Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964824Ab2EOBwt (ORCPT ); Mon, 14 May 2012 21:52:49 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:39780 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932708Ab2EOBwr (ORCPT ); Mon, 14 May 2012 21:52:47 -0400 Message-ID: <4FB1B6EA.1060206@gmail.com> Date: Mon, 14 May 2012 19:52:42 -0600 From: David Ahern User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: Arnaldo Carvalho de Melo , Namhyung Kim CC: linux-kernel@vger.kernel.org Subject: Re: [PATCH] perf-record: Create events initially disabled -- again References: <1336968088-11531-1-git-send-email-dsahern@gmail.com> <87sjf31a8c.fsf@sejong.aot.lge.com> <4FB1041C.1050903@gmail.com> <4FB114CE.10904@gmail.com> <20120514145416.GB4254@infradead.org> In-Reply-To: <20120514145416.GB4254@infradead.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5951 Lines: 154 On 5/14/12 8:54 AM, Arnaldo Carvalho de Melo wrote: > Em Mon, May 14, 2012 at 08:21:02AM -0600, David Ahern escreveu: >> On 5/14/12 7:09 AM, David Ahern wrote: >>>> A problem I see is that it'll break group handling again: >>>> >>>> $ ./perf stat -g sleep 1 >>>> >>>> Performance counter stats for 'sleep 1': >>>> >>>> task-clock >>>> context-switches >>>> CPU-migrations >>>> page-faults >>>> cycles >>>> stalled-cycles-frontend >>>> stalled-cycles-backend >>>> instructions >>>> branches >>>> branch-misses >>>> >>>> 1.000868932 seconds time elapsed >>>> >>>> So I suggest changing perf_target__none() check to a proper one >>>> (perf_target__no_cpu? - the name might be changed soon) for your >>>> purpose. >>> >>> Something else is wrong then. I tested that command (saw your patch in >>> the history) and it worked for me. Also, this code path does not affect >>> perf-stat -- it touches perf-record and perf-test only. >> >> I think it is something else. I am running latest git tree >> (3.4.0-rc7). perf from Linus' tree and acme/core both show: >> >> perf stat -g -- find /usr>/dev/null >> >> Performance counter stats for 'find /usr': >> >> task-clock >> context-switches >> CPU-migrations >> page-faults >> cycles >> stalled-cycles-frontend >> stalled-cycles-backend >> instructions >> branches >> branch-misses >> >> 0.111976940 seconds time elapsed >> >> (Using find to make sure some work is done as opposed to sleep; >> openssl speed also shows the above.) > > [acme@sandy ~]$ perf stat -g -- find /usr>/dev/null > find: `/usr/lib64/audit': Permission denied > ^Cfind: Interrupt > > Performance counter stats for 'find /usr': > > task-clock > context-switches > CPU-migrations > page-faults > cycles > stalled-cycles-frontend > stalled-cycles-backend > instructions > branches > branch-misses > > 1.282060271 seconds time elapsed > > > [acme@sandy ~]$ uname -r > 3.4.0-rc4-uprobes+ > > But: > > [acme@felicio linux]$ uname -r > 3.4.0-rc3+ > [acme@felicio linux]$ perf stat -g -- find /usr>/dev/null > ^Cfind: Interrupt > > Performance counter stats for 'find /usr': > > 126.499751 task-clock # 0.122 CPUs utilized > context-switches > CPU-migrations > page-faults > 366,694,182 cycles # 2.899 GHz > 151,332,137 stalled-cycles-frontend # 41.27% frontend cycles idle > 103,373,418 stalled-cycles-backend # 28.19% backend cycles idle > 408,309,250 instructions # 1.11 insns per cycle > # 0.37 stalled cycles > # per insn > 77,453,802 branches # 612.284 M/sec > 1,703,728 branch-misses # 2.20% of all branches > > 1.032917277 seconds time elapsed > > > [acme@felicio linux]$ > > Bisecting... > > - Arnaldo Seems like a few issues going on here. In all case the command run is: perf stat -g -- find / >/dev/null v3.1 kernel, v3.1 perf command -- command runs fine and generates output. v3.2 kernel, v3.2 perf command -- fails - no output and nothing in dmesg. Using latest acme/core version of perf generates a WARNING on all versions tried - v3.1, v3.2, v3.4-rc3, and v3.4-rc7: [ 143.964857] ------------[ cut here ]------------ [ 143.964870] WARNING: at /mnt/sw/kernels/kernel-2.6.git/arch/x86/kernel/cpu/perf_event.c:860 x86_pmu_start+0xdc/0x110() [ 143.964873] Hardware name: Bochs [ 143.964875] Modules linked in: lockd ip6t_REJECT nf_conntrack_ipv6 nf_conntrack_ipv4 nf_defrag_ipv6 nf_defrag_ipv4 xt_state nf_conntrack ip6table_filter ip6_tables ppdev parport_pc parport virtio_net i2c_piix4 i2c_core sunrpc virtio_blk [last unloaded: scsi_wait_scan] [ 143.964897] Pid: 968, comm: find Not tainted 3.2.0 #1 [ 143.964900] Call Trace: [ 143.964908] [] warn_slowpath_common+0x7f/0xc0 [ 143.964913] [] warn_slowpath_null+0x1a/0x20 [ 143.964917] [] x86_pmu_start+0xdc/0x110 [ 143.964921] [] x86_pmu_enable+0x212/0x270 [ 143.964928] [] perf_event_context_sched_in+0xe6/0x100 [ 143.964932] [] perf_event_comm+0x11e/0x330 [ 143.964940] [] ? get_random_int+0x74/0x90 [ 143.964947] [] set_task_comm+0x60/0x70 [ 143.964951] [] setup_new_exec+0xe1/0x2d0 [ 143.964958] [] load_elf_binary+0x3ec/0x1a10 [ 143.964972] [] ? get_user_pages+0x52/0x60 [ 143.964977] [] ? get_user_arg_ptr+0x38/0x80 [ 143.964982] [] search_binary_handler+0xec/0x300 [ 143.964986] [] ? do_mmap+0x40/0x40 [ 143.964990] [] do_execve_common+0x2ab/0x330 [ 143.964994] [] do_execve+0x3a/0x40 [ 143.964998] [] sys_execve+0x47/0x70 [ 143.965010] [] stub_execve+0x6c/0xc0 [ 143.965013] ---[ end trace 8de43f6b89ac81e1 ]--- David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/