This patch only provides the implementation of the method.
Later we will used it in a combination with a new option for
function tracing.
Signed-off-by: Yordan Karadzhov (VMware) <y.kar...@gmail.com>
---
kernel/trace/trace.c | 34 ++++++++++++++++++++++++++++++++++
kernel/trace/trace.h | 4 ++++
2 files changed, 38 insertions(+)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 82833be07c1e..66a4ad93b5e9 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3117,6 +3117,40 @@ static void ftrace_trace_userstack(struct trace_array
*tr,
#endif /* CONFIG_STACKTRACE */
+static inline void
+func_repeats_set_delta_ts(struct func_repeats_entry *entry,
+ unsigned long long delta)
+{
+ entry->bottom_delta_ts = delta & U32_MAX;
+ entry->top_delta_ts = (delta >> 32);
+}
+
+void trace_last_func_repeats(struct trace_array *tr,
+ struct trace_func_repeats *last_info,
+ unsigned int trace_ctx)
+{
+ struct trace_buffer *buffer = tr->array_buffer.buffer;
+ struct func_repeats_entry *entry;
+ struct ring_buffer_event *event;
+ u64 delta;
+
+ event = __trace_buffer_lock_reserve(buffer, TRACE_FUNC_REPEATS,
+ sizeof(*entry), trace_ctx);
+ if (!event)
+ return;
+
+ delta = ring_buffer_event_time_stamp(buffer, event) -
+ last_info->ts_last_call;
+
+ entry = ring_buffer_event_data(event);
+ entry->ip = last_info->ip;
+ entry->parent_ip = last_info->parent_ip;
+ entry->count = last_info->count;
+ func_repeats_set_delta_ts(entry, delta);
+
+ __buffer_unlock_commit(buffer, event);
+}
+
/* created for use with alloc_percpu */
struct trace_buffer_struct {
int nesting;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index a4f1b66049fd..cd80d046c7a5 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -695,6 +695,10 @@ static inline void __trace_stack(struct trace_array *tr,
unsigned int trace_ctx,
}
#endif /* CONFIG_STACKTRACE */
+void trace_last_func_repeats(struct trace_array *tr,
+ struct trace_func_repeats *last_info,
+ unsigned int trace_ctx);
+
extern u64 ftrace_now(int cpu);
extern void trace_find_cmdline(int pid, char comm[]);
--
2.25.1
