[RFC PATCH 1/6] jump_label: Add for_each_label_entry helper

[Daniel Bristot de Oliveira]

This patch adds the helper:
	for_each_label_entry(key, entry, stop)

For the "for each jump label entry" for defined as:
	for (; (entry < stop) && (jump_entry_key(entry) == key); entry++)

Simplifying the reading and usage.

Signed-off-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
Cc: Zhou Chengming <zhouchengming1@xxxxxxxxxx>
Cc: Jiri Kosina <jkosina@xxxxxxx>
Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: "Peter Zijlstra (Intel)" <peterz@xxxxxxxxxxxxx>
Cc: Chris von Recklinghausen <crecklin@xxxxxxxxxx>
Cc: Jason Baron <jbaron@xxxxxxxxxx>
Cc: Scott Wood <swood@xxxxxxxxxx>
Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
Cc: Clark Williams <williams@xxxxxxxxxx>
Cc: x86@xxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
 include/linux/jump_label.h | 3 +++
 kernel/jump_label.c        | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h
index 1a0b6f17a5d6..cd3bed880ca0 100644
--- a/include/linux/jump_label.h
+++ b/include/linux/jump_label.h
@@ -170,6 +170,9 @@ extern void static_key_disable(struct static_key *key);
 extern void static_key_enable_cpuslocked(struct static_key *key);
 extern void static_key_disable_cpuslocked(struct static_key *key);
 
+#define for_each_label_entry(key, entry, stop)				  \
+	for (; (entry < stop) && (jump_entry_key(entry) == key); entry++)
+
 /*
  * We should be using ATOMIC_INIT() for initializing .enabled, but
  * the inclusion of atomic.h is problematic for inclusion of jump_label.h
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index 2e62503bea0d..e853916a3b46 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -365,7 +365,7 @@ static void __jump_label_update(struct static_key *key,
 				struct jump_entry *entry,
 				struct jump_entry *stop)
 {
-	for (; (entry < stop) && (jump_entry_key(entry) == key); entry++) {
+	for_each_label_entry(key, entry, stop) {
 		/*
 		 * An entry->code of 0 indicates an entry which has been
 		 * disabled because it was in an init text area.
-- 
2.17.1