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perf_counter: powerpc: Change how processor-specific back-ends get selected

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At present, the powerpc generic (processor-independent) perf_counter
code has list of processor back-end modules, and at initialization,
it looks at the PVR (processor version register) and has a switch
statement to select a suitable processor-specific back-end.

This is going to become inconvenient as we add more processor-specific
back-ends, so this inverts the order: now each back-end checks whether
it applies to the current processor, and registers itself if so.
Furthermore, instead of looking at the PVR, back-ends now check the
cur_cpu_spec->oprofile_cpu_type string and match on that.

Lastly, each back-end now specifies a name for itself so the core can
print a nice message when a back-end registers itself.

This doesn't provide any support for unregistering back-ends, but that
wouldn't be hard to do and would allow back-ends to be modules.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linuxppc-dev@ozlabs.org
Cc: benh@kernel.crashing.org
LKML-Reference: <19000.55529.762227.518531@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Paul Mackerras
2009-06-17 21:52:09 +10:00
committed by Ingo Molnar
parent 448d64f8f4
commit 079b3c569c
8 changed files with 95 additions and 44 deletions
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15
arch/powerpc/kernel/power6-pmu.c
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@ -10,7 +10,9 @@
*/
#include <linux/kernel.h>
#include <linux/perf_counter.h>
#include <linux/string.h>
#include <asm/reg.h>
#include <asm/cputable.h>
/*
* Bits in event code for POWER6
@ -516,7 +518,8 @@ static int power6_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
},
};
struct power_pmu power6_pmu = {
static struct power_pmu power6_pmu = {
.name = "POWER6",
.n_counter = 6,
.max_alternatives = MAX_ALT,
.add_fields = 0x1555,
@ -531,3 +534,13 @@ struct power_pmu power6_pmu = {
.generic_events = power6_generic_events,
.cache_events = &power6_cache_events,
};
static int init_power6_pmu(void)
{
if (strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power6"))
return -ENODEV;
return register_power_pmu(&power6_pmu);
}
arch_initcall(init_power6_pmu);