From nobody Mon Feb 9 14:50:15 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1500236039254914.1213610527111; Sun, 16 Jul 2017 13:13:59 -0700 (PDT) Received: from localhost ([::1]:46739 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dWpvR-0000mV-Pp for importer@patchew.org; Sun, 16 Jul 2017 16:13:57 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46135) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dWpmZ-0001Al-Fi for qemu-devel@nongnu.org; Sun, 16 Jul 2017 16:04:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dWpmU-0008H2-Mu for qemu-devel@nongnu.org; Sun, 16 Jul 2017 16:04:47 -0400 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:48619) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dWpmU-0008G6-IB for qemu-devel@nongnu.org; Sun, 16 Jul 2017 16:04:42 -0400 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.nyi.internal (Postfix) with ESMTP id 9BADA20A4E; Sun, 16 Jul 2017 16:04:41 -0400 (EDT) Received: from frontend2 ([10.202.2.161]) by compute4.internal (MEProxy); Sun, 16 Jul 2017 16:04:41 -0400 Received: from localhost (flamenco.cs.columbia.edu [128.59.20.216]) by mail.messagingengine.com (Postfix) with ESMTPA id 6E8B7246A5; Sun, 16 Jul 2017 16:04:41 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=braap.org; h=cc :date:from:in-reply-to:message-id:references:subject:to :x-me-sender:x-me-sender:x-sasl-enc:x-sasl-enc; s=mesmtp; bh=CUb rzzm9aSiyRU+j82HvfE4OeX1m7RkRKhlK+iVROAo=; b=f97jp4zIRXEKnAGC/pe fjBZMAT0GbZ5QqmTB77xN87tDyLQX+aU7uODf+Ndu5aY3ST0k5pcve1HnuN54PzK 4uPRer+eUyCRSmVT2Er5j5i/sDL8e5vmKiNr8XEcb/kxXtxUv+pAzVVPjKi1qoAI a6IDze3E6Kuu1jeJX/BjvONM= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:date:from:in-reply-to:message-id :references:subject:to:x-me-sender:x-me-sender:x-sasl-enc :x-sasl-enc; s=fm1; bh=CUbrzzm9aSiyRU+j82HvfE4OeX1m7RkRKhlK+iVRO Ao=; b=V3ogcHHcpqqopOKj7CwQ0hSa6XLNxW3DP56gNuNzW2f7XMCPma4BPyjIV GfWJuJUTKA1GfSvbWCd7+OURKqb7jBp9TKjZXBotFGJkjihAKAUor1g3fSB2sBoG hqtp7NXgKB8e/W442VBL1+gJn/B3wdLNXr2Gh+y4qW9Pq8yUw1Tkt/dtWOWd0NT2 FhMPpT7B+hmdRJ2tNkocWikoyKw4ewqIaJOqKigvjsAXf7LoCLKBkLgUdzLsNOW1 nnLrpm5zeKmP+i3ioSRXFF1Lt698ySZXjPzLgKF1jm87Abyihr7+4D77xCD9CtNy +nczW3OdP8oAr6yh9vMtwjAL9tLpg== X-ME-Sender: X-Sasl-enc: 2RRA2M0/qliVdorj7RwoKPY0/ecQZinqY2+Tv9YE1JXk 1500235481 From: "Emilio G. Cota" To: qemu-devel@nongnu.org Date: Sun, 16 Jul 2017 16:03:53 -0400 Message-Id: <1500235468-15341-11-git-send-email-cota@braap.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1500235468-15341-1-git-send-email-cota@braap.org> References: <1500235468-15341-1-git-send-email-cota@braap.org> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.111.4.25 Subject: [Qemu-devel] [PATCH v2 10/45] translate-all: guarantee that tb_hash only holds valid TBs X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Richard Henderson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" This gets rid of the need to check the tb->invalid bit during lookups. After this change we do not need atomics to operate on tb->invalid: setting and checking its value is serialised with tb_lock. Signed-off-by: Emilio G. Cota --- accel/tcg/cpu-exec.c | 3 +-- accel/tcg/translate-all.c | 8 ++++++-- 2 files changed, 7 insertions(+), 4 deletions(-) diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c index c4c289b..9b5ce13 100644 --- a/accel/tcg/cpu-exec.c +++ b/accel/tcg/cpu-exec.c @@ -292,8 +292,7 @@ static bool tb_cmp(const void *p, const void *d) tb->page_addr[0] =3D=3D desc->phys_page1 && tb->cs_base =3D=3D desc->cs_base && tb->flags =3D=3D desc->flags && - tb->trace_vcpu_dstate =3D=3D desc->trace_vcpu_dstate && - !atomic_read(&tb->invalid)) { + tb->trace_vcpu_dstate =3D=3D desc->trace_vcpu_dstate) { /* check next page if needed */ if (tb->page_addr[1] =3D=3D -1) { return true; diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c index a124181..6d4c05f 100644 --- a/accel/tcg/translate-all.c +++ b/accel/tcg/translate-all.c @@ -1073,13 +1073,17 @@ void tb_phys_invalidate(TranslationBlock *tb, tb_pa= ge_addr_t page_addr) =20 assert_tb_locked(); =20 - atomic_set(&tb->invalid, true); - /* remove the TB from the hash list */ phys_pc =3D tb->page_addr[0] + (tb->pc & ~TARGET_PAGE_MASK); h =3D tb_hash_func(phys_pc, tb->pc, tb->flags, tb->trace_vcpu_dstate); qht_remove(&tcg_ctx.tb_ctx.htable, tb, h); =20 + /* + * Mark the TB as invalid *after* it's been removed from tb_hash, which + * eliminates the need to check this bit on lookups. + */ + tb->invalid =3D true; + /* remove the TB from the page list */ if (tb->page_addr[0] !=3D page_addr) { p =3D page_find(tb->page_addr[0] >> TARGET_PAGE_BITS); --=20 2.7.4