[PATCH 1/5] ftrace: Make ftrace_location_range() global
From: Michael Ellerman
Date: Wed Apr 13 2016 - 08:53:50 EST
In order to support live patching on powerpc we would like to call
ftrace_location_range(), so make it global.
Signed-off-by: Torsten Duwe <duwe@xxxxxxx>
Signed-off-by: Balbir Singh <bsingharora@xxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
---
include/linux/ftrace.h | 1 +
kernel/trace/ftrace.c | 14 +++++++++++++-
2 files changed, 14 insertions(+), 1 deletion(-)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index dea12a6e413b..66a36a815f0a 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -455,6 +455,7 @@ int ftrace_update_record(struct dyn_ftrace *rec, int enable);
int ftrace_test_record(struct dyn_ftrace *rec, int enable);
void ftrace_run_stop_machine(int command);
unsigned long ftrace_location(unsigned long ip);
+unsigned long ftrace_location_range(unsigned long start, unsigned long end);
unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec);
unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec);
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index b1870fbd2b67..7e8d792da963 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1530,7 +1530,19 @@ static int ftrace_cmp_recs(const void *a, const void *b)
return 0;
}
-static unsigned long ftrace_location_range(unsigned long start, unsigned long end)
+/**
+ * ftrace_location_range - return the first address of a traced location
+ * if it touches the given ip range
+ * @start: start of range to search.
+ * @end: end of range to search (inclusive). @end points to the last byte
+ * to check.
+ *
+ * Returns rec->ip if the related ftrace location is a least partly within
+ * the given address range. That is, the first address of the instruction
+ * that is either a NOP or call to the function tracer. It checks the ftrace
+ * internal tables to determine if the address belongs or not.
+ */
+unsigned long ftrace_location_range(unsigned long start, unsigned long end)
{
struct ftrace_page *pg;
struct dyn_ftrace *rec;
--
2.5.0