From patchwork Tue Mar 21 15:46:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Willgerodt, Felix" X-Patchwork-Id: 66700 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id AAA8F385735E for ; Tue, 21 Mar 2023 15:48:33 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org AAA8F385735E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1679413713; bh=SMwfxTcc8zH5IHrMcpzUN6qdES3GwCv/6fM6OQyyCY4=; h=To:Cc:Subject:Date:In-Reply-To:References:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From:Reply-To:From; b=XsGfxABx+s1fFy+iZZhWY1zezff14v7nJqCk10T6MrJoQRm9BmpHN1vep+CsxLcp0 PDd4OngMfScxAok1s3QV+aAU9If2wvygEJeEyfhUKhRxLCce2aml+5jFBCO8YDF1yA jIBmpSU2luCNpQ55yWdsHtrAA0CjsYQiSHU2N4O8= X-Original-To: gdb-patches@sourceware.org Delivered-To: gdb-patches@sourceware.org Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by sourceware.org (Postfix) with ESMTPS id 58D873858D3C for ; Tue, 21 Mar 2023 15:47:28 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 58D873858D3C X-IronPort-AV: E=McAfee;i="6600,9927,10656"; a="340517838" X-IronPort-AV: E=Sophos;i="5.98,279,1673942400"; d="scan'208";a="340517838" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Mar 2023 08:47:28 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10656"; a="681530395" X-IronPort-AV: E=Sophos;i="5.98,279,1673942400"; d="scan'208";a="681530395" Received: from mulfelix.iul.intel.com (HELO localhost) ([172.28.49.163]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Mar 2023 08:47:27 -0700 To: gdb-patches@sourceware.org Cc: Felix Willgerodt Subject: [PATCH v8 08/10] btrace, linux: Enable ptwrite packets. Date: Tue, 21 Mar 2023 16:46:24 +0100 Message-Id: <20230321154626.448816-9-felix.willgerodt@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230321154626.448816-1-felix.willgerodt@intel.com> References: <20230321154626.448816-1-felix.willgerodt@intel.com> MIME-Version: 1.0 X-Spam-Status: No, score=-10.3 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Felix Willgerodt via Gdb-patches From: "Willgerodt, Felix" Reply-To: Felix Willgerodt Errors-To: gdb-patches-bounces+patchwork=sourceware.org@sourceware.org Sender: "Gdb-patches" Enable ptwrite in the PT config, if it is supported by the kernel. --- gdb/nat/linux-btrace.c | 29 +++++++++++++++++++++++++++++ gdb/record-btrace.c | 5 +++++ 2 files changed, 34 insertions(+) diff --git a/gdb/nat/linux-btrace.c b/gdb/nat/linux-btrace.c index c5b3f1c93cf..e320eaa12ce 100644 --- a/gdb/nat/linux-btrace.c +++ b/gdb/nat/linux-btrace.c @@ -417,6 +417,29 @@ cpu_supports_bts (void) } } +/* Check whether the linux target supports Intel Processor Trace PTWRITE. */ + +static bool +linux_supports_ptwrite () +{ + static const char filename[] + = "/sys/bus/event_source/devices/intel_pt/caps/ptwrite"; + gdb_file_up file = gdb_fopen_cloexec (filename, "r"); + + if (file.get () == nullptr) + return false; + + int status, found = fscanf (file.get (), "%d", &status); + + if (found != 1) + { + warning (_("Failed to determine ptwrite support from %s."), filename); + return false; + } + + return status == 1; +} + /* The perf_event_open syscall failed. Try to print a helpful error message. */ @@ -626,6 +649,12 @@ linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf) pt->attr.exclude_hv = 1; pt->attr.exclude_idle = 1; + if (conf->ptwrite && linux_supports_ptwrite ()) + { + pt->attr.config |= 0x1000; + tinfo->conf.pt.ptwrite = conf->ptwrite; + } + errno = 0; scoped_fd fd (syscall (SYS_perf_event_open, &pt->attr, pid, -1, -1, 0)); if (fd.get () < 0) diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c index 22687e889ec..0b36ce5fdf6 100644 --- a/gdb/record-btrace.c +++ b/gdb/record-btrace.c @@ -3291,4 +3291,9 @@ to see the actual buffer size."), NULL, show_record_pt_buffer_size_value, record_btrace_conf.bts.size = 64 * 1024; record_btrace_conf.pt.size = 16 * 1024; +#if (LIBIPT_VERSION >= 0x200) + record_btrace_conf.pt.ptwrite = true; +#else + record_btrace_conf.pt.ptwrite = false; +#endif }