[PATCH v2 bpf-next 1/4] perf: export get/put_chain_entry()

[Song Liu]

This would be used by bpf stack mapo.

Signed-off-by: Song Liu <songliubrav...@fb.com>
---
 include/linux/perf_event.h | 2 ++
 kernel/events/callchain.c  | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index b4bb32082342c..00ab5efa38334 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1244,6 +1244,8 @@ get_perf_callchain(struct pt_regs *regs, u32 init_nr, 
bool kernel, bool user,
 extern struct perf_callchain_entry *perf_callchain(struct perf_event *event, 
struct pt_regs *regs);
 extern int get_callchain_buffers(int max_stack);
 extern void put_callchain_buffers(void);
+extern struct perf_callchain_entry *get_callchain_entry(int *rctx);
+extern void put_callchain_entry(int rctx);
 
 extern int sysctl_perf_event_max_stack;
 extern int sysctl_perf_event_max_contexts_per_stack;
diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c
index 334d48b16c36d..50b8a1622807f 100644
--- a/kernel/events/callchain.c
+++ b/kernel/events/callchain.c
@@ -149,7 +149,7 @@ void put_callchain_buffers(void)
        }
 }
 
-static struct perf_callchain_entry *get_callchain_entry(int *rctx)
+struct perf_callchain_entry *get_callchain_entry(int *rctx)
 {
        int cpu;
        struct callchain_cpus_entries *entries;
@@ -168,7 +168,7 @@ static struct perf_callchain_entry *get_callchain_entry(int 
*rctx)
                (*rctx * perf_callchain_entry__sizeof()));
 }
 
-static void
+void
 put_callchain_entry(int rctx)
 {
        put_recursion_context(this_cpu_ptr(callchain_recursion), rctx);
-- 
2.24.1