perf/ftrace: Optimize perf/tracepoint interaction for single events
When we've got but a single event per tracepoint
there is no reason to try and multiplex it so don't.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index c0f4b36..c809100 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -132,6 +132,7 @@
void *data;
int perf_refcount;
+ void *perf_data;
int (*perf_event_enable)(struct ftrace_event_call *);
void (*perf_event_disable)(struct ftrace_event_call *);
};
@@ -190,7 +191,7 @@
DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
-extern int perf_trace_enable(int event_id);
+extern int perf_trace_enable(int event_id, void *data);
extern void perf_trace_disable(int event_id);
extern int ftrace_profile_set_filter(struct perf_event *event, int event_id,
char *filter_str);
@@ -201,11 +202,12 @@
static inline void
perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
- u64 count, unsigned long irq_flags, struct pt_regs *regs)
+ u64 count, unsigned long irq_flags, struct pt_regs *regs,
+ void *event)
{
struct trace_entry *entry = raw_data;
- perf_tp_event(entry->type, addr, count, raw_data, size, regs);
+ perf_tp_event(entry->type, addr, count, raw_data, size, regs, event);
perf_swevent_put_recursion_context(rctx);
local_irq_restore(irq_flags);
}
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 3fd5c82..0b521fc 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -994,7 +994,7 @@
extern void perf_event_init(void);
extern void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
- int entry_size, struct pt_regs *regs);
+ int entry_size, struct pt_regs *regs, void *event);
extern void perf_bp_event(struct perf_event *event, void *data);
#ifndef perf_misc_flags
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 882c648..0a29df0 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -785,7 +785,8 @@
{ assign; } \
\
perf_trace_buf_submit(entry, __entry_size, rctx, __addr, \
- __count, irq_flags, __regs); \
+ __count, irq_flags, __regs, \
+ event_call->perf_data); \
}
#undef DEFINE_EVENT
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index a4fa381..17ac47f 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4468,8 +4468,9 @@
#ifdef CONFIG_EVENT_TRACING
void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
- int entry_size, struct pt_regs *regs)
+ int entry_size, struct pt_regs *regs, void *event)
{
+ const int type = PERF_TYPE_TRACEPOINT;
struct perf_sample_data data;
struct perf_raw_record raw = {
.size = entry_size,
@@ -4479,9 +4480,13 @@
perf_sample_data_init(&data, addr);
data.raw = &raw;
- /* Trace events already protected against recursion */
- do_perf_sw_event(PERF_TYPE_TRACEPOINT, event_id, count, 1,
- &data, regs);
+ if (!event) {
+ do_perf_sw_event(type, event_id, count, 1, &data, regs);
+ return;
+ }
+
+ if (perf_swevent_match(event, type, event_id, &data, regs))
+ perf_swevent_add(event, count, 1, &data, regs);
}
EXPORT_SYMBOL_GPL(perf_tp_event);
@@ -4514,7 +4519,7 @@
!capable(CAP_SYS_ADMIN))
return ERR_PTR(-EPERM);
- if (perf_trace_enable(event->attr.config))
+ if (perf_trace_enable(event->attr.config, event))
return NULL;
event->destroy = tp_perf_event_destroy;
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 0565bb4..89b780a 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -27,13 +27,15 @@
/* Count the events in use (per event id, not per instance) */
static int total_ref_count;
-static int perf_trace_event_enable(struct ftrace_event_call *event)
+static int perf_trace_event_enable(struct ftrace_event_call *event, void *data)
{
char *buf;
int ret = -ENOMEM;
- if (event->perf_refcount++ > 0)
+ if (event->perf_refcount++ > 0) {
+ event->perf_data = NULL;
return 0;
+ }
if (!total_ref_count) {
buf = (char *)alloc_percpu(perf_trace_t);
@@ -51,6 +53,7 @@
ret = event->perf_event_enable(event);
if (!ret) {
+ event->perf_data = data;
total_ref_count++;
return 0;
}
@@ -68,7 +71,7 @@
return ret;
}
-int perf_trace_enable(int event_id)
+int perf_trace_enable(int event_id, void *data)
{
struct ftrace_event_call *event;
int ret = -EINVAL;
@@ -77,7 +80,7 @@
list_for_each_entry(event, &ftrace_events, list) {
if (event->id == event_id && event->perf_event_enable &&
try_module_get(event->mod)) {
- ret = perf_trace_event_enable(event);
+ ret = perf_trace_event_enable(event, data);
break;
}
}
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index a751432..2d7bf41 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1362,7 +1362,7 @@
for (i = 0; i < tp->nr_args; i++)
call_fetch(&tp->args[i].fetch, regs, data + tp->args[i].offset);
- perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, irq_flags, regs);
+ perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, irq_flags, regs, call->perf_data);
}
/* Kretprobe profile handler */
@@ -1395,7 +1395,7 @@
call_fetch(&tp->args[i].fetch, regs, data + tp->args[i].offset);
perf_trace_buf_submit(entry, size, rctx, entry->ret_ip, 1,
- irq_flags, regs);
+ irq_flags, regs, call->perf_data);
}
static int probe_perf_enable(struct ftrace_event_call *call)
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 4d6d711..9eff1a4 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -468,7 +468,8 @@
rec->nr = syscall_nr;
syscall_get_arguments(current, regs, 0, sys_data->nb_args,
(unsigned long *)&rec->args);
- perf_trace_buf_submit(rec, size, rctx, 0, 1, flags, regs);
+ perf_trace_buf_submit(rec, size, rctx, 0, 1, flags, regs,
+ sys_data->enter_event->perf_data);
}
int perf_sysenter_enable(struct ftrace_event_call *call)
@@ -543,7 +544,8 @@
rec->nr = syscall_nr;
rec->ret = syscall_get_return_value(current, regs);
- perf_trace_buf_submit(rec, size, rctx, 0, 1, flags, regs);
+ perf_trace_buf_submit(rec, size, rctx, 0, 1, flags, regs,
+ sys_data->exit_event->perf_data);
}
int perf_sysexit_enable(struct ftrace_event_call *call)