locking/arch: Rename set_mb() to smp_store_mb()

Since set_mb() is really about an smp_mb() -- not a IO/DMA barrier
like mb() rename it to match the recent smp_load_acquire() and
smp_store_release().

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index f957461..fe4020e 100644 (file)
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -1662,7 +1662,7 @@ CPU from reordering them.
 
 There are some more advanced barrier functions:
 
- (*) set_mb(var, value)
+ (*) smp_store_mb(var, value)
 
      This assigns the value to the variable and then inserts a full memory
      barrier after it, depending on the function.  It isn't guaranteed to
@@ -1975,7 +1975,7 @@ after it has altered the task state:
        CPU 1
        ===============================
        set_current_state();
-         set_mb();
+         smp_store_mb();
            STORE current->state
            <general barrier>
        LOAD event_indicated
@@ -2016,7 +2016,7 @@ between the STORE to indicate the event and the STORE to set TASK_RUNNING:
        CPU 1                           CPU 2
        =============================== ===============================
        set_current_state();            STORE event_indicated
-         set_mb();                     wake_up();
+         smp_store_mb();               wake_up();
            STORE current->state          <write barrier>
            <general barrier>             STORE current->state
        LOAD event_indicated

diff --git a/arch/arm/include/asm/barrier.h b/arch/arm/include/asm/barrier.h
index 993150a..6c2327e 100644 (file)
--- a/arch/arm/include/asm/barrier.h
+++ b/arch/arm/include/asm/barrier.h
@@ -81,7 +81,7 @@ do {                                                                  \
 #define read_barrier_depends()         do { } while(0)
 #define smp_read_barrier_depends()     do { } while(0)
 
-#define set_mb(var, value)     do { WRITE_ONCE(var, value); smp_mb(); } while (0)
+#define smp_store_mb(var, value)       do { WRITE_ONCE(var, value); smp_mb(); } while (0)
 
 #define smp_mb__before_atomic()        smp_mb()
 #define smp_mb__after_atomic() smp_mb()

diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h
index ff7de78..0fa47c4 100644 (file)
--- a/arch/arm64/include/asm/barrier.h
+++ b/arch/arm64/include/asm/barrier.h
@@ -114,7 +114,7 @@ do {                                                                        \
 #define read_barrier_depends()         do { } while(0)
 #define smp_read_barrier_depends()     do { } while(0)
 
-#define set_mb(var, value)     do { WRITE_ONCE(var, value); smp_mb(); } while (0)
+#define smp_store_mb(var, value)       do { WRITE_ONCE(var, value); smp_mb(); } while (0)
 #define nop()          asm volatile("nop");
 
 #define smp_mb__before_atomic()        smp_mb()

diff --git a/arch/ia64/include/asm/barrier.h b/arch/ia64/include/asm/barrier.h
index 03117e7..843ba43 100644 (file)
--- a/arch/ia64/include/asm/barrier.h
+++ b/arch/ia64/include/asm/barrier.h
@@ -77,12 +77,7 @@ do {                                                                 \
        ___p1;                                                          \
 })
 
-/*
- * XXX check on this ---I suspect what Linus really wants here is
- * acquire vs release semantics but we can't discuss this stuff with
- * Linus just yet.  Grrr...
- */
-#define set_mb(var, value)     do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value)       do { WRITE_ONCE(var, value); mb(); } while (0)
 
 /*
  * The group barrier in front of the rsm & ssm are necessary to ensure

diff --git a/arch/metag/include/asm/barrier.h b/arch/metag/include/asm/barrier.h
index 97eb018..5a696e5 100644 (file)
--- a/arch/metag/include/asm/barrier.h
+++ b/arch/metag/include/asm/barrier.h
@@ -84,7 +84,7 @@ static inline void fence(void)
 #define read_barrier_depends()         do { } while (0)
 #define smp_read_barrier_depends()     do { } while (0)
 
-#define set_mb(var, value) do { WRITE_ONCE(var, value); smp_mb(); } while (0)
+#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); smp_mb(); } while (0)
 
 #define smp_store_release(p, v)                                                \
 do {                                                                   \

diff --git a/arch/mips/include/asm/barrier.h b/arch/mips/include/asm/barrier.h
index cff1bbd..7ecba84 100644 (file)
--- a/arch/mips/include/asm/barrier.h
+++ b/arch/mips/include/asm/barrier.h
@@ -112,7 +112,7 @@
 #define __WEAK_LLSC_MB         "               \n"
 #endif
 
-#define set_mb(var, value) \
+#define smp_store_mb(var, value) \
        do { WRITE_ONCE(var, value); smp_mb(); } while (0)
 
 #define smp_llsc_mb()  __asm__ __volatile__(__WEAK_LLSC_MB : : :"memory")

diff --git a/arch/powerpc/include/asm/barrier.h b/arch/powerpc/include/asm/barrier.h
index 2a072e4..39505d6 100644 (file)
--- a/arch/powerpc/include/asm/barrier.h
+++ b/arch/powerpc/include/asm/barrier.h
@@ -34,7 +34,7 @@
 #define rmb()  __asm__ __volatile__ ("sync" : : : "memory")
 #define wmb()  __asm__ __volatile__ ("sync" : : : "memory")
 
-#define set_mb(var, value)     do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value)       do { WRITE_ONCE(var, value); mb(); } while (0)
 
 #ifdef __SUBARCH_HAS_LWSYNC
 #    define SMPWMB      LWSYNC

diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h
index b66cd53..e6f8615 100644 (file)
--- a/arch/s390/include/asm/barrier.h
+++ b/arch/s390/include/asm/barrier.h
@@ -36,7 +36,7 @@
 #define smp_mb__before_atomic()                smp_mb()
 #define smp_mb__after_atomic()         smp_mb()
 
-#define set_mb(var, value)             do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value)               do { WRITE_ONCE(var, value); mb(); } while (0)
 
 #define smp_store_release(p, v)                                                \
 do {                                                                   \

diff --git a/arch/sh/include/asm/barrier.h b/arch/sh/include/asm/barrier.h
index 4371530..bf91037 100644 (file)
--- a/arch/sh/include/asm/barrier.h
+++ b/arch/sh/include/asm/barrier.h
@@ -32,7 +32,7 @@
 #define ctrl_barrier() __asm__ __volatile__ ("nop;nop;nop;nop;nop;nop;nop;nop")
 #endif
 
-#define set_mb(var, value) do { (void)xchg(&var, value); } while (0)
+#define smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0)
 
 #include <asm-generic/barrier.h>
 

diff --git a/arch/sparc/include/asm/barrier_64.h b/arch/sparc/include/asm/barrier_64.h
index 125fec7..809941e 100644 (file)
--- a/arch/sparc/include/asm/barrier_64.h
+++ b/arch/sparc/include/asm/barrier_64.h
@@ -40,7 +40,7 @@ do {  __asm__ __volatile__("ba,pt     %%xcc, 1f\n\t" \
 #define dma_rmb()      rmb()
 #define dma_wmb()      wmb()
 
-#define set_mb(__var, __value) \
+#define smp_store_mb(__var, __value) \
        do { WRITE_ONCE(__var, __value); membar_safe("#StoreLoad"); } while(0)
 
 #ifdef CONFIG_SMP

diff --git a/arch/x86/include/asm/barrier.h b/arch/x86/include/asm/barrier.h
index 9de5cde..e51a8f8 100644 (file)
--- a/arch/x86/include/asm/barrier.h
+++ b/arch/x86/include/asm/barrier.h
@@ -35,12 +35,12 @@
 #define smp_mb()       mb()
 #define smp_rmb()      dma_rmb()
 #define smp_wmb()      barrier()
-#define set_mb(var, value) do { (void)xchg(&var, value); } while (0)
+#define smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0)
 #else /* !SMP */
 #define smp_mb()       barrier()
 #define smp_rmb()      barrier()
 #define smp_wmb()      barrier()
-#define set_mb(var, value) do { WRITE_ONCE(var, value); barrier(); } while (0)
+#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); barrier(); } while (0)
 #endif /* SMP */
 
 #define read_barrier_depends()         do { } while (0)

diff --git a/arch/x86/um/asm/barrier.h b/arch/x86/um/asm/barrier.h
index cc0cb01..b9531d3 100644 (file)
--- a/arch/x86/um/asm/barrier.h
+++ b/arch/x86/um/asm/barrier.h
@@ -39,7 +39,8 @@
 #define smp_mb()       barrier()
 #define smp_rmb()      barrier()
 #define smp_wmb()      barrier()
-#define set_mb(var, value) do { WRITE_ONCE(var, value); barrier(); } while (0)
+
+#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); barrier(); } while (0)
 
 #define read_barrier_depends()         do { } while (0)
 #define smp_read_barrier_depends()     do { } while (0)

diff --git a/fs/select.c b/fs/select.c
index f684c75..0155473 100644 (file)
--- a/fs/select.c
+++ b/fs/select.c
@@ -189,7 +189,7 @@ static int __pollwake(wait_queue_t *wait, unsigned mode, int sync, void *key)
         * doesn't imply write barrier and the users expect write
         * barrier semantics on wakeup functions.  The following
         * smp_wmb() is equivalent to smp_wmb() in try_to_wake_up()
-        * and is paired with set_mb() in poll_schedule_timeout.
+        * and is paired with smp_store_mb() in poll_schedule_timeout.
         */
        smp_wmb();
        pwq->triggered = 1;
@@ -244,7 +244,7 @@ int poll_schedule_timeout(struct poll_wqueues *pwq, int state,
        /*
         * Prepare for the next iteration.
         *
-        * The following set_mb() serves two purposes.  First, it's
+        * The following smp_store_mb() serves two purposes.  First, it's
         * the counterpart rmb of the wmb in pollwake() such that data
         * written before wake up is always visible after wake up.
         * Second, the full barrier guarantees that triggered clearing
@@ -252,7 +252,7 @@ int poll_schedule_timeout(struct poll_wqueues *pwq, int state,
         * this problem doesn't exist for the first iteration as
         * add_wait_queue() has full barrier semantics.
         */
-       set_mb(pwq->triggered, 0);
+       smp_store_mb(pwq->triggered, 0);
 
        return rc;
 }

diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h
index 3938716..e6a83d7 100644 (file)
--- a/include/asm-generic/barrier.h
+++ b/include/asm-generic/barrier.h
@@ -66,8 +66,8 @@
 #define smp_read_barrier_depends()     do { } while (0)
 #endif
 
-#ifndef set_mb
-#define set_mb(var, value)  do { WRITE_ONCE(var, value); mb(); } while (0)
+#ifndef smp_store_mb
+#define smp_store_mb(var, value)  do { WRITE_ONCE(var, value); mb(); } while (0)
 #endif
 
 #ifndef smp_mb__before_atomic

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 26a2e61..18f1972 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -252,7 +252,7 @@ extern char ___assert_task_state[1 - 2*!!(
 #define set_task_state(tsk, state_value)                       \
        do {                                                    \
                (tsk)->task_state_change = _THIS_IP_;           \
-               set_mb((tsk)->state, (state_value));            \
+               smp_store_mb((tsk)->state, (state_value));              \
        } while (0)
 
 /*
@@ -274,7 +274,7 @@ extern char ___assert_task_state[1 - 2*!!(
 #define set_current_state(state_value)                         \
        do {                                                    \
                current->task_state_change = _THIS_IP_;         \
-               set_mb(current->state, (state_value));          \
+               smp_store_mb(current->state, (state_value));            \
        } while (0)
 
 #else
@@ -282,7 +282,7 @@ extern char ___assert_task_state[1 - 2*!!(
 #define __set_task_state(tsk, state_value)             \
        do { (tsk)->state = (state_value); } while (0)
 #define set_task_state(tsk, state_value)               \
-       set_mb((tsk)->state, (state_value))
+       smp_store_mb((tsk)->state, (state_value))
 
 /*
  * set_current_state() includes a barrier so that the write of current->state
@@ -298,7 +298,7 @@ extern char ___assert_task_state[1 - 2*!!(
 #define __set_current_state(state_value)               \
        do { current->state = (state_value); } while (0)
 #define set_current_state(state_value)                 \
-       set_mb(current->state, (state_value))
+       smp_store_mb(current->state, (state_value))
 
 #endif
 

diff --git a/kernel/futex.c b/kernel/futex.c
index 2579e40..55ca63a 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2055,7 +2055,7 @@ static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q,
 {
        /*
         * The task state is guaranteed to be set before another task can
-        * wake it. set_current_state() is implemented using set_mb() and
+        * wake it. set_current_state() is implemented using smp_store_mb() and
         * queue_me() calls spin_unlock() upon completion, both serializing
         * access to the hash list and forcing another memory barrier.
         */

diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h
index 27ab96d..04ab181 100644 (file)
--- a/kernel/locking/qspinlock_paravirt.h
+++ b/kernel/locking/qspinlock_paravirt.h
@@ -175,7 +175,7 @@ static void pv_wait_node(struct mcs_spinlock *node)
                 *
                 * Matches the xchg() from pv_kick_node().
                 */
-               set_mb(pn->state, vcpu_halted);
+               smp_store_mb(pn->state, vcpu_halted);
 
                if (!READ_ONCE(node->locked))
                        pv_wait(&pn->state, vcpu_halted);

diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c
index 852143a..9bc8232 100644 (file)
--- a/kernel/sched/wait.c
+++ b/kernel/sched/wait.c
@@ -341,7 +341,7 @@ long wait_woken(wait_queue_t *wait, unsigned mode, long timeout)
         * condition being true _OR_ WQ_FLAG_WOKEN such that we will not miss
         * an event.
         */
-       set_mb(wait->flags, wait->flags & ~WQ_FLAG_WOKEN); /* B */
+       smp_store_mb(wait->flags, wait->flags & ~WQ_FLAG_WOKEN); /* B */
 
        return timeout;
 }
@@ -354,7 +354,7 @@ int woken_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key)
         * doesn't imply write barrier and the users expects write
         * barrier semantics on wakeup functions.  The following
         * smp_wmb() is equivalent to smp_wmb() in try_to_wake_up()
-        * and is paired with set_mb() in wait_woken().
+        * and is paired with smp_store_mb() in wait_woken().
         */
        smp_wmb(); /* C */
        wait->flags |= WQ_FLAG_WOKEN;