From nobody Wed Feb 5 15:48:43 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 B8D5D1465B4 for ; Mon, 20 Jan 2025 02:41:36 +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=1737340898; cv=none; b=mScMBisQHcLSTDqLs2iXBdzpF9EdoW9dPC88v1Sd5VL4NKwZDdLLyAKQMJ2Oh2C6H+pF2HIW7I44nSkzWFpFCwLCEviXUen6l4kHqRBMWu15neaqfsA3bZAUAJhqP/QHS2chN26/p0wwlXRlaFUZncUZXM5Muzm7wlbKXeyyfPI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737340898; c=relaxed/simple; bh=vw9hqg4DRdFNEWrC8T2F0fcGGBf4j6ryyXurgX143Kg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JO0vAdjbL8WSBNv+ceHbL7N9N8F8p89YJ3Crp7xV3lXV2hEN+8wxb4SudpsRe+ZANAEthGjQnbUUDxIuwjQEuGVd1MKX7Gj0oFyWNDVQNLE//Cz6pGtICbY2k95EgrZbKXmipt5YQoVU4M7h44TFtVTnXS6tpzD2iS9jfo3Gmys= 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 1tZhis-000000002w5-1hzA; Sun, 19 Jan 2025 21:41:06 -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, jannh@google.com, mhklinux@outlook.com, andrew.cooper3@citrix.com, Rik van Riel Subject: [PATCH v6 12/12] x86/mm: only invalidate final translations with INVLPGB Date: Sun, 19 Jan 2025 21:40:20 -0500 Message-ID: <20250120024104.1924753-13-riel@surriel.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250120024104.1924753-1-riel@surriel.com> References: <20250120024104.1924753-1-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" Use the INVLPGB_FINAL_ONLY flag when invalidating mappings with INVPLGB. This way only leaf mappings get removed from the TLB, leaving intermediate translations cached. On the (rare) occasions where we free page tables we do a full flush, ensuring intermediate translations get flushed from the TLB. Signed-off-by: Rik van Riel --- arch/x86/include/asm/invlpgb.h | 10 ++++++++-- arch/x86/mm/tlb.c | 8 ++++---- 2 files changed, 12 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/invlpgb.h b/arch/x86/include/asm/invlpgb.h index 4dfd09e65fa6..418402535319 100644 --- a/arch/x86/include/asm/invlpgb.h +++ b/arch/x86/include/asm/invlpgb.h @@ -63,9 +63,15 @@ static inline void invlpgb_flush_user(unsigned long pcid, static inline void invlpgb_flush_user_nr_nosync(unsigned long pcid, unsigned long addr, u16 nr, - bool pmd_stride) + bool pmd_stride, + bool freed_tables) { - __invlpgb(0, pcid, addr, nr - 1, pmd_stride, INVLPGB_PCID | INVLPGB_VA); + unsigned long flags =3D INVLPGB_PCID | INVLPGB_VA; + + if (!freed_tables) + flags |=3D INVLPGB_FINAL_ONLY; + + __invlpgb(0, pcid, addr, nr - 1, pmd_stride, flags); } =20 /* Flush all mappings for a given PCID, not including globals. */ diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index f731e6cfaa29..4057afb6edc0 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -538,10 +538,10 @@ static void broadcast_tlb_flush(struct flush_tlb_info= *info) nr =3D min(maxnr, (info->end - addr) >> info->stride_shift); nr =3D max(nr, 1); =20 - invlpgb_flush_user_nr_nosync(kern_pcid(asid), addr, nr, pmd); + invlpgb_flush_user_nr_nosync(kern_pcid(asid), addr, nr, pmd, info->freed= _tables); /* Do any CPUs supporting INVLPGB need PTI? */ if (static_cpu_has(X86_FEATURE_PTI)) - invlpgb_flush_user_nr_nosync(user_pcid(asid), addr, nr, pmd); + invlpgb_flush_user_nr_nosync(user_pcid(asid), addr, nr, pmd, info->free= d_tables); } =20 finish_asid_transition(info); @@ -1700,10 +1700,10 @@ void arch_tlbbatch_add_pending(struct arch_tlbflush= _unmap_batch *batch, batch->used_invlpgb =3D true; migrate_disable(); } - invlpgb_flush_user_nr_nosync(kern_pcid(asid), uaddr, 1, false); + invlpgb_flush_user_nr_nosync(kern_pcid(asid), uaddr, 1, false, false); /* Do any CPUs supporting INVLPGB need PTI? */ if (static_cpu_has(X86_FEATURE_PTI)) - invlpgb_flush_user_nr_nosync(user_pcid(asid), uaddr, 1, false); + invlpgb_flush_user_nr_nosync(user_pcid(asid), uaddr, 1, false, false); =20 /* * Some CPUs might still be using a local ASID for this --=20 2.47.1