[PATCH 3/6] perf_counter: powerpc: Change how processor-specific back-ends get selected

From: Paul Mackerras
Date: Wed Jun 17 2009 - 07:57:06 EST

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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@xxxxxxxxx>
---
arch/powerpc/include/asm/perf_counter.h | 5 ++-
arch/powerpc/kernel/perf_counter.c | 44 +++++--------------------------
arch/powerpc/kernel/power4-pmu.c | 15 ++++++++++-
arch/powerpc/kernel/power5+-pmu.c | 16 ++++++++++-
arch/powerpc/kernel/power5-pmu.c | 15 ++++++++++-
arch/powerpc/kernel/power6-pmu.c | 15 ++++++++++-
arch/powerpc/kernel/power7-pmu.c | 15 ++++++++++-
arch/powerpc/kernel/ppc970-pmu.c | 16 ++++++++++-
8 files changed, 96 insertions(+), 45 deletions(-)

diff --git a/arch/powerpc/include/asm/perf_counter.h b/arch/powerpc/include/asm/perf_counter.h
index 2ceb0fe..8ccd4e1 100644
--- a/arch/powerpc/include/asm/perf_counter.h
+++ b/arch/powerpc/include/asm/perf_counter.h
@@ -21,6 +21,7 @@
* describe the PMU on a particular POWER-family CPU.
*/
struct power_pmu {
+ const char *name;
int n_counter;
int max_alternatives;
unsigned long add_fields;
@@ -41,8 +42,6 @@ struct power_pmu {
[PERF_COUNT_HW_CACHE_RESULT_MAX];
};

-extern struct power_pmu *ppmu;
-
/*
* Values for power_pmu.flags
*/
@@ -56,6 +55,8 @@ extern struct power_pmu *ppmu;
#define PPMU_LIMITED_PMC_REQD 2 /* have to put this on a limited PMC */
#define PPMU_ONLY_COUNT_RUN 4 /* only counting in run state */

+extern int register_power_pmu(struct power_pmu *);
+
struct pt_regs;
extern unsigned long perf_misc_flags(struct pt_regs *regs);
extern unsigned long perf_instruction_pointer(struct pt_regs *regs);
diff --git a/arch/powerpc/kernel/perf_counter.c b/arch/powerpc/kernel/perf_counter.c
index 0249252..54e0489 100644
--- a/arch/powerpc/kernel/perf_counter.c
+++ b/arch/powerpc/kernel/perf_counter.c
@@ -1214,42 +1214,14 @@ void hw_perf_counter_setup(int cpu)
cpuhw->mmcr[0] = MMCR0_FC;
}

-extern struct power_pmu power4_pmu;
-extern struct power_pmu ppc970_pmu;
-extern struct power_pmu power5_pmu;
-extern struct power_pmu power5p_pmu;
-extern struct power_pmu power6_pmu;
-extern struct power_pmu power7_pmu;
-
-static int init_perf_counters(void)
+int register_power_pmu(struct power_pmu *pmu)
{
- unsigned long pvr;
-
- /* XXX should get this from cputable */
- pvr = mfspr(SPRN_PVR);
- switch (PVR_VER(pvr)) {
- case PV_POWER4:
- case PV_POWER4p:
- ppmu = &power4_pmu;
- break;
- case PV_970:
- case PV_970FX:
- case PV_970MP:
- ppmu = &ppc970_pmu;
- break;
- case PV_POWER5:
- ppmu = &power5_pmu;
- break;
- case PV_POWER5p:
- ppmu = &power5p_pmu;
- break;
- case 0x3e:
- ppmu = &power6_pmu;
- break;
- case 0x3f:
- ppmu = &power7_pmu;
- break;
- }
+ if (ppmu)
+ return -EBUSY; /* something's already registered */
+
+ ppmu = pmu;
+ pr_info("%s performance monitor hardware support registered\n",
+ pmu->name);

/*
* Use FCHV to ignore kernel events if MSR.HV is set.
@@ -1259,5 +1231,3 @@ static int init_perf_counters(void)

return 0;
}
-
-arch_initcall(init_perf_counters);
diff --git a/arch/powerpc/kernel/power4-pmu.c b/arch/powerpc/kernel/power4-pmu.c
index 81a1708..db90b0c 100644
--- a/arch/powerpc/kernel/power4-pmu.c
+++ b/arch/powerpc/kernel/power4-pmu.c
@@ -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 POWER4
@@ -587,7 +589,8 @@ static int power4_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
},
};

-struct power_pmu power4_pmu = {
+static struct power_pmu power4_pmu = {
+ .name = "POWER4/4+",
.n_counter = 8,
.max_alternatives = 5,
.add_fields = 0x0000001100005555ul,
@@ -600,3 +603,13 @@ struct power_pmu power4_pmu = {
.generic_events = p4_generic_events,
.cache_events = &power4_cache_events,
};
+
+static int init_power4_pmu(void)
+{
+ if (strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power4"))
+ return -ENODEV;
+
+ return register_power_pmu(&power4_pmu);
+}
+
+arch_initcall(init_power4_pmu);
diff --git a/arch/powerpc/kernel/power5+-pmu.c b/arch/powerpc/kernel/power5+-pmu.c
index aef144d..f4adca8 100644
--- a/arch/powerpc/kernel/power5+-pmu.c
+++ b/arch/powerpc/kernel/power5+-pmu.c
@@ -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 POWER5+ (POWER5 GS) and POWER5++ (POWER5 GS DD3)
@@ -657,7 +659,8 @@ static int power5p_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
},
};

-struct power_pmu power5p_pmu = {
+static struct power_pmu power5p_pmu = {
+ .name = "POWER5+/++",
.n_counter = 6,
.max_alternatives = MAX_ALT,
.add_fields = 0x7000000000055ul,
@@ -672,3 +675,14 @@ struct power_pmu power5p_pmu = {
.generic_events = power5p_generic_events,
.cache_events = &power5p_cache_events,
};
+
+static int init_power5p_pmu(void)
+{
+ if (strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power5+")
+ && strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power5++"))
+ return -ENODEV;
+
+ return register_power_pmu(&power5p_pmu);
+}
+
+arch_initcall(init_power5p_pmu);
diff --git a/arch/powerpc/kernel/power5-pmu.c b/arch/powerpc/kernel/power5-pmu.c
index 8694c73..29b2c6c 100644
--- a/arch/powerpc/kernel/power5-pmu.c
+++ b/arch/powerpc/kernel/power5-pmu.c
@@ -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 POWER5 (not POWER5++)
@@ -599,7 +601,8 @@ static int power5_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
},
};

-struct power_pmu power5_pmu = {
+static struct power_pmu power5_pmu = {
+ .name = "POWER5",
.n_counter = 6,
.max_alternatives = MAX_ALT,
.add_fields = 0x7000090000555ul,
@@ -612,3 +615,13 @@ struct power_pmu power5_pmu = {
.generic_events = power5_generic_events,
.cache_events = &power5_cache_events,
};
+
+static int init_power5_pmu(void)
+{
+ if (strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power5"))
+ return -ENODEV;
+
+ return register_power_pmu(&power5_pmu);
+}
+
+arch_initcall(init_power5_pmu);
diff --git a/arch/powerpc/kernel/power6-pmu.c b/arch/powerpc/kernel/power6-pmu.c
index 8898622..09ae5bf 100644
--- a/arch/powerpc/kernel/power6-pmu.c
+++ b/arch/powerpc/kernel/power6-pmu.c
@@ -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);
diff --git a/arch/powerpc/kernel/power7-pmu.c b/arch/powerpc/kernel/power7-pmu.c
index 658d1ae..5d755ef 100644
--- a/arch/powerpc/kernel/power7-pmu.c
+++ b/arch/powerpc/kernel/power7-pmu.c
@@ -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 POWER7
@@ -346,7 +348,8 @@ static int power7_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
},
};

-struct power_pmu power7_pmu = {
+static struct power_pmu power7_pmu = {
+ .name = "POWER7",
.n_counter = 6,
.max_alternatives = MAX_ALT + 1,
.add_fields = 0x1555ul,
@@ -359,3 +362,13 @@ struct power_pmu power7_pmu = {
.generic_events = power7_generic_events,
.cache_events = &power7_cache_events,
};
+
+static int init_power7_pmu(void)
+{
+ if (strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power7"))
+ return -ENODEV;
+
+ return register_power_pmu(&power7_pmu);
+}
+
+arch_initcall(init_power7_pmu);
diff --git a/arch/powerpc/kernel/ppc970-pmu.c b/arch/powerpc/kernel/ppc970-pmu.c
index 3ed8833..6637c87 100644
--- a/arch/powerpc/kernel/ppc970-pmu.c
+++ b/arch/powerpc/kernel/ppc970-pmu.c
@@ -10,7 +10,9 @@
*/
#include <linux/string.h>
#include <linux/perf_counter.h>
+#include <linux/string.h>
#include <asm/reg.h>
+#include <asm/cputable.h>

/*
* Bits in event code for PPC970
@@ -470,7 +472,8 @@ static int ppc970_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
},
};

-struct power_pmu ppc970_pmu = {
+static struct power_pmu ppc970_pmu = {
+ .name = "PPC970/FX/MP",
.n_counter = 8,
.max_alternatives = 2,
.add_fields = 0x001100005555ull,
@@ -483,3 +486,14 @@ struct power_pmu ppc970_pmu = {
.generic_events = ppc970_generic_events,
.cache_events = &ppc970_cache_events,
};
+
+static int init_ppc970_pmu(void)
+{
+ if (strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/970")
+ && strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/970MP"))
+ return -ENODEV;
+
+ return register_power_pmu(&ppc970_pmu);
+}
+
+arch_initcall(init_ppc970_pmu);
--
1.6.0.4

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Next message: Paul Mackerras: "[PATCH 4/6] perf_counter: powerpc: Make powerpc perf_counter code safe for 32-bit kernels"
Previous message: Paul Mackerras: "[PATCH 1/6] perf_counter: powerpc: Enable use of software counters on 32-bit powerpc"
In reply to: tip-bot for Paul Mackerras: "[tip:perfcounters/core] perf_counter: tools: Makefile tweaks for 64-bit powerpc"
Next in thread: tip-bot for Paul Mackerras: "[tip:perfcounters/powerpc] perf_counter: powerpc: Change how processor-specific back-ends get selected"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]