From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 618 invoked by alias); 18 Aug 2013 19:06:11 -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 608 invoked by uid 89); 18 Aug 2013 19:06:11 -0000 X-Spam-SWARE-Status: No, score=-7.7 required=5.0 tests=AWL,BAYES_00,RCVD_IN_HOSTKARMA_W,RCVD_IN_HOSTKARMA_WL,RP_MATCHES_RCVD,SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.3.2 Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.84/v0.84-167-ge50287c) with ESMTP; Sun, 18 Aug 2013 19:06:11 +0000 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r7IJ69vW023344 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Sun, 18 Aug 2013 15:06:09 -0400 Received: from host2.jankratochvil.net (ovpn-116-37.ams2.redhat.com [10.36.116.37]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id r7IJ62IZ008291 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Sun, 18 Aug 2013 15:06:06 -0400 Date: Sun, 18 Aug 2013 19:06:00 -0000 From: Jan Kratochvil To: Markus Metzger Cc: gdb-patches@sourceware.org Subject: Re: [patch v4 06/24] btrace: increase buffer size Message-ID: <20130818190602.GE24153@host2.jankratochvil.net> References: <1372842874-28951-1-git-send-email-markus.t.metzger@intel.com> <1372842874-28951-7-git-send-email-markus.t.metzger@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1372842874-28951-7-git-send-email-markus.t.metzger@intel.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes X-SW-Source: 2013-08/txt/msg00461.txt.bz2 On Wed, 03 Jul 2013 11:14:16 +0200, Markus Metzger wrote: > Try to allocate as much buffer as we can for each thread with a maximum > of 4MB. > > 2013-07-03 Markus Metzger > > * common/linux-btrace.c (linux_enable_btrace): Increase buffer. Increase buffer size or Enlarge buffer. > > > --- > gdb/common/linux-btrace.c | 25 +++++++++++++++---------- > 1 files changed, 15 insertions(+), 10 deletions(-) > > diff --git a/gdb/common/linux-btrace.c b/gdb/common/linux-btrace.c > index b874c84..4880f41 100644 > --- a/gdb/common/linux-btrace.c > +++ b/gdb/common/linux-btrace.c > @@ -420,7 +420,7 @@ 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; > @@ -448,17 +448,22 @@ 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 = 10; 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: > -- > 1.7.1