sched: latencytop support
LatencyTOP kernel infrastructure; it measures latencies in the
scheduler and tracks it system wide and per process.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c
index 6fa6cf0..55771fd 100644
--- a/arch/x86/kernel/stacktrace.c
+++ b/arch/x86/kernel/stacktrace.c
@@ -33,6 +33,19 @@
trace->entries[trace->nr_entries++] = addr;
}
+static void save_stack_address_nosched(void *data, unsigned long addr)
+{
+ struct stack_trace *trace = (struct stack_trace *)data;
+ if (in_sched_functions(addr))
+ return;
+ if (trace->skip > 0) {
+ trace->skip--;
+ return;
+ }
+ if (trace->nr_entries < trace->max_entries)
+ trace->entries[trace->nr_entries++] = addr;
+}
+
static const struct stacktrace_ops save_stack_ops = {
.warning = save_stack_warning,
.warning_symbol = save_stack_warning_symbol,
@@ -40,6 +53,13 @@
.address = save_stack_address,
};
+static const struct stacktrace_ops save_stack_ops_nosched = {
+ .warning = save_stack_warning,
+ .warning_symbol = save_stack_warning_symbol,
+ .stack = save_stack_stack,
+ .address = save_stack_address_nosched,
+};
+
/*
* Save stack-backtrace addresses into a stack_trace buffer.
*/
@@ -50,3 +70,10 @@
trace->entries[trace->nr_entries++] = ULONG_MAX;
}
EXPORT_SYMBOL(save_stack_trace);
+
+void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
+{
+ dump_trace(tsk, NULL, NULL, &save_stack_ops_nosched, trace);
+ if (trace->nr_entries < trace->max_entries)
+ trace->entries[trace->nr_entries++] = ULONG_MAX;
+}