From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E2B26CA0FED for ; Wed, 10 Sep 2025 18:13:02 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1uwPBR-0007yX-73; Wed, 10 Sep 2025 14:04:41 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1uwPBQ-0007yL-A3 for qemu-devel@nongnu.org; Wed, 10 Sep 2025 14:04:40 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1uwPBO-0004il-Ax for qemu-devel@nongnu.org; Wed, 10 Sep 2025 14:04:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1757527477; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ksiCewlUMa6gkJLmmfbF1PaSCeQGDxUBMFxmtS2Pb7A=; b=YVhArrZwAMZcH+yrDZ/zOy8CaGvgQhskJ3O/O4xSXJ5MXVEnOS7yyglEyLD+YbOMZACZbc 2UmTCK1kD5MaO/r85jfqt8ktNEUtD7R0YHq6iW3YMPhSDD0rmujth8qDvg+V+zEWW+YmzS Gp7XZuySWsNs0OV5//cSLJ/r2rg8cKw= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-454-grssG7fkO92Pr_7tNBOgbQ-1; Wed, 10 Sep 2025 14:04:35 -0400 X-MC-Unique: grssG7fkO92Pr_7tNBOgbQ-1 X-Mimecast-MFC-AGG-ID: grssG7fkO92Pr_7tNBOgbQ_1757527473 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 901001800452; Wed, 10 Sep 2025 18:04:33 +0000 (UTC) Received: from toolbx.redhat.com (unknown [10.42.28.57]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 8EE9D1800446; Wed, 10 Sep 2025 18:04:29 +0000 (UTC) From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, Hanna Reitz , Kevin Wolf , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Christian Schoenebeck , Richard Henderson , Manos Pitsidianakis , Stefan Weil , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Gerd Hoffmann , Paolo Bonzini , Markus Armbruster , "Dr. David Alan Gilbert" , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= Subject: [PATCH v3 07/20] util: add API to fetch the current thread name Date: Wed, 10 Sep 2025 19:03:44 +0100 Message-ID: <20250910180357.320297-8-berrange@redhat.com> In-Reply-To: <20250910180357.320297-1-berrange@redhat.com> References: <20250910180357.320297-1-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This will be used to include the thread name in error reports in a later patch. It returns a const string stored in a thread local to avoid memory allocation when it is called repeatedly in a single thread. This makes the assumption that the thread name is set at the very start of the thread, which is the case when using qemu_thread_create. Signed-off-by: Daniel P. Berrangé --- include/qemu/thread.h | 1 + meson.build | 21 +++++++++++++++++ util/qemu-thread-posix.c | 28 ++++++++++++++++++++++- util/qemu-thread-win32.c | 49 ++++++++++++++++++++++++++++++++++++---- 4 files changed, 94 insertions(+), 5 deletions(-) diff --git a/include/qemu/thread.h b/include/qemu/thread.h index 27b888ab0a..98cc5c41ac 100644 --- a/include/qemu/thread.h +++ b/include/qemu/thread.h @@ -216,6 +216,7 @@ void qemu_thread_get_self(QemuThread *thread); bool qemu_thread_is_self(QemuThread *thread); G_NORETURN void qemu_thread_exit(void *retval); void qemu_thread_set_name(const char *name); +const char *qemu_thread_get_name(void); struct Notifier; /** diff --git a/meson.build b/meson.build index fa6186db33..6aa673f4b2 100644 --- a/meson.build +++ b/meson.build @@ -2920,6 +2920,27 @@ config_host_data.set('CONFIG_PTHREAD_SET_NAME_NP', cc.links(osdep_prefix + ''' pthread_set_name_np(thread, "QEMU"); return 0; }''', dependencies: threads)) + +config_host_data.set('CONFIG_PTHREAD_GETNAME_NP', cc.links(osdep_prefix + ''' + #include + + int main(void) + { + char buf[16]; + pthread_getname_np(pthread_self(), buf, sizeof(buf)); + return 0; + }''', dependencies: threads)) +config_host_data.set('CONFIG_PTHREAD_GET_NAME_NP', cc.links(osdep_prefix + ''' + #include + #include + + int main(void) + { + char buf[16]; + pthread_get_name_np(pthread_self(), buf, sizeof(buf)); + return 0; + }''', dependencies: threads)) + config_host_data.set('CONFIG_PTHREAD_CONDATTR_SETCLOCK', cc.links(osdep_prefix + ''' #include diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c index 275445ed94..fbb94ca97b 100644 --- a/util/qemu-thread-posix.c +++ b/util/qemu-thread-posix.c @@ -18,7 +18,7 @@ #include "qemu/tsan.h" #include "qemu/bitmap.h" -#ifdef CONFIG_PTHREAD_SET_NAME_NP +#if defined(CONFIG_PTHREAD_SET_NAME_NP) || defined(CONFIG_PTHREAD_GET_NAME_NP) #include #endif @@ -532,3 +532,29 @@ void *qemu_thread_join(QemuThread *thread) } return ret; } + +#ifndef PTHREAD_MAX_NAMELEN_NP +#define PTHREAD_MAX_NAMELEN_NP 16 +#endif + +static __thread char namebuf[PTHREAD_MAX_NAMELEN_NP]; + +const char *qemu_thread_get_name(void) +{ + int rv; + if (namebuf[0] != '\0') { + return namebuf; + } + +# if defined(CONFIG_PTHREAD_GETNAME_NP) + rv = pthread_getname_np(pthread_self(), namebuf, sizeof(namebuf)); +# elif defined(CONFIG_PTHREAD_GET_NAME_NP) + rv = pthread_get_name_np(pthread_self(), namebuf, sizeof(namebuf)); +# else + rv = -1; +# endif + if (rv != 0) { + strlcpy(namebuf, "unnamed", G_N_ELEMENTS(namebuf)); + } + return namebuf; +} diff --git a/util/qemu-thread-win32.c b/util/qemu-thread-win32.c index 7a734a7a09..e3789c20d1 100644 --- a/util/qemu-thread-win32.c +++ b/util/qemu-thread-win32.c @@ -19,7 +19,10 @@ typedef HRESULT (WINAPI *pSetThreadDescription) (HANDLE hThread, PCWSTR lpThreadDescription); +typedef HRESULT (WINAPI *pGetThreadDescription) (HANDLE hThread, + PWSTR *lpThreadDescription); static pSetThreadDescription SetThreadDescriptionFunc; +static pGetThreadDescription GetThreadDescriptionFunc; static HMODULE kernel32_module; static void __attribute__((__constructor__(QEMU_CONSTRUCTOR_EARLY))) @@ -28,7 +31,7 @@ qemu_thread_init(void) qemu_thread_set_name("main"); } -static bool load_set_thread_description(void) +static bool load_thread_description(void) { static gsize _init_once = 0; @@ -38,14 +41,17 @@ static bool load_set_thread_description(void) SetThreadDescriptionFunc = (pSetThreadDescription)GetProcAddress(kernel32_module, "SetThreadDescription"); - if (!SetThreadDescriptionFunc) { + GetThreadDescriptionFunc = + (pGetThreadDescription)GetProcAddress(kernel32_module, + "GetThreadDescription"); + if (!SetThreadDescriptionFunc || !GetThreadDescriptionFunc) { FreeLibrary(kernel32_module); } } g_once_init_leave(&_init_once, 1); } - return !!SetThreadDescriptionFunc; + return !!(SetThreadDescriptionFunc && GetThreadDescriptionFunc); } static void error_exit(int err, const char *msg) @@ -326,7 +332,7 @@ void qemu_thread_set_name(const char *name) { g_autofree wchar_t *namew = NULL; - if (!load_set_thread_description()) { + if (!load_thread_description()) { return; } @@ -412,3 +418,38 @@ bool qemu_thread_is_self(QemuThread *thread) { return GetCurrentThreadId() == thread->tid; } + +static __thread char namebuf[64]; + +const char *qemu_thread_get_name(void) +{ + HRESULT hr; + wchar_t *namew = NULL; + g_autofree char *name = NULL; + + if (namebuf[0] != '\0') { + return namebuf; + } + + if (!load_thread_description()) { + goto error; + } + + hr = GetThreadDescriptionFunc(GetCurrentThread(), &namew); + if (!SUCCEEDED(hr)) { + goto error; + } + + name = g_utf16_to_utf8(namew, -1, NULL, NULL, NULL); + LocalFree(namew); + if (!name) { + goto error; + } + + g_strlcpy(namebuf, name, G_N_ELEMENTS(namebuf)); + return namebuf; + + error: + strlcpy(namebuf, "unnamed", G_N_ELEMENTS(namebuf)); + return namebuf; +} -- 2.50.1