int cpu, u64 eip_ignored) return ret; } -static int hv_vtl_wakeup_secondary_cpu(u32 apicid, unsigned long start_eip) +static int hv_vtl_wakeup_secondary_cpu(u32 apicid, unsigned long start_eip, unsigned int cpu) { - int vp_index, cpu; - - /* Find the logical CPU for the APIC ID */ - for_each_present_cpu(cpu) { - if (arch_match_cpu_phys_id(cpu, apicid)) - break; - } - if (cpu >= nr_cpu_ids) - return -EINVAL; + int vp_index; pr_debug("Bringing up CPU with APIC ID %d in VTL2...\n", apicid); vp_index = hv_apicid_to_vp_index(apicid); diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c index 0cc239cdb4da..e21557b24d19 100644 --- a/arch/x86/hyperv/ivm.c +++ b/arch/x86/hyperv/ivm.c @@ -289,7 +289,7 @@ static void snp_cleanup_vmsa(struct sev_es_save_area *vmsa) free_page((unsigned long)vmsa); } -int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip) +int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip, unsigned int cpu) { struct sev_es_save_area *vmsa = (struct sev_es_save_area *) __get_free_page(GFP_KERNEL | __GFP_ZERO); @@ -298,7 +298,7 @@ int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip) u64 ret, retry = 5; struct hv_enable_vp_vtl *start_vp_input; unsigned long flags; - int cpu, vp_index; + int vp_index; if (!vmsa) return -ENOMEM; @@ -308,17 +308,6 @@ int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip) if (vp_index < 0 || vp_index > ms_hyperv.max_vp_index) return -EINVAL; - /* - * Find the Linux CPU number for addressing the per-CPU data, and it - * might not be the same as APIC ID. - */ - for_each_present_cpu(cpu) { - if (arch_match_cpu_phys_id(cpu, apic_id)) - break; - } - if (cpu >= nr_cpu_ids) - return -EINVAL; - native_store_gdt(&gdtr); vmsa->gdtr.base = gdtr.address; diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h index c903d358405d..eaf43d446203 100644 --- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -313,9 +313,9 @@ struct apic { u32 (*get_apic_id)(u32 id); /* wakeup_secondary_cpu */ - int (*wakeup_secondary_cpu)(u32 apicid, unsigned long start_eip); + int (*wakeup_secondary_cpu)(u32 apicid, unsigned long start_eip, unsigned int cpu); /* wakeup secondary CPU using 64-bit wakeup point */ - int (*wakeup_secondary_cpu_64)(u32 apicid, unsigned long start_eip); + int (*wakeup_secondary_cpu_64)(u32 apicid, unsigned long start_eip, unsigned int cpu); char *name; }; @@ -333,8 +333,8 @@ struct apic_override { void (*send_IPI_self)(int vector); u64 (*icr_read)(void); void (*icr_write)(u32 low, u32 high); - int (*wakeup_secondary_cpu)(u32 apicid, unsigned long start_eip); - int (*wakeup_secondary_cpu_64)(u32 apicid, unsigned long start_eip); + int (*wakeup_secondary_cpu)(u32 apicid, unsigned long start_eip, unsigned int cpu); + int (*wakeup_secondary_cpu_64)(u32 apicid, unsigned long start_eip, unsigned int cpu); }; /* diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index 0b9a3a307d06..5ec92e3e2e37 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -268,11 +268,12 @@ int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_interrupt_entry *entry); #ifdef CONFIG_AMD_MEM_ENCRYPT bool hv_ghcb_negotiate_protocol(void); void __noreturn hv_ghcb_terminate(unsigned int set, unsigned int reason); -int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip); +int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip, unsigned int cpu); #else static inline bool hv_ghcb_negotiate_protocol(void) { return false; } static inline void hv_ghcb_terminate(unsigned int set, unsigned int reason) {} -static inline int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip) { return 0; } +static inline int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip, + unsigned int cpu) { return 0; } #endif #if defined(CONFIG_AMD_MEM_ENCRYPT) || defined(CONFIG_INTEL_TDX_GUEST) diff --git a/arch/x86/kernel/acpi/madt_wakeup.c b/arch/x86/kernel/acpi/madt_wakeup.c index f36f28405dcc..6d7603511f52 100644 --- a/arch/x86/kernel/acpi/madt_wakeup.c +++ b/arch/x86/kernel/acpi/madt_wakeup.c @@ -126,7 +126,7 @@ static int __init acpi_mp_setup_reset(u64 reset_vector) return 0; } -static int acpi_wakeup_cpu(u32 apicid, unsigned long start_ip) +static int acpi_wakeup_cpu(u32 apicid, unsigned long start_ip, unsigned int cpu) { if (!acpi_mp_wake_mailbox_paddr) { pr_warn_once("No MADT mailbox: cannot bringup secondary CPUs. Booting with kexec?\n"); diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c index b5bb7a2e8340..58abb941c45b 100644 --- a/arch/x86/kernel/apic/apic_noop.c +++ b/arch/x86/kernel/apic/apic_noop.c @@ -27,7 +27,13 @@ static void noop_send_IPI_allbutself(int vector) { } static void noop_send_IPI_all(int vector) { } static void noop_send_IPI_self(int vector) { } static void noop_apic_icr_write(u32 low, u32 id) { } -static int noop_wakeup_secondary_cpu(u32 apicid, unsigned long start_eip) { return -1; } + +static int noop_wakeup_secondary_cpu(u32 apicid, unsigned long start_eip, + unsigned int cpu) +{ + return -1; +} + static u64 noop_apic_icr_read(void) { return 0; } static u32 noop_get_apic_id(u32 apicid) { return 0; } static void noop_apic_eoi(void) { } diff --git a/arch/x86/kernel/apic/apic_numachip.c b/arch/x86/kernel/apic/apic_numachip.c index 16410f087b7a..333536b89bde 100644 --- a/arch/x86/kernel/apic/apic_numachip.c +++ b/arch/x86/kernel/apic/apic_numachip.c @@ -56,7 +56,7 @@ static void numachip2_apic_icr_write(int apicid, unsigned int val) numachip2_write32_lcsr(NUMACHIP2_APIC_ICR, (apicid << 12) | val); } -static int numachip_wakeup_secondary(u32 phys_apicid, unsigned long start_rip) +static int numachip_wakeup_secondary(u32 phys_apicid, unsigned long start_rip, unsigned int cpu) { numachip_apic_icr_write(phys_apicid, APIC_DM_INIT); numachip_apic_icr_write(phys_apicid, APIC_DM_STARTUP | diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c index 7fef504ca508..15209f220e1f 100644 --- a/arch/x86/kernel/apic/x2apic_uv_x.c +++ b/arch/x86/kernel/apic/x2apic_uv_x.c @@ -667,7 +667,7 @@ static __init void build_uv_gr_table(void) } } -static int uv_wakeup_secondary(u32 phys_apicid, unsigned long start_rip) +static int uv_wakeup_secondary(u32 phys_apicid, unsigned long start_rip, unsigned int cpu) { unsigned long val; int pnode; diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index d6cf1e23c2a3..d52e9238e9fd 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -695,7 +695,7 @@ static void send_init_sequence(u32 phys_apicid) /* * Wake up AP by INIT, INIT, STARTUP sequence. */ -static int wakeup_secondary_cpu_via_init(u32 phys_apicid, unsigned long start_eip) +static int wakeup_secondary_cpu_via_init(u32 phys_apicid, unsigned long start_eip, unsigned int cpu) { unsigned long send_status = 0, accept_status = 0; int num_starts, j, maxlvt; @@ -842,7 +842,7 @@ int common_cpu_up(unsigned int cpu, struct task_struct *idle) * Returns zero if startup was successfully sent, else error code from * ->wakeup_secondary_cpu. */ -static int do_boot_cpu(u32 apicid, int cpu, struct task_struct *idle) +static int do_boot_cpu(u32 apicid, unsigned int cpu, struct task_struct *idle) { unsigned long start_ip = real_mode_header->trampoline_start; int ret; @@ -896,11 +896,11 @@ static int do_boot_cpu(u32 apicid, int cpu, struct task_struct *idle) * - Use an INIT boot APIC message */ if (apic->wakeup_secondary_cpu_64) - ret = apic->wakeup_secondary_cpu_64(apicid, start_ip); + ret = apic->wakeup_secondary_cpu_64(apicid, start_ip, cpu); else if (apic->wakeup_secondary_cpu) - ret = apic->wakeup_secondary_cpu(apicid, start_ip); + ret = apic->wakeup_secondary_cpu(apicid, start_ip, cpu); else - ret = wakeup_secondary_cpu_via_init(apicid, start_ip); + ret = wakeup_secondary_cpu_via_init(apicid, start_ip, cpu); /* If the wakeup mechanism failed, cleanup the warm reset vector */ if (ret)