From nobody Tue Feb 10 06:58:27 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=ispras.ru Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1636624606504747.0933654802667; Thu, 11 Nov 2021 01:56:46 -0800 (PST) Received: from localhost ([::1]:41638 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ml6p3-0000sA-6W for importer@patchew.org; Thu, 11 Nov 2021 04:56:45 -0500 Received: from eggs.gnu.org ([209.51.188.92]:33960) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ml6nZ-0007JN-Ci for qemu-devel@nongnu.org; Thu, 11 Nov 2021 04:55:14 -0500 Received: from mail.ispras.ru ([83.149.199.84]:44968) by eggs.gnu.org with esmtps (TLS1.2:DHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ml6nX-0008OB-Dv for qemu-devel@nongnu.org; Thu, 11 Nov 2021 04:55:13 -0500 Received: from [127.0.1.1] (unknown [85.142.117.226]) by mail.ispras.ru (Postfix) with ESMTPSA id 1D48740755CE; Thu, 11 Nov 2021 09:55:09 +0000 (UTC) Subject: [PATCH v2 1/3] icount: preserve cflags when custom tb is about to execute From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Thu, 11 Nov 2021 12:55:08 +0300 Message-ID: <163662450891.125458.6706022775465303586.stgit@pasha-ThinkPad-X280> In-Reply-To: <163662450348.125458.5494710452733592356.stgit@pasha-ThinkPad-X280> References: <163662450348.125458.5494710452733592356.stgit@pasha-ThinkPad-X280> User-Agent: StGit/0.23 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=83.149.199.84; envelope-from=pavel.dovgalyuk@ispras.ru; helo=mail.ispras.ru X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: pavel.dovgalyuk@ispras.ru, david@redhat.com, richard.henderson@linaro.org, peterx@redhat.com, pbonzini@redhat.com, alex.bennee@linaro.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZM-MESSAGEID: 1636624608854100003 When debugging with the watchpoints, qemu may need to create TB with single instruction. This is achieved by setting cpu->cflags_next_tb. But when this block is about to execute, it may be interrupted by another thread. In this case cflags will be lost and next executed TB will not be the special one. This patch checks TB exit reason and restores cflags_next_tb to allow finding the interrupted block. Signed-off-by: Pavel Dovgalyuk --- accel/tcg/cpu-exec.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c index 2d14d02f6c..df12452b8f 100644 --- a/accel/tcg/cpu-exec.c +++ b/accel/tcg/cpu-exec.c @@ -846,6 +846,16 @@ static inline void cpu_loop_exec_tb(CPUState *cpu, Tra= nslationBlock *tb, * cpu_handle_interrupt. cpu_handle_interrupt will also * clear cpu->icount_decr.u16.high. */ + if (cpu->cflags_next_tb =3D=3D -1 + && (!use_icount || !(tb->cflags & CF_USE_ICOUNT) + || cpu_neg(cpu)->icount_decr.u16.low >=3D tb->icount)) { + /* + * icount is disabled or there are enough instructions + * in the budget, do not retranslate this block with + * different parameters. + */ + cpu->cflags_next_tb =3D tb->cflags; + } return; } =20