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Diffstat (limited to 'kernel/trace/trace_event_perf.c')
-rw-r--r--kernel/trace/trace_event_perf.c34
1 files changed, 15 insertions, 19 deletions
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index cb6f365016e..000e6e85b44 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -9,8 +9,6 @@
#include <linux/kprobes.h>
#include "trace.h"
-EXPORT_SYMBOL_GPL(perf_arch_fetch_caller_regs);
-
static char *perf_trace_buf[4];
/*
@@ -56,13 +54,7 @@ static int perf_trace_event_init(struct ftrace_event_call *tp_event,
}
}
- if (tp_event->class->reg)
- ret = tp_event->class->reg(tp_event, TRACE_REG_PERF_REGISTER);
- else
- ret = tracepoint_probe_register(tp_event->name,
- tp_event->class->perf_probe,
- tp_event);
-
+ ret = tp_event->class->reg(tp_event, TRACE_REG_PERF_REGISTER);
if (ret)
goto fail;
@@ -96,7 +88,7 @@ int perf_trace_init(struct perf_event *p_event)
mutex_lock(&event_mutex);
list_for_each_entry(tp_event, &ftrace_events, list) {
if (tp_event->event.type == event_id &&
- tp_event->class && tp_event->class->perf_probe &&
+ tp_event->class && tp_event->class->reg &&
try_module_get(tp_event->mod)) {
ret = perf_trace_event_init(tp_event, p_event);
break;
@@ -116,7 +108,7 @@ int perf_trace_enable(struct perf_event *p_event)
if (WARN_ON_ONCE(!list))
return -EINVAL;
- list = per_cpu_ptr(list, smp_processor_id());
+ list = this_cpu_ptr(list);
hlist_add_head_rcu(&p_event->hlist_entry, list);
return 0;
@@ -132,15 +124,17 @@ void perf_trace_destroy(struct perf_event *p_event)
struct ftrace_event_call *tp_event = p_event->tp_event;
int i;
+ mutex_lock(&event_mutex);
if (--tp_event->perf_refcount > 0)
- return;
+ goto out;
- if (tp_event->class->reg)
- tp_event->class->reg(tp_event, TRACE_REG_PERF_UNREGISTER);
- else
- tracepoint_probe_unregister(tp_event->name,
- tp_event->class->perf_probe,
- tp_event);
+ tp_event->class->reg(tp_event, TRACE_REG_PERF_UNREGISTER);
+
+ /*
+ * Ensure our callback won't be called anymore. The buffers
+ * will be freed after that.
+ */
+ tracepoint_synchronize_unregister();
free_percpu(tp_event->perf_events);
tp_event->perf_events = NULL;
@@ -151,6 +145,8 @@ void perf_trace_destroy(struct perf_event *p_event)
perf_trace_buf[i] = NULL;
}
}
+out:
+ mutex_unlock(&event_mutex);
}
__kprobes void *perf_trace_buf_prepare(int size, unsigned short type,
@@ -169,7 +165,7 @@ __kprobes void *perf_trace_buf_prepare(int size, unsigned short type,
if (*rctxp < 0)
return NULL;
- raw_data = per_cpu_ptr(perf_trace_buf[*rctxp], smp_processor_id());
+ raw_data = this_cpu_ptr(perf_trace_buf[*rctxp]);
/* zero the dead bytes from align to not leak stack to user */
memset(&raw_data[size - sizeof(u64)], 0, sizeof(u64));