From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31229 invoked by alias); 29 Nov 2013 14:39:38 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 31209 invoked by uid 89); 29 Nov 2013 14:39:37 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.0 required=5.0 tests=AWL,BAYES_20,RDNS_NONE,URIBL_BLOCKED autolearn=no version=3.3.2 X-HELO: mga09.intel.com Received: from Unknown (HELO mga09.intel.com) (134.134.136.24) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 29 Nov 2013 14:38:32 +0000 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP; 29 Nov 2013 06:34:43 -0800 X-ExtLoop1: 1 Received: from irvmail001.ir.intel.com ([163.33.26.43]) by orsmga002.jf.intel.com with ESMTP; 29 Nov 2013 06:38:21 -0800 Received: from ulvlx001.iul.intel.com (ulvlx001.iul.intel.com [172.28.207.17]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id rATEcLBG012337; Fri, 29 Nov 2013 14:38:21 GMT Received: from ulvlx001.iul.intel.com (localhost [127.0.0.1]) by ulvlx001.iul.intel.com with ESMTP id rATEcKWu012800; Fri, 29 Nov 2013 15:38:20 +0100 Received: (from mmetzger@localhost) by ulvlx001.iul.intel.com with œ id rATEcKSf012796; Fri, 29 Nov 2013 15:38:20 +0100 From: Markus Metzger To: jan.kratochvil@redhat.com Cc: gdb-patches@sourceware.org Subject: [patch v7 09/24] btrace: increase buffer size Date: Fri, 29 Nov 2013 14:39:00 -0000 Message-Id: <1385735899-12481-10-git-send-email-markus.t.metzger@intel.com> In-Reply-To: <1385735899-12481-1-git-send-email-markus.t.metzger@intel.com> References: <1385735899-12481-1-git-send-email-markus.t.metzger@intel.com> X-IsSubscribed: yes X-SW-Source: 2013-11/txt/msg00924.txt.bz2 Try to allocate as much buffer as we can for each thread with a maximum of 64KB. 2013-11-29 Markus Metzger * common/linux-btrace.c (linux_enable_btrace): Enlarge buffer. --- gdb/common/linux-btrace.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/gdb/common/linux-btrace.c b/gdb/common/linux-btrace.c index aa2b0ae..801505b 100644 --- a/gdb/common/linux-btrace.c +++ b/gdb/common/linux-btrace.c @@ -423,7 +423,7 @@ struct btrace_target_info * linux_enable_btrace (ptid_t ptid) { struct btrace_target_info *tinfo; - int pid; + int pid, pg; tinfo = xzalloc (sizeof (*tinfo)); tinfo->ptid = ptid; @@ -451,17 +451,22 @@ linux_enable_btrace (ptid_t ptid) if (tinfo->file < 0) goto err; - /* We hard-code the trace buffer size. - At some later time, we should make this configurable. */ - tinfo->size = 1; - tinfo->buffer = mmap (NULL, perf_event_mmap_size (tinfo), - PROT_READ, MAP_SHARED, tinfo->file, 0); - if (tinfo->buffer == MAP_FAILED) - goto err_file; + /* We try to allocate as much buffer as we can get. + We could allow the user to specify the size of the buffer, but then + we'd leave this search for the maximum buffer size to him. */ + for (pg = 4; pg >= 0; --pg) + { + /* The number of pages we request needs to be a power of two. */ + tinfo->size = 1 << pg; + tinfo->buffer = mmap (NULL, perf_event_mmap_size (tinfo), + PROT_READ, MAP_SHARED, tinfo->file, 0); + if (tinfo->buffer == MAP_FAILED) + continue; - return tinfo; + return tinfo; + } - err_file: + /* We were not able to allocate any buffer. */ close (tinfo->file); err: -- 1.8.3.1