From nobody Fri Dec 19 08:06:34 2025 Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CF594383 for ; Wed, 26 Feb 2025 03:01:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=96.67.55.147 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740538908; cv=none; b=pJUosFmSJs8dpNtRji3p/DR+5cTMx7UXDwE9fAO7MzPeuSOpffwryeehC8nA7mbuuHS4ecwmuCom8jGku7jEylleSgpRcc82ILoeds92S3tWbNVR8kT9u+2Pt/flDd1497QGtT2BCRL8QoiLgktITs9o1C4qEJ2NFTaHTEf7/9Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740538908; c=relaxed/simple; bh=vv2yc3xS3j1KYZ0Dh7ly7vBxVn3c1CiltbqqzFemO+A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uHXB3pdXQ0jbD7Fko62atUR2N5//dNWbVDp2h0Zp+xF9JKoUQi7I3MkeEa5pyxdZHKmD4OD90JnW2rxw5F0MAhyiW4E+7Syff73lbiaAVwOvJy2qIfgswrIBBJglVAN7pSskwqMSBYPjiIy4KA5485fNsUyiHIvPKW2P+Lf4rTc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=surriel.com; spf=pass smtp.mailfrom=shelob.surriel.com; arc=none smtp.client-ip=96.67.55.147 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=surriel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=shelob.surriel.com Received: from fangorn.home.surriel.com ([10.0.13.7]) by shelob.surriel.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.97.1) (envelope-from ) id 1tn7fw-000000001Y5-0aUg; Tue, 25 Feb 2025 22:01:32 -0500 From: Rik van Riel To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, bp@alien8.de, peterz@infradead.org, dave.hansen@linux.intel.com, zhengqi.arch@bytedance.com, nadav.amit@gmail.com, thomas.lendacky@amd.com, kernel-team@meta.com, linux-mm@kvack.org, akpm@linux-foundation.org, jackmanb@google.com, jannh@google.com, mhklinux@outlook.com, andrew.cooper3@citrix.com, Manali.Shukla@amd.com, mingo@kernel.org, Rik van Riel , Dave Hansen Subject: [PATCH v14 03/13] x86/mm: add INVLPGB support code Date: Tue, 25 Feb 2025 22:00:38 -0500 Message-ID: <20250226030129.530345-4-riel@surriel.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250226030129.530345-1-riel@surriel.com> References: <20250226030129.530345-1-riel@surriel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: riel@surriel.com Content-Type: text/plain; charset="utf-8" Add helper functions and definitions needed to use broadcast TLB invalidation on AMD EPYC 3 and newer CPUs. All the functions defined in invlpgb.h are used later in the series. Compile time disabling X86_FEATURE_INVLPGB when the config option is not set allows the compiler to omit unnecessary code. Signed-off-by: Rik van Riel Tested-by: Manali Shukla Tested-by: Brendan Jackman Tested-by: Michael Kelley Acked-by: Dave Hansen --- arch/x86/include/asm/disabled-features.h | 8 +- arch/x86/include/asm/tlb.h | 98 ++++++++++++++++++++++++ 2 files changed, 105 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/as= m/disabled-features.h index c492bdc97b05..625a89259968 100644 --- a/arch/x86/include/asm/disabled-features.h +++ b/arch/x86/include/asm/disabled-features.h @@ -129,6 +129,12 @@ #define DISABLE_SEV_SNP (1 << (X86_FEATURE_SEV_SNP & 31)) #endif =20 +#ifdef CONFIG_X86_BROADCAST_TLB_FLUSH +#define DISABLE_INVLPGB 0 +#else +#define DISABLE_INVLPGB (1 << (X86_FEATURE_INVLPGB & 31)) +#endif + /* * Make sure to add features to the correct mask */ @@ -146,7 +152,7 @@ #define DISABLED_MASK11 (DISABLE_RETPOLINE|DISABLE_RETHUNK|DISABLE_UNRET| \ DISABLE_CALL_DEPTH_TRACKING|DISABLE_USER_SHSTK) #define DISABLED_MASK12 (DISABLE_FRED|DISABLE_LAM) -#define DISABLED_MASK13 0 +#define DISABLED_MASK13 (DISABLE_INVLPGB) #define DISABLED_MASK14 0 #define DISABLED_MASK15 0 #define DISABLED_MASK16 (DISABLE_PKU|DISABLE_OSPKE|DISABLE_LA57|DISABLE_UM= IP| \ diff --git a/arch/x86/include/asm/tlb.h b/arch/x86/include/asm/tlb.h index 77f52bc1578a..91c9a4da3ace 100644 --- a/arch/x86/include/asm/tlb.h +++ b/arch/x86/include/asm/tlb.h @@ -6,6 +6,9 @@ static inline void tlb_flush(struct mmu_gather *tlb); =20 #include +#include +#include +#include =20 static inline void tlb_flush(struct mmu_gather *tlb) { @@ -25,4 +28,99 @@ static inline void invlpg(unsigned long addr) asm volatile("invlpg (%0)" ::"r" (addr) : "memory"); } =20 + +/* + * INVLPGB does broadcast TLB invalidation across all the CPUs in the syst= em. + * + * The INVLPGB instruction is weakly ordered, and a batch of invalidations= can + * be done in a parallel fashion. + * + * The instruction takes the number of extra pages to invalidate, beyond + * the first page, while __invlpgb gets the more human readable number of + * pages to invalidate. + * + * TLBSYNC is used to ensure that pending INVLPGB invalidations initiated = from + * this CPU have completed. + */ +static inline void __invlpgb(unsigned long asid, unsigned long pcid, + unsigned long addr, u16 nr_pages, + bool pmd_stride, u8 flags) +{ + u32 edx =3D (pcid << 16) | asid; + u32 ecx =3D (pmd_stride << 31) | (nr_pages - 1); + u64 rax =3D addr | flags; + + /* The low bits in rax are for flags. Verify addr is clean. */ + VM_WARN_ON_ONCE(addr & ~PAGE_MASK); + + /* INVLPGB; supported in binutils >=3D 2.36. */ + asm volatile(".byte 0x0f, 0x01, 0xfe" : : "a" (rax), "c" (ecx), "d" (edx)= ); +} + +static inline void __tlbsync(void) +{ + /* + * tlbsync waits for invlpgb instructions originating on the + * same CPU to have completed. Print a warning if we could have + * migrated, and might not be waiting on all the invlpgbs issued + * during this TLB invalidation sequence. + */ + cant_migrate(); + + /* TLBSYNC: supported in binutils >=3D 0.36. */ + asm volatile(".byte 0x0f, 0x01, 0xff" ::: "memory"); +} + +/* + * INVLPGB can be targeted by virtual address, PCID, ASID, or any combinat= ion + * of the three. For example: + * - INVLPGB_VA | INVLPGB_INCLUDE_GLOBAL: invalidate all TLB entries at th= e address + * - INVLPGB_PCID: invalidate all TLB entries matching the PCID + * + * The first can be used to invalidate (kernel) mappings at a particular + * address across all processes. + * + * The latter invalidates all TLB entries matching a PCID. + */ +#define INVLPGB_VA BIT(0) +#define INVLPGB_PCID BIT(1) +#define INVLPGB_ASID BIT(2) +#define INVLPGB_INCLUDE_GLOBAL BIT(3) +#define INVLPGB_FINAL_ONLY BIT(4) +#define INVLPGB_INCLUDE_NESTED BIT(5) + +static inline void invlpgb_flush_user_nr_nosync(unsigned long pcid, + unsigned long addr, + u16 nr, + bool pmd_stride) +{ + __invlpgb(0, pcid, addr, nr, pmd_stride, INVLPGB_PCID | INVLPGB_VA); +} + +/* Flush all mappings for a given PCID, not including globals. */ +static inline void invlpgb_flush_single_pcid_nosync(unsigned long pcid) +{ + __invlpgb(0, pcid, 0, 1, 0, INVLPGB_PCID); +} + +/* Flush all mappings, including globals, for all PCIDs. */ +static inline void invlpgb_flush_all(void) +{ + __invlpgb(0, 0, 0, 1, 0, INVLPGB_INCLUDE_GLOBAL); + __tlbsync(); +} + +/* Flush addr, including globals, for all PCIDs. */ +static inline void invlpgb_flush_addr_nosync(unsigned long addr, u16 nr) +{ + __invlpgb(0, 0, addr, nr, 0, INVLPGB_INCLUDE_GLOBAL); +} + +/* Flush all mappings for all PCIDs except globals. */ +static inline void invlpgb_flush_all_nonglobals(void) +{ + __invlpgb(0, 0, 0, 1, 0, 0); + __tlbsync(); +} + #endif /* _ASM_X86_TLB_H */ --=20 2.47.1