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parisc: Fix automatic selection of cr16 clocksource

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Commit 54b6680090 (parisc: Add native high-resolution sched_clock()
implementation) added support to use the CPU-internal cr16 counters as reliable
clocksource with the help of HAVE_UNSTABLE_SCHED_CLOCK.

Sadly the commit missed to remove the hack which prevented cr16 to become the
default clocksource even on SMP systems.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 4.7+
This commit is contained in:
Helge Deller
2016-08-19 22:39:02 +02:00
parent 6040e57658
commit ae141830b1
2 changed files with 0 additions and 20 deletions
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8
arch/parisc/kernel/processor.c
View File

@ -51,8 +51,6 @@ EXPORT_SYMBOL(_parisc_requires_coherency);
DEFINE_PER_CPU(struct cpuinfo_parisc, cpu_data); DEFINE_PER_CPU(struct cpuinfo_parisc, cpu_data);
extern int update_cr16_clocksource(void); /* from time.c */
/* /*
** PARISC CPU driver - claim "device" and initialize CPU data structures. ** PARISC CPU driver - claim "device" and initialize CPU data structures.
** **
@ -228,12 +226,6 @@ static int processor_probe(struct parisc_device *dev)
} }
#endif #endif
/* If we've registered more than one cpu,
* we'll use the jiffies clocksource since cr16
* is not synchronized between CPUs.
*/
update_cr16_clocksource();
return 0; return 0;
} }

12
arch/parisc/kernel/time.c
View File

@ -221,18 +221,6 @@ static struct clocksource clocksource_cr16 = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS, .flags = CLOCK_SOURCE_IS_CONTINUOUS,
}; };
int update_cr16_clocksource(void)
{
/* since the cr16 cycle counters are not synchronized across CPUs,
we'll check if we should switch to a safe clocksource: */
if (clocksource_cr16.rating != 0 && num_online_cpus() > 1) {
clocksource_change_rating(&clocksource_cr16, 0);
return 1;
}
return 0;
}
void __init start_cpu_itimer(void) void __init start_cpu_itimer(void)
{ {
unsigned int cpu = smp_processor_id(); unsigned int cpu = smp_processor_id();