[PATCH bpf-next] bpf: Make symbol 'bpf_task_storage_busy' static

["'Wei Yongjun" <weiyongjun1@xxxxxxxxxx>]

From: Wei Yongjun <weiyongjun1@xxxxxxxxxx>

The sparse tool complains as follows:

kernel/bpf/bpf_task_storage.c:23:1: warning:
 symbol '__pcpu_scope_bpf_task_storage_busy' was not declared. Should it be static?

This symbol is not used outside of bpf_task_storage.c, so this
commit marks it static.

Fixes: bc235cdb423a ("bpf: Prevent deadlock from recursive bpf_task_storage_[get|delete]")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Wei Yongjun <weiyongjun1@xxxxxxxxxx>
---
 kernel/bpf/bpf_task_storage.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/bpf/bpf_task_storage.c b/kernel/bpf/bpf_task_storage.c
index fd3c74ef608e..3ce75758d394 100644
--- a/kernel/bpf/bpf_task_storage.c
+++ b/kernel/bpf/bpf_task_storage.c
@@ -20,7 +20,7 @@
 
 DEFINE_BPF_STORAGE_CACHE(task_cache);
 
-DEFINE_PER_CPU(int, bpf_task_storage_busy);
+static DEFINE_PER_CPU(int, bpf_task_storage_busy);
 
 static void bpf_task_storage_lock(void)
 {