[RFC][PATCH 6/8] perf: Dynamic pmu types

From: Peter Zijlstra
Date: Wed Nov 17 2010 - 17:23:16 EST

Next message: Peter Zijlstra: "[RFC][PATCH 8/8] perf: Sysfs events"
Previous message: Greg KH: "Re: How do I choose an arbitrary minor number for my tty device?"
In reply to: Peter Zijlstra: "[RFC][PATCH 0/8] perf sysfs bits"
Next in thread: Peter Zijlstra: "[RFC][PATCH 8/8] perf: Sysfs events"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

Extend the perf_pmu_register() interface to allow for named and
dynamic pmu types.

Because we need to support the existing static types we cannot use
dynamic types for everything, hence provide a type argument.

If we want to enumerate the PMUs they need a name, provide one.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
---
arch/alpha/kernel/perf_event.c | 2 -
arch/arm/kernel/perf_event.c | 2 -
arch/powerpc/kernel/perf_event.c | 2 -
arch/powerpc/kernel/perf_event_fsl_emb.c | 2 -
arch/sh/kernel/perf_event.c | 2 -
arch/sparc/kernel/perf_event.c | 2 -
arch/x86/kernel/cpu/perf_event.c | 2 -
include/linux/perf_event.h | 5 ++-
kernel/hw_breakpoint.c | 2 -
kernel/perf_event.c | 49 +++++++++++++++++++++++++++----
10 files changed, 55 insertions(+), 15 deletions(-)

Index: linux-2.6/include/linux/perf_event.h
===================================================================
--- linux-2.6.orig/include/linux/perf_event.h
+++ linux-2.6/include/linux/perf_event.h
@@ -578,6 +578,9 @@ struct perf_event;
struct pmu {
struct list_head entry;

+ char *name;
+ int type;
+
int * __percpu pmu_disable_count;
struct perf_cpu_context * __percpu pmu_cpu_context;
int task_ctx_nr;
@@ -901,7 +904,7 @@ struct perf_output_handle {

#ifdef CONFIG_PERF_EVENTS

-extern int perf_pmu_register(struct pmu *pmu);
+extern int perf_pmu_register(struct pmu *pmu, char *name, int type);
extern void perf_pmu_unregister(struct pmu *pmu);

extern int perf_num_counters(void);
Index: linux-2.6/kernel/perf_event.c
===================================================================
--- linux-2.6.orig/kernel/perf_event.c
+++ linux-2.6/kernel/perf_event.c
@@ -13,6 +13,7 @@
#include <linux/mm.h>
#include <linux/cpu.h>
#include <linux/smp.h>
+#include <linux/idr.h>
#include <linux/file.h>
#include <linux/poll.h>
#include <linux/slab.h>
@@ -4804,7 +4805,7 @@ static struct pmu perf_tracepoint = {

static __init int perf_tp_init(void)
{
- perf_pmu_register(&perf_tracepoint);
+ perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT);
return 0;
}
early_initcall(perf_tp_init);
@@ -5111,6 +5112,8 @@ static void *find_pmu_context(int ctxn)
return NULL;
}

+static struct idr pmu_idr;
+
static void free_pmu_context(void * __percpu cpu_context)
{
struct pmu *pmu;
@@ -5129,7 +5132,7 @@ static void free_pmu_context(void * __pe
mutex_unlock(&pmus_lock);
}

-int perf_pmu_register(struct pmu *pmu)
+int perf_pmu_register(struct pmu *pmu, char *name, int type)
{
int cpu, ret;

@@ -5139,13 +5142,32 @@ int perf_pmu_register(struct pmu *pmu)
if (!pmu->pmu_disable_count)
goto unlock;

+ pmu->type = -1;
+ if (!name)
+ goto skip_type;
+ pmu->name = name;
+
+ if (type < 0) {
+ int err = idr_pre_get(&pmu_idr, GFP_KERNEL);
+ if (!err)
+ goto free_pdc;
+
+ err = idr_get_new_above(&pmu_idr, pmu, PERF_TYPE_MAX, &type);
+ if (err) {
+ ret = err;
+ goto free_pdc;
+ }
+ }
+ pmu->type = type;
+
+skip_type:
pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr);
if (pmu->pmu_cpu_context)
goto got_cpu_context;

pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context);
if (!pmu->pmu_cpu_context)
- goto free_pdc;
+ goto free_ird;

for_each_possible_cpu(cpu) {
struct perf_cpu_context *cpuctx;
@@ -5188,6 +5210,10 @@ int perf_pmu_register(struct pmu *pmu)

return ret;

+free_idr:
+ if (pmu->type >= PERF_TYPE_MAX)
+ idr_remove(&pmu_idr, pmu->type);
+
free_pdc:
free_percpu(pmu->pmu_disable_count);
goto unlock;
@@ -5207,6 +5233,8 @@ void perf_pmu_unregister(struct pmu *pmu
synchronize_rcu();

free_percpu(pmu->pmu_disable_count);
+ if (pmu->type >= PERF_TYPE_MAX)
+ idr_remove(&pmu_idr, pmu->type);
free_pmu_context(pmu->pmu_cpu_context);
}

@@ -5216,6 +5244,13 @@ struct pmu *perf_init_event(struct perf_
int idx;

idx = srcu_read_lock(&pmus_srcu);
+
+ rcu_read_lock();
+ pmu = idr_find(&pmu_idr, event->attr.type);
+ rcu_read_unlock();
+ if (pmu)
+ goto unlock;
+
list_for_each_entry_rcu(pmu, &pmus, entry) {
int ret = pmu->event_init(event);
if (!ret)
@@ -6319,10 +6354,12 @@ perf_cpu_notify(struct notifier_block *s

void __init perf_event_init(void)
{
+ idr_init(&pmu_idr);
+
perf_event_init_all_cpus();
init_srcu_struct(&pmus_srcu);
- perf_pmu_register(&perf_swevent);
- perf_pmu_register(&perf_cpu_clock);
- perf_pmu_register(&perf_task_clock);
+ perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE);
+ perf_pmu_register(&perf_cpu_clock, NULL, -1);
+ perf_pmu_register(&perf_task_clock, NULL, -1);
perf_cpu_notifier(perf_cpu_notify);
}
Index: linux-2.6/arch/alpha/kernel/perf_event.c
===================================================================
--- linux-2.6.orig/arch/alpha/kernel/perf_event.c
+++ linux-2.6/arch/alpha/kernel/perf_event.c
@@ -882,7 +882,7 @@ int __init init_hw_perf_events(void)
/* And set up PMU specification */
alpha_pmu = &ev67_pmu;

- perf_pmu_register(&pmu);
+ perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW);

return 0;
}
Index: linux-2.6/arch/arm/kernel/perf_event.c
===================================================================
--- linux-2.6.orig/arch/arm/kernel/perf_event.c
+++ linux-2.6/arch/arm/kernel/perf_event.c
@@ -3034,7 +3034,7 @@ init_hw_perf_events(void)
pr_info("no hardware support available\n");
}

- perf_pmu_register(&pmu);
+ perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW);

return 0;
}
Index: linux-2.6/arch/powerpc/kernel/perf_event.c
===================================================================
--- linux-2.6.orig/arch/powerpc/kernel/perf_event.c
+++ linux-2.6/arch/powerpc/kernel/perf_event.c
@@ -1379,7 +1379,7 @@ int register_power_pmu(struct power_pmu
freeze_events_kernel = MMCR0_FCHV;
#endif /* CONFIG_PPC64 */

- perf_pmu_register(&power_pmu);
+ perf_pmu_register(&power_pmu, "cpu", PERF_TYPE_RAW);
perf_cpu_notifier(power_pmu_notifier);

return 0;
Index: linux-2.6/arch/powerpc/kernel/perf_event_fsl_emb.c
===================================================================
--- linux-2.6.orig/arch/powerpc/kernel/perf_event_fsl_emb.c
+++ linux-2.6/arch/powerpc/kernel/perf_event_fsl_emb.c
@@ -681,7 +681,7 @@ int register_fsl_emb_pmu(struct fsl_emb_
pr_info("%s performance monitor hardware support registered\n",
pmu->name);

- perf_pmu_register(&fsl_emb_pmu);
+ perf_pmu_register(&fsl_emb_pmu, "cpu", PERF_TYPE_RAW);

return 0;
}
Index: linux-2.6/arch/sh/kernel/perf_event.c
===================================================================
--- linux-2.6.orig/arch/sh/kernel/perf_event.c
+++ linux-2.6/arch/sh/kernel/perf_event.c
@@ -389,7 +389,7 @@ int __cpuinit register_sh_pmu(struct sh_

WARN_ON(_pmu->num_events > MAX_HWEVENTS);

- perf_pmu_register(&pmu);
+ perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW);
perf_cpu_notifier(sh_pmu_notifier);
return 0;
}
Index: linux-2.6/arch/sparc/kernel/perf_event.c
===================================================================
--- linux-2.6.orig/arch/sparc/kernel/perf_event.c
+++ linux-2.6/arch/sparc/kernel/perf_event.c
@@ -1318,7 +1318,7 @@ int __init init_hw_perf_events(void)

pr_cont("Supported PMU type is '%s'\n", sparc_pmu_type);

- perf_pmu_register(&pmu);
+ perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW);
register_die_notifier(&perf_event_nmi_notifier);

return 0;
Index: linux-2.6/arch/x86/kernel/cpu/perf_event.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/cpu/perf_event.c
+++ linux-2.6/arch/x86/kernel/cpu/perf_event.c
@@ -1418,7 +1418,7 @@ int __init init_hw_perf_events(void)
pr_info("... fixed-purpose events: %d\n", x86_pmu.num_counters_fixed);
pr_info("... event mask: %016Lx\n", x86_pmu.intel_ctrl);

- perf_pmu_register(&pmu);
+ perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW);
perf_cpu_notifier(x86_pmu_notifier);

return 0;
Index: linux-2.6/kernel/hw_breakpoint.c
===================================================================
--- linux-2.6.orig/kernel/hw_breakpoint.c
+++ linux-2.6/kernel/hw_breakpoint.c
@@ -641,7 +641,7 @@ static int __init init_hw_breakpoint(voi

constraints_initialized = 1;

- perf_pmu_register(&perf_breakpoint);
+ perf_pmu_register(&perf_breakpoint, "breakpoint", PERF_TYPE_BREAKPOINT);

return register_die_notifier(&hw_breakpoint_exceptions_nb);

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

Next message: Peter Zijlstra: "[RFC][PATCH 8/8] perf: Sysfs events"
Previous message: Greg KH: "Re: How do I choose an arbitrary minor number for my tty device?"
In reply to: Peter Zijlstra: "[RFC][PATCH 0/8] perf sysfs bits"
Next in thread: Peter Zijlstra: "[RFC][PATCH 8/8] perf: Sysfs events"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]