From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965160AbcALKxo (ORCPT ); Tue, 12 Jan 2016 05:53:44 -0500 Received: from mail-qk0-f193.google.com ([209.85.220.193]:36821 "EHLO mail-qk0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964926AbcALKxj (ORCPT ); Tue, 12 Jan 2016 05:53:39 -0500 MIME-Version: 1.0 X-Originating-IP: [195.54.192.103] In-Reply-To: <20151223111228.10f25239@gandalf.local.home> References: <1450124286-4822-1-git-send-email-kda@linux-powerpc.org> <1450124286-4822-2-git-send-email-kda@linux-powerpc.org> <20151223111228.10f25239@gandalf.local.home> Date: Tue, 12 Jan 2016 13:53:38 +0300 Message-ID: Subject: Re: [PATCH v3 2/2] powerpc: tracing: don't trace hcalls on offline CPUs From: Denis Kirjanov To: Michael Ellerman Cc: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, Steven Rostedt Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/23/15, Steven Rostedt wrote: > On Mon, 14 Dec 2015 23:18:06 +0300 > Denis Kirjanov wrote: > >> ./drmgr -c cpu -a -r gives the following warning: >> >> [ 2327.035563] >> RCU used illegally from offline CPU! >> rcu_scheduler_active = 1, debug_locks = 1 >> [ 2327.035564] no locks held by swapper/12/0. >> [ 2327.035565] >> stack backtrace: >> [ 2327.035567] CPU: 12 PID: 0 Comm: swapper/12 Tainted: G S >> 4.3.0-rc3-00060-g353169a #5 >> [ 2327.035568] Call Trace: >> [ 2327.035573] [c0000001d62578e0] [c0000000008977fc] .dump_stack+0x98/0xd4 >> (unreliable) >> [ 2327.035577] [c0000001d6257960] [c000000000109bd8] >> .lockdep_rcu_suspicious+0x108/0x170 >> [ 2327.035580] [c0000001d62579f0] [c00000000006a1d0] >> .__trace_hcall_exit+0x2b0/0x2c0 >> [ 2327.035584] [c0000001d6257ab0] [c00000000006a2e8] >> plpar_hcall_norets_trace+0x70/0x8c >> [ 2327.035588] [c0000001d6257b20] [c000000000067a14] >> .icp_hv_set_cpu_priority+0x54/0xc0 >> [ 2327.035592] [c0000001d6257ba0] [c000000000066c5c] >> .xics_teardown_cpu+0x5c/0xa0 >> [ 2327.035595] [c0000001d6257c20] [c0000000000747ac] >> .pseries_mach_cpu_die+0x6c/0x320 >> [ 2327.035598] [c0000001d6257cd0] [c0000000000439cc] .cpu_die+0x3c/0x60 >> [ 2327.035602] [c0000001d6257d40] [c0000000000183d8] >> .arch_cpu_idle_dead+0x28/0x40 >> [ 2327.035606] [c0000001d6257db0] [c0000000000ff1dc] >> .cpu_startup_entry+0x4fc/0x560 >> [ 2327.035610] [c0000001d6257ed0] [c000000000043728] >> .start_secondary+0x328/0x360 >> [ 2327.035614] [c0000001d6257f90] [c000000000008a6c] >> start_secondary_prolog+0x10/0x14 >> [ 2327.035620] cpu 12 (hwid 12) Ready to die... >> [ 2327.144463] cpu 13 (hwid 13) Ready to die... >> [ 2327.294180] cpu 14 (hwid 14) Ready to die... >> [ 2327.403599] cpu 15 (hwid 15) Ready to die... >> >> Make the hypervisor tracepoints conditional >> by using TRACE_EVENT_FN_COND >> >> Signed-off-by: Denis Kirjanov > > I applied the first patch, but I need Acks from the powerpc maintainers > to take this one. > Hi Michael, Could you please put your ack to the second patch. Thanks! > -- Steve > > >> >> v2 changes: >> - Use raw_smp_processor_id as suggested by BenH >> since since hcalls can be called from preemptable sections >> >> v3 changes: >> - Fix the subject line >> --- >> arch/powerpc/include/asm/trace.h | 8 ++++++-- >> 1 file changed, 6 insertions(+), 2 deletions(-) >> >> diff --git a/arch/powerpc/include/asm/trace.h >> b/arch/powerpc/include/asm/trace.h >> index 8e86b48..32e36b1 100644 >> --- a/arch/powerpc/include/asm/trace.h >> +++ b/arch/powerpc/include/asm/trace.h >> @@ -57,12 +57,14 @@ DEFINE_EVENT(ppc64_interrupt_class, >> timer_interrupt_exit, >> extern void hcall_tracepoint_regfunc(void); >> extern void hcall_tracepoint_unregfunc(void); >> >> -TRACE_EVENT_FN(hcall_entry, >> +TRACE_EVENT_FN_COND(hcall_entry, >> >> TP_PROTO(unsigned long opcode, unsigned long *args), >> >> TP_ARGS(opcode, args), >> >> + TP_CONDITION(cpu_online(raw_smp_processor_id())), >> + >> TP_STRUCT__entry( >> __field(unsigned long, opcode) >> ), >> @@ -76,13 +78,15 @@ TRACE_EVENT_FN(hcall_entry, >> hcall_tracepoint_regfunc, hcall_tracepoint_unregfunc >> ); >> >> -TRACE_EVENT_FN(hcall_exit, >> +TRACE_EVENT_FN_COND(hcall_exit, >> >> TP_PROTO(unsigned long opcode, unsigned long retval, >> unsigned long *retbuf), >> >> TP_ARGS(opcode, retval, retbuf), >> >> + TP_CONDITION(cpu_online(raw_smp_processor_id())), >> + >> TP_STRUCT__entry( >> __field(unsigned long, opcode) >> __field(unsigned long, retval) > >