From mboxrd@z Thu Jan 1 00:00:00 1970 From: mark.rutland@arm.com (Mark Rutland) Date: Thu, 27 Apr 2017 18:44:36 +0100 Subject: [PATCHv2 1/2] jump_label: Provide static_key_[enable|/slow_inc]_cpuslocked() In-Reply-To: <1493315077-19496-1-git-send-email-mark.rutland@arm.com> References: <1493315077-19496-1-git-send-email-mark.rutland@arm.com> Message-ID: <1493315077-19496-2-git-send-email-mark.rutland@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Sebastian Andrzej Siewior Provide static_key_[enable|slow_inc]_cpuslocked() variant that don't take cpu_hotplug_lock(). Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Mark Rutland Cc: Peter Zijlstra Cc: Sebastian Siewior Cc: Steven Rostedt Cc: jbaron at akamai.com --- include/linux/jump_label.h | 7 +++++++ kernel/jump_label.c | 10 ++++++++++ 2 files changed, 17 insertions(+) diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index d7b17d1..c80d8b1 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -164,6 +164,7 @@ extern void arch_jump_label_transform_static(struct jump_entry *entry, extern void jump_label_apply_nops(struct module *mod); extern int static_key_count(struct static_key *key); extern void static_key_enable(struct static_key *key); +extern void static_key_enable_cpuslocked(struct static_key *key); extern void static_key_disable(struct static_key *key); extern void static_key_disable_cpuslocked(struct static_key *key); @@ -252,6 +253,11 @@ static inline void static_key_enable(struct static_key *key) static_key_slow_inc(key); } +static inline void static_key_enable_cpuslocked(struct static_key *key) +{ + static_key_enable(key); +} + static inline void static_key_disable(struct static_key *key) { int count = static_key_count(key); @@ -429,6 +435,7 @@ struct static_key_false { */ #define static_branch_enable(x) static_key_enable(&(x)->key) +#define static_branch_enable_cpuslocked(x) static_key_enable_cpuslocked(&(x)->key) #define static_branch_disable(x) static_key_disable(&(x)->key) #define static_branch_disable_cpuslocked(x) static_key_disable_cpuslocked(&(x)->key) diff --git a/kernel/jump_label.c b/kernel/jump_label.c index d71124e..6343f4c 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -90,6 +90,16 @@ void static_key_enable(struct static_key *key) } EXPORT_SYMBOL_GPL(static_key_enable); +void static_key_enable_cpuslocked(struct static_key *key) +{ + int count = static_key_count(key); + + WARN_ON_ONCE(count < 0 || count > 1); + + if (!count) + static_key_slow_inc_cpuslocked(key); +} + void static_key_disable(struct static_key *key) { int count = static_key_count(key); -- 1.9.1