lkml.org 
[lkml]   [2015]   [Jul]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3.16.y-ckt 109/185] locking,arch,arc: Fold atomic_ops
Date
3.16.7-ckt15 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Peter Zijlstra <peterz@infradead.org>

commit f7d11e93ee97a37da1947b7c4e1794705a6f360c upstream.

Many of the atomic op implementations are the same except for one
instruction; fold the lot into a few CPP macros and reduce LoC.

This also prepares for easy addition of new ops.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Link: http://lkml.kernel.org/r/20140508135851.886055622@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[ luis: 3.16 prereq for:
2576c28e3f62 "ARC: add smp barriers around atomics per Documentation/atomic_ops.txt"
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
arch/arc/include/asm/atomic.h | 184 +++++++++++++++---------------------------
1 file changed, 63 insertions(+), 121 deletions(-)

diff --git a/arch/arc/include/asm/atomic.h b/arch/arc/include/asm/atomic.h
index 83f03ca6caf6..173f303a868f 100644
--- a/arch/arc/include/asm/atomic.h
+++ b/arch/arc/include/asm/atomic.h
@@ -25,79 +25,36 @@

#define atomic_set(v, i) (((v)->counter) = (i))

-static inline void atomic_add(int i, atomic_t *v)
-{
- unsigned int temp;
-
- __asm__ __volatile__(
- "1: llock %0, [%1] \n"
- " add %0, %0, %2 \n"
- " scond %0, [%1] \n"
- " bnz 1b \n"
- : "=&r"(temp) /* Early clobber, to prevent reg reuse */
- : "r"(&v->counter), "ir"(i)
- : "cc");
-}
-
-static inline void atomic_sub(int i, atomic_t *v)
-{
- unsigned int temp;
-
- __asm__ __volatile__(
- "1: llock %0, [%1] \n"
- " sub %0, %0, %2 \n"
- " scond %0, [%1] \n"
- " bnz 1b \n"
- : "=&r"(temp)
- : "r"(&v->counter), "ir"(i)
- : "cc");
-}
-
-/* add and also return the new value */
-static inline int atomic_add_return(int i, atomic_t *v)
-{
- unsigned int temp;
-
- __asm__ __volatile__(
- "1: llock %0, [%1] \n"
- " add %0, %0, %2 \n"
- " scond %0, [%1] \n"
- " bnz 1b \n"
- : "=&r"(temp)
- : "r"(&v->counter), "ir"(i)
- : "cc");
-
- return temp;
-}
-
-static inline int atomic_sub_return(int i, atomic_t *v)
-{
- unsigned int temp;
-
- __asm__ __volatile__(
- "1: llock %0, [%1] \n"
- " sub %0, %0, %2 \n"
- " scond %0, [%1] \n"
- " bnz 1b \n"
- : "=&r"(temp)
- : "r"(&v->counter), "ir"(i)
- : "cc");
-
- return temp;
-}
-
-static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
-{
- unsigned int temp;
-
- __asm__ __volatile__(
- "1: llock %0, [%1] \n"
- " bic %0, %0, %2 \n"
- " scond %0, [%1] \n"
- " bnz 1b \n"
- : "=&r"(temp)
- : "r"(addr), "ir"(mask)
- : "cc");
+#define ATOMIC_OP(op, c_op, asm_op) \
+static inline void atomic_##op(int i, atomic_t *v) \
+{ \
+ unsigned int temp; \
+ \
+ __asm__ __volatile__( \
+ "1: llock %0, [%1] \n" \
+ " " #asm_op " %0, %0, %2 \n" \
+ " scond %0, [%1] \n" \
+ " bnz 1b \n" \
+ : "=&r"(temp) /* Early clobber, to prevent reg reuse */ \
+ : "r"(&v->counter), "ir"(i) \
+ : "cc"); \
+} \
+
+#define ATOMIC_OP_RETURN(op, c_op, asm_op) \
+static inline int atomic_##op##_return(int i, atomic_t *v) \
+{ \
+ unsigned int temp; \
+ \
+ __asm__ __volatile__( \
+ "1: llock %0, [%1] \n" \
+ " " #asm_op " %0, %0, %2 \n" \
+ " scond %0, [%1] \n" \
+ " bnz 1b \n" \
+ : "=&r"(temp) \
+ : "r"(&v->counter), "ir"(i) \
+ : "cc"); \
+ \
+ return temp; \
}

#else /* !CONFIG_ARC_HAS_LLSC */
@@ -126,6 +83,7 @@ static inline void atomic_set(atomic_t *v, int i)
v->counter = i;
atomic_ops_unlock(flags);
}
+
#endif

/*
@@ -133,62 +91,46 @@ static inline void atomic_set(atomic_t *v, int i)
* Locking would change to irq-disabling only (UP) and spinlocks (SMP)
*/

-static inline void atomic_add(int i, atomic_t *v)
-{
- unsigned long flags;
-
- atomic_ops_lock(flags);
- v->counter += i;
- atomic_ops_unlock(flags);
+#define ATOMIC_OP(op, c_op, asm_op) \
+static inline void atomic_##op(int i, atomic_t *v) \
+{ \
+ unsigned long flags; \
+ \
+ atomic_ops_lock(flags); \
+ v->counter c_op i; \
+ atomic_ops_unlock(flags); \
}

-static inline void atomic_sub(int i, atomic_t *v)
-{
- unsigned long flags;
-
- atomic_ops_lock(flags);
- v->counter -= i;
- atomic_ops_unlock(flags);
+#define ATOMIC_OP_RETURN(op, c_op) \
+static inline int atomic_##op##_return(int i, atomic_t *v) \
+{ \
+ unsigned long flags; \
+ unsigned long temp; \
+ \
+ atomic_ops_lock(flags); \
+ temp = v->counter; \
+ temp c_op i; \
+ v->counter = temp; \
+ atomic_ops_unlock(flags); \
+ \
+ return temp; \
}

-static inline int atomic_add_return(int i, atomic_t *v)
-{
- unsigned long flags;
- unsigned long temp;
-
- atomic_ops_lock(flags);
- temp = v->counter;
- temp += i;
- v->counter = temp;
- atomic_ops_unlock(flags);
-
- return temp;
-}
-
-static inline int atomic_sub_return(int i, atomic_t *v)
-{
- unsigned long flags;
- unsigned long temp;
-
- atomic_ops_lock(flags);
- temp = v->counter;
- temp -= i;
- v->counter = temp;
- atomic_ops_unlock(flags);
+#endif /* !CONFIG_ARC_HAS_LLSC */

- return temp;
-}
+#define ATOMIC_OPS(op, c_op, asm_op) \
+ ATOMIC_OP(op, c_op, asm_op) \
+ ATOMIC_OP_RETURN(op, c_op, asm_op)

-static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
-{
- unsigned long flags;
+ATOMIC_OPS(add, +=, add)
+ATOMIC_OPS(sub, -=, sub)
+ATOMIC_OP(and, &=, and)

- atomic_ops_lock(flags);
- *addr &= ~mask;
- atomic_ops_unlock(flags);
-}
+#define atomic_clear_mask(mask, v) atomic_and(~(mask), (v))

-#endif /* !CONFIG_ARC_HAS_LLSC */
+#undef ATOMIC_OPS
+#undef ATOMIC_OP_RETURN
+#undef ATOMIC_OP

/**
* __atomic_add_unless - add unless the number is a given value

\
 
 \ /
  Last update: 2015-07-15 12:01    [W:1.872 / U:0.164 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site