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From: Andy Lutomirski <luto@kernel.org>
To: x86@kernel.org, linux-kernel@vger.kernel.org
Cc: "Brian Gerst" <brgerst@gmail.com>,
	"Linus Torvalds" <torvalds@linux-foundation.org>,
	"Borislav Petkov" <bp@alien8.de>,
	"Frédéric Weisbecker" <fweisbec@gmail.com>,
	"Peter Zijlstra" <peterz@infradead.org>,
	"Andy Lutomirski" <luto@kernel.org>
Subject: [PATCH v3 2/5] context_tracking: Switch to new static_branch API
Date: Thu, 12 Nov 2015 12:59:01 -0800
Message-ID: <812df7e64f120c5c7c08481f36a8caa9f53b2199.1447361906.git.luto@kernel.org> (raw)
In-Reply-To: <cover.1447361906.git.luto@kernel.org>

This is much less error-prone than the old code.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
---
 include/linux/context_tracking_state.h | 4 ++--
 kernel/context_tracking.c              | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/linux/context_tracking_state.h b/include/linux/context_tracking_state.h
index ee956c528fab..1d34fe68f48a 100644
--- a/include/linux/context_tracking_state.h
+++ b/include/linux/context_tracking_state.h
@@ -22,12 +22,12 @@ struct context_tracking {
 };
 
 #ifdef CONFIG_CONTEXT_TRACKING
-extern struct static_key context_tracking_enabled;
+extern struct static_key_false context_tracking_enabled;
 DECLARE_PER_CPU(struct context_tracking, context_tracking);
 
 static inline bool context_tracking_is_enabled(void)
 {
-	return static_key_false(&context_tracking_enabled);
+	return static_branch_unlikely(&context_tracking_enabled);
 }
 
 static inline bool context_tracking_cpu_is_enabled(void)
diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index 0a495ab35bc7..d0fb09e40784 100644
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -24,7 +24,7 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/context_tracking.h>
 
-struct static_key context_tracking_enabled = STATIC_KEY_INIT_FALSE;
+DEFINE_STATIC_KEY_FALSE(context_tracking_enabled);
 EXPORT_SYMBOL_GPL(context_tracking_enabled);
 
 DEFINE_PER_CPU(struct context_tracking, context_tracking);
@@ -191,7 +191,7 @@ void __init context_tracking_cpu_set(int cpu)
 
 	if (!per_cpu(context_tracking.active, cpu)) {
 		per_cpu(context_tracking.active, cpu) = true;
-		static_key_slow_inc(&context_tracking_enabled);
+		static_branch_inc(&context_tracking_enabled);
 	}
 
 	if (initialized)
-- 
2.5.0


  parent reply index

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-12 20:58 [PATCH v3 0/5] x86 entry stuff, maybe for 4.4 Andy Lutomirski
2015-11-12 20:59 ` [PATCH v3 1/5] x86/entry/64: Fix irqflag tracing wrt context tracking Andy Lutomirski
2015-11-24  9:35   ` [tip:x86/asm] " tip-bot for Andy Lutomirski
2015-11-12 20:59 ` Andy Lutomirski [this message]
2015-11-24  9:35   ` [tip:x86/asm] context_tracking: Switch to new static_branch API tip-bot for Andy Lutomirski
2015-11-12 20:59 ` [PATCH v3 3/5] x86/asm: Error out if asm/jump_label.h is included inappropriately Andy Lutomirski
2015-11-13 14:13   ` Thomas Gleixner
2015-11-24  9:35   ` [tip:x86/asm] x86/asm: Error out if asm/ jump_label.h " tip-bot for Andy Lutomirski
2015-11-12 20:59 ` [PATCH v3 4/5] x86/asm: Add asm macros for static keys/jump labels Andy Lutomirski
2015-11-13 14:22   ` Thomas Gleixner
2015-11-24  9:36   ` [tip:x86/asm] " tip-bot for Andy Lutomirski
2015-11-12 20:59 ` [PATCH v3 5/5] x86/entry/64: Bypass enter_from_user_mode on non-context-tracking boots Andy Lutomirski
2015-11-13 14:23   ` Thomas Gleixner
2015-11-13 15:26   ` Frederic Weisbecker
2015-11-16 19:10     ` Andy Lutomirski
2015-11-16 22:50       ` Frederic Weisbecker
2015-11-16 23:57         ` Andy Lutomirski
2015-11-19  0:57           ` Frederic Weisbecker
2015-11-24  9:36   ` [tip:x86/asm] " tip-bot for Andy Lutomirski

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