kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

x86, perf events: Check if we have APIC enabled

Browse source 
Ralf Hildebrandt reported this boot warning:

| Running a vanilla 2.6.32 as Xen DomU, I'm getting:
|
| [    0.000999] CPU: Physical Processor ID: 0
| [    0.000999] CPU: Processor Core ID: 1
| [    0.000999] Performance Events: AMD PMU driver.
| [    0.000999] ------------[ cut here ]------------
| [    0.000999] WARNING: at arch/x86/kernel/apic/apic.c:249 native_apic_write_dummy

So we need to check if APIC functionality is available, and
not just in the P6 driver but elsewhere as well.

Reported-by: Ralf Hildebrandt <Ralf.Hildebrandt@charite.de>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091210165634.GF5086@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Cyrill Gorcunov 2009-12-10 19:56:34 +03:00 committed by Ingo Molnar
parent 5e855db5d8
commit 125580380f
1 changed files with 12 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

18
arch/x86/kernel/cpu/perf_event.c
View file

@ -2066,12 +2066,6 @@ static __init int p6_pmu_init(void)
x86_pmu = p6_pmu; x86_pmu = p6_pmu;
if (!cpu_has_apic) {
pr_info("no APIC, boot with the \"lapic\" boot parameter to force-enable it.\n");
pr_info("no hardware sampling interrupt available.\n");
x86_pmu.apic = 0;
}
return 0; return 0;
} }
@ -2163,6 +2157,16 @@ static __init int amd_pmu_init(void)
return 0; return 0;
} }
static void __init pmu_check_apic(void)
{
if (cpu_has_apic)
return;
x86_pmu.apic = 0;
pr_info("no APIC, boot with the \"lapic\" boot parameter to force-enable it.\n");
pr_info("no hardware sampling interrupt available.\n");
}
void __init init_hw_perf_events(void) void __init init_hw_perf_events(void)
{ {
int err; int err;
@ -2184,6 +2188,8 @@ void __init init_hw_perf_events(void)
return; return;
} }
pmu_check_apic();
pr_cont("%s PMU driver.\n", x86_pmu.name); pr_cont("%s PMU driver.\n", x86_pmu.name);
if (x86_pmu.num_events > X86_PMC_MAX_GENERIC) { if (x86_pmu.num_events > X86_PMC_MAX_GENERIC) {