* [RFC local_t removal V2 1/3] Remove unused local.h functions
2010-01-07 22:35 [RFC local_t removal V2 0/3] Remove local_t Christoph Lameter
@ 2010-01-07 22:35 ` Christoph Lameter
2010-01-07 22:35 ` [RFC local_t removal V2 2/3] Remove local_t type from tree Christoph Lameter
2010-01-07 22:35 ` [RFC local_t removal V2 3/3] Eliminate local_cmpxchg Christoph Lameter
2 siblings, 0 replies; 5+ messages in thread
From: Christoph Lameter @ 2010-01-07 22:35 UTC (permalink / raw)
To: Mathieu Desnoyers; +Cc: Tejun Heo, Mike Frysinger, Arnd Bergmann, linux-kernel
[-- Attachment #1: remove_unused_local.h --]
[-- Type: text/plain, Size: 21528 bytes --]
The ringbuffer logic is the last user of local.h and it uses only the
following functions and types:
local_t
local_set()
local_read()
local_add_return()
local_add()
local_sub()
local_inc()
local_dec()
local_cmpxchg()
Keep those and remove all other local.h functions
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
---
arch/alpha/include/asm/local.h | 61 -------------
arch/m32r/include/asm/local.h | 181 ---------------------------------------
arch/mips/include/asm/local.h | 120 -------------------------
arch/powerpc/include/asm/local.h | 133 ----------------------------
arch/x86/include/asm/local.h | 118 -------------------------
include/asm-generic/local.h | 16 ---
6 files changed, 3 insertions(+), 626 deletions(-)
Index: linux-2.6/arch/powerpc/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/powerpc/include/asm/local.h 2010-01-07 16:05:53.000000000 -0600
+++ linux-2.6/arch/powerpc/include/asm/local.h 2010-01-07 16:26:26.000000000 -0600
@@ -36,140 +36,7 @@ static __inline__ long local_add_return(
return t;
}
-#define local_add_negative(a, l) (local_add_return((a), (l)) < 0)
-
-static __inline__ long local_sub_return(long a, local_t *l)
-{
- long t;
-
- __asm__ __volatile__(
-"1:" PPC_LLARX "%0,0,%2 # local_sub_return\n\
- subf %0,%1,%0\n"
- PPC405_ERR77(0,%2)
- PPC_STLCX "%0,0,%2 \n\
- bne- 1b"
- : "=&r" (t)
- : "r" (a), "r" (&(l->a.counter))
- : "cc", "memory");
-
- return t;
-}
-
-static __inline__ long local_inc_return(local_t *l)
-{
- long t;
-
- __asm__ __volatile__(
-"1:" PPC_LLARX "%0,0,%1 # local_inc_return\n\
- addic %0,%0,1\n"
- PPC405_ERR77(0,%1)
- PPC_STLCX "%0,0,%1 \n\
- bne- 1b"
- : "=&r" (t)
- : "r" (&(l->a.counter))
- : "cc", "xer", "memory");
-
- return t;
-}
-
-/*
- * local_inc_and_test - increment and test
- * @l: pointer of type local_t
- *
- * Atomically increments @l by 1
- * and returns true if the result is zero, or false for all
- * other cases.
- */
-#define local_inc_and_test(l) (local_inc_return(l) == 0)
-
-static __inline__ long local_dec_return(local_t *l)
-{
- long t;
-
- __asm__ __volatile__(
-"1:" PPC_LLARX "%0,0,%1 # local_dec_return\n\
- addic %0,%0,-1\n"
- PPC405_ERR77(0,%1)
- PPC_STLCX "%0,0,%1\n\
- bne- 1b"
- : "=&r" (t)
- : "r" (&(l->a.counter))
- : "cc", "xer", "memory");
-
- return t;
-}
-
#define local_cmpxchg(l, o, n) \
(cmpxchg_local(&((l)->a.counter), (o), (n)))
-#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
-
-/**
- * local_add_unless - add unless the number is a given value
- * @l: pointer of type local_t
- * @a: the amount to add to v...
- * @u: ...unless v is equal to u.
- *
- * Atomically adds @a to @l, so long as it was not @u.
- * Returns non-zero if @l was not @u, and zero otherwise.
- */
-static __inline__ int local_add_unless(local_t *l, long a, long u)
-{
- long t;
-
- __asm__ __volatile__ (
-"1:" PPC_LLARX "%0,0,%1 # local_add_unless\n\
- cmpw 0,%0,%3 \n\
- beq- 2f \n\
- add %0,%2,%0 \n"
- PPC405_ERR77(0,%2)
- PPC_STLCX "%0,0,%1 \n\
- bne- 1b \n"
-" subf %0,%2,%0 \n\
-2:"
- : "=&r" (t)
- : "r" (&(l->a.counter)), "r" (a), "r" (u)
- : "cc", "memory");
-
- return t != u;
-}
-
-#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
-
-#define local_sub_and_test(a, l) (local_sub_return((a), (l)) == 0)
-#define local_dec_and_test(l) (local_dec_return((l)) == 0)
-
-/*
- * Atomically test *l and decrement if it is greater than 0.
- * The function returns the old value of *l minus 1.
- */
-static __inline__ long local_dec_if_positive(local_t *l)
-{
- long t;
-
- __asm__ __volatile__(
-"1:" PPC_LLARX "%0,0,%1 # local_dec_if_positive\n\
- cmpwi %0,1\n\
- addi %0,%0,-1\n\
- blt- 2f\n"
- PPC405_ERR77(0,%1)
- PPC_STLCX "%0,0,%1\n\
- bne- 1b"
- "\n\
-2:" : "=&b" (t)
- : "r" (&(l->a.counter))
- : "cc", "memory");
-
- return t;
-}
-
-/* Use these for per-cpu local_t variables: on some archs they are
- * much more efficient than these naive implementations. Note they take
- * a variable, not an address.
- */
-
-#define __local_inc(l) ((l)->a.counter++)
-#define __local_dec(l) ((l)->a.counter++)
-#define __local_add(i,l) ((l)->a.counter+=(i))
-#define __local_sub(i,l) ((l)->a.counter-=(i))
#endif /* _ARCH_POWERPC_LOCAL_H */
Index: linux-2.6/arch/x86/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/local.h 2010-01-07 16:05:53.000000000 -0600
+++ linux-2.6/arch/x86/include/asm/local.h 2010-01-07 16:26:26.000000000 -0600
@@ -43,80 +43,6 @@ static inline void local_sub(long i, loc
}
/**
- * local_sub_and_test - subtract value from variable and test result
- * @i: integer value to subtract
- * @l: pointer to type local_t
- *
- * Atomically subtracts @i from @l and returns
- * true if the result is zero, or false for all
- * other cases.
- */
-static inline int local_sub_and_test(long i, local_t *l)
-{
- unsigned char c;
-
- asm volatile(_ASM_SUB "%2,%0; sete %1"
- : "+m" (l->a.counter), "=qm" (c)
- : "ir" (i) : "memory");
- return c;
-}
-
-/**
- * local_dec_and_test - decrement and test
- * @l: pointer to type local_t
- *
- * Atomically decrements @l by 1 and
- * returns true if the result is 0, or false for all other
- * cases.
- */
-static inline int local_dec_and_test(local_t *l)
-{
- unsigned char c;
-
- asm volatile(_ASM_DEC "%0; sete %1"
- : "+m" (l->a.counter), "=qm" (c)
- : : "memory");
- return c != 0;
-}
-
-/**
- * local_inc_and_test - increment and test
- * @l: pointer to type local_t
- *
- * Atomically increments @l by 1
- * and returns true if the result is zero, or false for all
- * other cases.
- */
-static inline int local_inc_and_test(local_t *l)
-{
- unsigned char c;
-
- asm volatile(_ASM_INC "%0; sete %1"
- : "+m" (l->a.counter), "=qm" (c)
- : : "memory");
- return c != 0;
-}
-
-/**
- * local_add_negative - add and test if negative
- * @i: integer value to add
- * @l: pointer to type local_t
- *
- * Atomically adds @i to @l and returns true
- * if the result is negative, or false when
- * result is greater than or equal to zero.
- */
-static inline int local_add_negative(long i, local_t *l)
-{
- unsigned char c;
-
- asm volatile(_ASM_ADD "%2,%0; sets %1"
- : "+m" (l->a.counter), "=qm" (c)
- : "ir" (i) : "memory");
- return c;
-}
-
-/**
* local_add_return - add and return
* @i: integer value to add
* @l: pointer to type local_t
@@ -148,51 +74,7 @@ no_xadd: /* Legacy 386 processor */
#endif
}
-static inline long local_sub_return(long i, local_t *l)
-{
- return local_add_return(-i, l);
-}
-
-#define local_inc_return(l) (local_add_return(1, l))
-#define local_dec_return(l) (local_sub_return(1, l))
-
#define local_cmpxchg(l, o, n) \
(cmpxchg_local(&((l)->a.counter), (o), (n)))
-/* Always has a lock prefix */
-#define local_xchg(l, n) (xchg(&((l)->a.counter), (n)))
-
-/**
- * local_add_unless - add unless the number is a given value
- * @l: pointer of type local_t
- * @a: the amount to add to l...
- * @u: ...unless l is equal to u.
- *
- * Atomically adds @a to @l, so long as it was not @u.
- * Returns non-zero if @l was not @u, and zero otherwise.
- */
-#define local_add_unless(l, a, u) \
-({ \
- long c, old; \
- c = local_read((l)); \
- for (;;) { \
- if (unlikely(c == (u))) \
- break; \
- old = local_cmpxchg((l), c, c + (a)); \
- if (likely(old == c)) \
- break; \
- c = old; \
- } \
- c != (u); \
-})
-#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
-
-/* On x86_32, these are no better than the atomic variants.
- * On x86-64 these are better than the atomic variants on SMP kernels
- * because they dont use a lock prefix.
- */
-#define __local_inc(l) local_inc(l)
-#define __local_dec(l) local_dec(l)
-#define __local_add(i, l) local_add((i), (l))
-#define __local_sub(i, l) local_sub((i), (l))
#endif /* _ASM_X86_LOCAL_H */
Index: linux-2.6/include/asm-generic/local.h
===================================================================
--- linux-2.6.orig/include/asm-generic/local.h 2010-01-07 16:05:53.000000000 -0600
+++ linux-2.6/include/asm-generic/local.h 2010-01-07 16:26:26.000000000 -0600
@@ -32,24 +32,8 @@ typedef struct
#define local_add(i,l) atomic_long_add((i),(&(l)->a))
#define local_sub(i,l) atomic_long_sub((i),(&(l)->a))
-#define local_sub_and_test(i, l) atomic_long_sub_and_test((i), (&(l)->a))
-#define local_dec_and_test(l) atomic_long_dec_and_test(&(l)->a)
-#define local_inc_and_test(l) atomic_long_inc_and_test(&(l)->a)
-#define local_add_negative(i, l) atomic_long_add_negative((i), (&(l)->a))
#define local_add_return(i, l) atomic_long_add_return((i), (&(l)->a))
-#define local_sub_return(i, l) atomic_long_sub_return((i), (&(l)->a))
-#define local_inc_return(l) atomic_long_inc_return(&(l)->a)
#define local_cmpxchg(l, o, n) atomic_long_cmpxchg((&(l)->a), (o), (n))
-#define local_xchg(l, n) atomic_long_xchg((&(l)->a), (n))
-#define local_add_unless(l, _a, u) atomic_long_add_unless((&(l)->a), (_a), (u))
-#define local_inc_not_zero(l) atomic_long_inc_not_zero(&(l)->a)
-
-/* Non-atomic variants, ie. preemption disabled and won't be touched
- * in interrupt, etc. Some archs can optimize this case well. */
-#define __local_inc(l) local_set((l), local_read(l) + 1)
-#define __local_dec(l) local_set((l), local_read(l) - 1)
-#define __local_add(i,l) local_set((l), local_read(l) + (i))
-#define __local_sub(i,l) local_set((l), local_read(l) - (i))
#endif /* _ASM_GENERIC_LOCAL_H */
Index: linux-2.6/arch/alpha/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/alpha/include/asm/local.h 2010-01-07 16:05:53.000000000 -0600
+++ linux-2.6/arch/alpha/include/asm/local.h 2010-01-07 16:26:26.000000000 -0600
@@ -34,68 +34,7 @@ static __inline__ long local_add_return(
return result;
}
-static __inline__ long local_sub_return(long i, local_t * l)
-{
- long temp, result;
- __asm__ __volatile__(
- "1: ldq_l %0,%1\n"
- " subq %0,%3,%2\n"
- " subq %0,%3,%0\n"
- " stq_c %0,%1\n"
- " beq %0,2f\n"
- ".subsection 2\n"
- "2: br 1b\n"
- ".previous"
- :"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
- :"Ir" (i), "m" (l->a.counter) : "memory");
- return result;
-}
-
#define local_cmpxchg(l, o, n) \
(cmpxchg_local(&((l)->a.counter), (o), (n)))
-#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
-
-/**
- * local_add_unless - add unless the number is a given value
- * @l: pointer of type local_t
- * @a: the amount to add to l...
- * @u: ...unless l is equal to u.
- *
- * Atomically adds @a to @l, so long as it was not @u.
- * Returns non-zero if @l was not @u, and zero otherwise.
- */
-#define local_add_unless(l, a, u) \
-({ \
- long c, old; \
- c = local_read(l); \
- for (;;) { \
- if (unlikely(c == (u))) \
- break; \
- old = local_cmpxchg((l), c, c + (a)); \
- if (likely(old == c)) \
- break; \
- c = old; \
- } \
- c != (u); \
-})
-#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
-
-#define local_add_negative(a, l) (local_add_return((a), (l)) < 0)
-
-#define local_dec_return(l) local_sub_return(1,(l))
-
-#define local_inc_return(l) local_add_return(1,(l))
-
-#define local_sub_and_test(i,l) (local_sub_return((i), (l)) == 0)
-
-#define local_inc_and_test(l) (local_add_return(1, (l)) == 0)
-
-#define local_dec_and_test(l) (local_sub_return(1, (l)) == 0)
-
-/* Verify if faster than atomic ops */
-#define __local_inc(l) ((l)->a.counter++)
-#define __local_dec(l) ((l)->a.counter++)
-#define __local_add(i,l) ((l)->a.counter+=(i))
-#define __local_sub(i,l) ((l)->a.counter-=(i))
#endif /* _ALPHA_LOCAL_H */
Index: linux-2.6/arch/m32r/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/m32r/include/asm/local.h 2010-01-07 16:05:53.000000000 -0600
+++ linux-2.6/arch/m32r/include/asm/local.h 2010-01-07 16:26:26.000000000 -0600
@@ -78,37 +78,6 @@ static inline long local_add_return(long
}
/**
- * local_sub_return - subtract long from local variable and return it
- * @i: long value to subtract
- * @l: pointer of type local_t
- *
- * Atomically subtracts @i from @l and return (@l - @i).
- */
-static inline long local_sub_return(long i, local_t *l)
-{
- unsigned long flags;
- long result;
-
- local_irq_save(flags);
- __asm__ __volatile__ (
- "# local_sub_return \n\t"
- DCACHE_CLEAR("%0", "r4", "%1")
- "ld %0, @%1; \n\t"
- "sub %0, %2; \n\t"
- "st %0, @%1; \n\t"
- : "=&r" (result)
- : "r" (&l->counter), "r" (i)
- : "memory"
-#ifdef CONFIG_CHIP_M32700_TS1
- , "r4"
-#endif /* CONFIG_CHIP_M32700_TS1 */
- );
- local_irq_restore(flags);
-
- return result;
-}
-
-/**
* local_add - add long to local variable
* @i: long value to add
* @l: pointer of type local_t
@@ -124,78 +93,7 @@ static inline long local_sub_return(long
*
* Atomically subtracts @i from @l.
*/
-#define local_sub(i, l) ((void) local_sub_return((i), (l)))
-
-/**
- * local_sub_and_test - subtract value from variable and test result
- * @i: integer value to subtract
- * @l: pointer of type local_t
- *
- * Atomically subtracts @i from @l and returns
- * true if the result is zero, or false for all
- * other cases.
- */
-#define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0)
-
-/**
- * local_inc_return - increment local variable and return it
- * @l: pointer of type local_t
- *
- * Atomically increments @l by 1 and returns the result.
- */
-static inline long local_inc_return(local_t *l)
-{
- unsigned long flags;
- long result;
-
- local_irq_save(flags);
- __asm__ __volatile__ (
- "# local_inc_return \n\t"
- DCACHE_CLEAR("%0", "r4", "%1")
- "ld %0, @%1; \n\t"
- "addi %0, #1; \n\t"
- "st %0, @%1; \n\t"
- : "=&r" (result)
- : "r" (&l->counter)
- : "memory"
-#ifdef CONFIG_CHIP_M32700_TS1
- , "r4"
-#endif /* CONFIG_CHIP_M32700_TS1 */
- );
- local_irq_restore(flags);
-
- return result;
-}
-
-/**
- * local_dec_return - decrement local variable and return it
- * @l: pointer of type local_t
- *
- * Atomically decrements @l by 1 and returns the result.
- */
-static inline long local_dec_return(local_t *l)
-{
- unsigned long flags;
- long result;
-
- local_irq_save(flags);
- __asm__ __volatile__ (
- "# local_dec_return \n\t"
- DCACHE_CLEAR("%0", "r4", "%1")
- "ld %0, @%1; \n\t"
- "addi %0, #-1; \n\t"
- "st %0, @%1; \n\t"
- : "=&r" (result)
- : "r" (&l->counter)
- : "memory"
-#ifdef CONFIG_CHIP_M32700_TS1
- , "r4"
-#endif /* CONFIG_CHIP_M32700_TS1 */
- );
- local_irq_restore(flags);
-
- return result;
-}
+#define local_sub(i, l) ((void) local_add_return(-(i), (l)))
/**
* local_inc - increment local variable
@@ -203,7 +101,7 @@ static inline long local_dec_return(loca
*
* Atomically increments @l by 1.
*/
-#define local_inc(l) ((void)local_inc_return(l))
+#define local_inc(l) local_add(1, (l))
/**
* local_dec - decrement local variable
@@ -211,67 +109,9 @@ static inline long local_dec_return(loca
*
* Atomically decrements @l by 1.
*/
-#define local_dec(l) ((void)local_dec_return(l))
-
-/**
- * local_inc_and_test - increment and test
- * @l: pointer of type local_t
- *
- * Atomically increments @l by 1
- * and returns true if the result is zero, or false for all
- * other cases.
- */
-#define local_inc_and_test(l) (local_inc_return(l) == 0)
-
-/**
- * local_dec_and_test - decrement and test
- * @l: pointer of type local_t
- *
- * Atomically decrements @l by 1 and
- * returns true if the result is 0, or false for all
- * other cases.
- */
-#define local_dec_and_test(l) (local_dec_return(l) == 0)
-
-/**
- * local_add_negative - add and test if negative
- * @l: pointer of type local_t
- * @i: integer value to add
- *
- * Atomically adds @i to @l and returns true
- * if the result is negative, or false when
- * result is greater than or equal to zero.
- */
-#define local_add_negative(i, l) (local_add_return((i), (l)) < 0)
+#define local_dec(l) local_sub(1, (l))
#define local_cmpxchg(l, o, n) (cmpxchg_local(&((l)->counter), (o), (n)))
-#define local_xchg(v, new) (xchg_local(&((l)->counter), new))
-
-/**
- * local_add_unless - add unless the number is a given value
- * @l: pointer of type local_t
- * @a: the amount to add to l...
- * @u: ...unless l is equal to u.
- *
- * Atomically adds @a to @l, so long as it was not @u.
- * Returns non-zero if @l was not @u, and zero otherwise.
- */
-static inline int local_add_unless(local_t *l, long a, long u)
-{
- long c, old;
- c = local_read(l);
- for (;;) {
- if (unlikely(c == (u)))
- break;
- old = local_cmpxchg((l), c, c + (a));
- if (likely(old == c))
- break;
- c = old;
- }
- return c != (u);
-}
-
-#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
static inline void local_clear_mask(unsigned long mask, local_t *addr)
{
@@ -323,19 +163,4 @@ static inline void local_set_mask(unsign
#define smp_mb__before_local_inc() barrier()
#define smp_mb__after_local_inc() barrier()
-/* Use these for per-cpu local_t variables: on some archs they are
- * much more efficient than these naive implementations. Note they take
- * a variable, not an address.
- */
-
-#define __local_inc(l) ((l)->a.counter++)
-#define __local_dec(l) ((l)->a.counter++)
-#define __local_add(i, l) ((l)->a.counter += (i))
-#define __local_sub(i, l) ((l)->a.counter -= (i))
-
-/* Use these for per-cpu local_t variables: on some archs they are
- * much more efficient than these naive implementations. Note they take
- * a variable, not an address.
- */
-
#endif /* __M32R_LOCAL_H */
Index: linux-2.6/arch/mips/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/mips/include/asm/local.h 2010-01-07 16:06:42.000000000 -0600
+++ linux-2.6/arch/mips/include/asm/local.h 2010-01-07 16:26:26.000000000 -0600
@@ -70,127 +70,7 @@ static __inline__ long local_add_return(
return result;
}
-static __inline__ long local_sub_return(long i, local_t * l)
-{
- unsigned long result;
-
- if (kernel_uses_llsc && R10000_LLSC_WAR) {
- unsigned long temp;
-
- __asm__ __volatile__(
- " .set mips3 \n"
- "1:" __LL "%1, %2 # local_sub_return \n"
- " subu %0, %1, %3 \n"
- __SC "%0, %2 \n"
- " beqzl %0, 1b \n"
- " subu %0, %1, %3 \n"
- " .set mips0 \n"
- : "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
- : "Ir" (i), "m" (l->a.counter)
- : "memory");
- } else if (kernel_uses_llsc) {
- unsigned long temp;
-
- __asm__ __volatile__(
- " .set mips3 \n"
- "1:" __LL "%1, %2 # local_sub_return \n"
- " subu %0, %1, %3 \n"
- __SC "%0, %2 \n"
- " beqz %0, 1b \n"
- " subu %0, %1, %3 \n"
- " .set mips0 \n"
- : "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
- : "Ir" (i), "m" (l->a.counter)
- : "memory");
- } else {
- unsigned long flags;
-
- local_irq_save(flags);
- result = l->a.counter;
- result -= i;
- l->a.counter = result;
- local_irq_restore(flags);
- }
-
- return result;
-}
-
#define local_cmpxchg(l, o, n) \
((long)cmpxchg_local(&((l)->a.counter), (o), (n)))
-#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
-
-/**
- * local_add_unless - add unless the number is a given value
- * @l: pointer of type local_t
- * @a: the amount to add to l...
- * @u: ...unless l is equal to u.
- *
- * Atomically adds @a to @l, so long as it was not @u.
- * Returns non-zero if @l was not @u, and zero otherwise.
- */
-#define local_add_unless(l, a, u) \
-({ \
- long c, old; \
- c = local_read(l); \
- while (c != (u) && (old = local_cmpxchg((l), c, c + (a))) != c) \
- c = old; \
- c != (u); \
-})
-#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
-
-#define local_dec_return(l) local_sub_return(1, (l))
-#define local_inc_return(l) local_add_return(1, (l))
-
-/*
- * local_sub_and_test - subtract value from variable and test result
- * @i: integer value to subtract
- * @l: pointer of type local_t
- *
- * Atomically subtracts @i from @l and returns
- * true if the result is zero, or false for all
- * other cases.
- */
-#define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0)
-
-/*
- * local_inc_and_test - increment and test
- * @l: pointer of type local_t
- *
- * Atomically increments @l by 1
- * and returns true if the result is zero, or false for all
- * other cases.
- */
-#define local_inc_and_test(l) (local_inc_return(l) == 0)
-
-/*
- * local_dec_and_test - decrement by 1 and test
- * @l: pointer of type local_t
- *
- * Atomically decrements @l by 1 and
- * returns true if the result is 0, or false for all other
- * cases.
- */
-#define local_dec_and_test(l) (local_sub_return(1, (l)) == 0)
-
-/*
- * local_add_negative - add and test if negative
- * @l: pointer of type local_t
- * @i: integer value to add
- *
- * Atomically adds @i to @l and returns true
- * if the result is negative, or false when
- * result is greater than or equal to zero.
- */
-#define local_add_negative(i, l) (local_add_return(i, (l)) < 0)
-
-/* Use these for per-cpu local_t variables: on some archs they are
- * much more efficient than these naive implementations. Note they take
- * a variable, not an address.
- */
-
-#define __local_inc(l) ((l)->a.counter++)
-#define __local_dec(l) ((l)->a.counter++)
-#define __local_add(i, l) ((l)->a.counter+=(i))
-#define __local_sub(i, l) ((l)->a.counter-=(i))
#endif /* _ARCH_MIPS_LOCAL_H */
--
^ permalink raw reply [flat|nested] 5+ messages in thread* [RFC local_t removal V2 2/3] Remove local_t type from tree.
2010-01-07 22:35 [RFC local_t removal V2 0/3] Remove local_t Christoph Lameter
2010-01-07 22:35 ` [RFC local_t removal V2 1/3] Remove unused local.h functions Christoph Lameter
@ 2010-01-07 22:35 ` Christoph Lameter
2010-01-08 8:55 ` Arnd Bergmann
2010-01-07 22:35 ` [RFC local_t removal V2 3/3] Eliminate local_cmpxchg Christoph Lameter
2 siblings, 1 reply; 5+ messages in thread
From: Christoph Lameter @ 2010-01-07 22:35 UTC (permalink / raw)
To: Mathieu Desnoyers; +Cc: Tejun Heo, Mike Frysinger, Arnd Bergmann, linux-kernel
[-- Attachment #1: remove_local_t --]
[-- Type: text/plain, Size: 24493 bytes --]
It would be better if local ops would generically work on any scalar. local_t
only allows the use of long. local_t also requires initializers and a read
function that never does anything aside from setting or reading a variable.
Remove local_t and replace with long. For now the API still only supports
a single type but asm-generic/local.h shows how it can be genericized similar
to what cmpxchg_local() does.
With that we can get rid of local_read/set and LOCAL_INIT too.
We need to update the ringbuffer users to no longer refer to these functions.
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
---
arch/alpha/include/asm/local.h | 29 +++------
arch/m32r/include/asm/local.h | 37 +-----------
arch/mips/include/asm/local.h | 39 ++++---------
arch/powerpc/include/asm/local.h | 26 ++------
arch/x86/include/asm/local.h | 35 ++++-------
include/asm-generic/local.h | 66 +++++++++++++---------
kernel/trace/ring_buffer.c | 104 +++++++++++++++++------------------
kernel/trace/ring_buffer_benchmark.c | 4 -
8 files changed, 141 insertions(+), 199 deletions(-)
Index: linux-2.6/arch/powerpc/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/powerpc/include/asm/local.h 2010-01-07 16:09:45.000000000 -0600
+++ linux-2.6/arch/powerpc/include/asm/local.h 2010-01-07 16:25:53.000000000 -0600
@@ -4,22 +4,7 @@
#include <linux/percpu.h>
#include <asm/atomic.h>
-typedef struct
-{
- atomic_long_t a;
-} local_t;
-
-#define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
-
-#define local_read(l) atomic_long_read(&(l)->a)
-#define local_set(l,i) atomic_long_set(&(l)->a, (i))
-
-#define local_add(i,l) atomic_long_add((i),(&(l)->a))
-#define local_sub(i,l) atomic_long_sub((i),(&(l)->a))
-#define local_inc(l) atomic_long_inc(&(l)->a)
-#define local_dec(l) atomic_long_dec(&(l)->a)
-
-static __inline__ long local_add_return(long a, local_t *l)
+static __inline__ long local_add_return(long a, long *l)
{
long t;
@@ -30,13 +15,18 @@ static __inline__ long local_add_return(
PPC_STLCX "%0,0,%2 \n\
bne- 1b"
: "=&r" (t)
- : "r" (a), "r" (&(l->a.counter))
+ : "r" (a), "r" (*l)
: "cc", "memory");
return t;
}
+#define local_add(i, l) local_add_return((i), (l))
+#define local_sub(i, l) local_add_return(-(i), (l))
+#define local_inc(l) local_add_return(1, (l))
+#define local_dec(l) local_add_return(-1, (l))
+
#define local_cmpxchg(l, o, n) \
- (cmpxchg_local(&((l)->a.counter), (o), (n)))
+ (cmpxchg_local((l), (o), (n)))
#endif /* _ARCH_POWERPC_LOCAL_H */
Index: linux-2.6/arch/x86/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/local.h 2010-01-07 16:09:45.000000000 -0600
+++ linux-2.6/arch/x86/include/asm/local.h 2010-01-07 16:25:54.000000000 -0600
@@ -7,38 +7,29 @@
#include <asm/atomic.h>
#include <asm/asm.h>
-typedef struct {
- atomic_long_t a;
-} local_t;
-
-#define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
-
-#define local_read(l) atomic_long_read(&(l)->a)
-#define local_set(l, i) atomic_long_set(&(l)->a, (i))
-
-static inline void local_inc(local_t *l)
+static inline void local_inc(long *l)
{
asm volatile(_ASM_INC "%0"
- : "+m" (l->a.counter));
+ : "+m" (*l));
}
-static inline void local_dec(local_t *l)
+static inline void local_dec(long *l)
{
asm volatile(_ASM_DEC "%0"
- : "+m" (l->a.counter));
+ : "+m" (*l));
}
-static inline void local_add(long i, local_t *l)
+static inline void local_add(long i, long *l)
{
asm volatile(_ASM_ADD "%1,%0"
- : "+m" (l->a.counter)
+ : "+m" (*l)
: "ir" (i));
}
-static inline void local_sub(long i, local_t *l)
+static inline void local_sub(long i, long *l)
{
asm volatile(_ASM_SUB "%1,%0"
- : "+m" (l->a.counter)
+ : "+m" (*l)
: "ir" (i));
}
@@ -49,7 +40,7 @@ static inline void local_sub(long i, loc
*
* Atomically adds @i to @l and returns @i + @l
*/
-static inline long local_add_return(long i, local_t *l)
+static inline long local_add_return(long i, long *l)
{
long __i;
#ifdef CONFIG_M386
@@ -60,21 +51,21 @@ static inline long local_add_return(long
/* Modern 486+ processor */
__i = i;
asm volatile(_ASM_XADD "%0, %1;"
- : "+r" (i), "+m" (l->a.counter)
+ : "+r" (i), "+m" (*l)
: : "memory");
return i + __i;
#ifdef CONFIG_M386
no_xadd: /* Legacy 386 processor */
local_irq_save(flags);
- __i = local_read(l);
- local_set(l, i + __i);
+ __i = *l;
+ *l = i + __i;
local_irq_restore(flags);
return i + __i;
#endif
}
#define local_cmpxchg(l, o, n) \
- (cmpxchg_local(&((l)->a.counter), (o), (n)))
+ (cmpxchg_local((l), (o), (n)))
#endif /* _ASM_X86_LOCAL_H */
Index: linux-2.6/include/asm-generic/local.h
===================================================================
--- linux-2.6.orig/include/asm-generic/local.h 2010-01-07 16:09:45.000000000 -0600
+++ linux-2.6/include/asm-generic/local.h 2010-01-07 16:26:19.000000000 -0600
@@ -1,39 +1,53 @@
#ifndef _ASM_GENERIC_LOCAL_H
#define _ASM_GENERIC_LOCAL_H
-#include <linux/percpu.h>
-#include <asm/atomic.h>
#include <asm/types.h>
+#include <linux/kernel.h>
/*
- * A signed long type for operations which are atomic for a single CPU.
- * Usually used in combination with per-cpu variables.
+ * The whole point here is to allow the use of atomic wrt IRQ operations of
+ * some cpus. local_xx ops allow to exploit such operations.
*
- * This is the default implementation, which uses atomic_long_t. Which is
- * rather pointless. The whole point behind local_t is that some processors
- * can perform atomic adds and subtracts in a manner which is atomic wrt IRQs
- * running on this CPU. local_t allows exploitation of such capabilities.
+ * Note that the percpu subsystem contains similar operations that also
+ * perform relocation to the per cpu area of the current processor in the
+ * same instruction. This guarantees that each processor has its own variable.
+ *
+ * The use of these operations here requires that the user has made his
+ * own arrangements to guarantee that concurrrent modifications / accesses
+ * to the specified variable from different processors does not occur.
*/
-/* Implement in terms of atomics. */
-
-/* Don't use typedef: don't want them to be mixed with atomic_t's. */
-typedef struct
+/*
+ * Generic version of __add_return_local (disables interrupts). Takes an
+ * unsigned long parameter, supporting various types of architectures.
+ */
+static inline unsigned long __local_add_return(volatile void *ptr,
+ unsigned long value, size_t size)
{
- atomic_long_t a;
-} local_t;
-
-#define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
-
-#define local_read(l) atomic_long_read(&(l)->a)
-#define local_set(l,i) atomic_long_set((&(l)->a),(i))
-#define local_inc(l) atomic_long_inc(&(l)->a)
-#define local_dec(l) atomic_long_dec(&(l)->a)
-#define local_add(i,l) atomic_long_add((i),(&(l)->a))
-#define local_sub(i,l) atomic_long_sub((i),(&(l)->a))
+ unsigned long flags, r;
-#define local_add_return(i, l) atomic_long_add_return((i), (&(l)->a))
+ local_irq_save(flags);
+ switch (size) {
+ case 1: r = (*((u8 *)ptr) += value);
+ break;
+ case 2: r = (*((u16 *)ptr) += value);
+ break;
+ case 4: r = (*((u32 *)ptr) += value);
+ break;
+ case 8: r = (*((u64 *)ptr) += value);
+ break;
+ }
+ local_irq_restore(flags);
+ return r;
+}
+
+#define local_add_return(i, l) __local_add_return((l), (i), sizeof(*(l)))
+
+#define local_inc(l) local_add_return(1, (l))
+#define local_dec(l) local_add_return(-1, (l))
+#define local_add(i,l) local_add_return((i), (l))
+#define local_sub(i,l) local_add_return(-(i), (l))
-#define local_cmpxchg(l, o, n) atomic_long_cmpxchg((&(l)->a), (o), (n))
+#define local_cmpxchg(l, o, n) cmpxchg_local((l), (o), (n))
-#endif /* _ASM_GENERIC_LOCAL_H */
+#endif /* _ASM_GENERIC_LOCAL_i */
Index: linux-2.6/kernel/trace/ring_buffer.c
===================================================================
--- linux-2.6.orig/kernel/trace/ring_buffer.c 2010-01-07 16:09:45.000000000 -0600
+++ linux-2.6/kernel/trace/ring_buffer.c 2010-01-07 16:25:54.000000000 -0600
@@ -312,7 +312,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_event_data
struct buffer_data_page {
u64 time_stamp; /* page time stamp */
- local_t commit; /* write committed index */
+ long commit; /* write committed index */
unsigned char data[]; /* data of buffer page */
};
@@ -326,9 +326,9 @@ struct buffer_data_page {
*/
struct buffer_page {
struct list_head list; /* list of buffer pages */
- local_t write; /* index for next write */
+ long write; /* index for next write */
unsigned read; /* index for next read */
- local_t entries; /* entries on this page */
+ long entries; /* entries on this page */
struct buffer_data_page *page; /* Actual data page */
};
@@ -349,7 +349,7 @@ struct buffer_page {
static void rb_init_page(struct buffer_data_page *bpage)
{
- local_set(&bpage->commit, 0);
+ bpage->commit = 0;
}
/**
@@ -360,7 +360,7 @@ static void rb_init_page(struct buffer_d
*/
size_t ring_buffer_page_len(void *page)
{
- return local_read(&((struct buffer_data_page *)page)->commit)
+ return ((struct buffer_data_page *)page)->commit
+ BUF_PAGE_HDR_SIZE;
}
@@ -431,11 +431,11 @@ struct ring_buffer_per_cpu {
struct buffer_page *tail_page; /* write to tail */
struct buffer_page *commit_page; /* committed pages */
struct buffer_page *reader_page;
- local_t commit_overrun;
- local_t overrun;
- local_t entries;
- local_t committing;
- local_t commits;
+ long commit_overrun;
+ long overrun;
+ long entries;
+ long committing;
+ long commits;
unsigned long read;
u64 write_stamp;
u64 read_stamp;
@@ -861,7 +861,7 @@ static int rb_tail_page_update(struct ri
* it only can increment when a commit takes place. But that
* only happens in the outer most nested commit.
*/
- local_set(&next_page->page->commit, 0);
+ next_page->page->commit = 0;
old_tail = cmpxchg(&cpu_buffer->tail_page,
tail_page, next_page);
@@ -1394,17 +1394,17 @@ rb_iter_head_event(struct ring_buffer_it
static inline unsigned long rb_page_write(struct buffer_page *bpage)
{
- return local_read(&bpage->write) & RB_WRITE_MASK;
+ return bpage->write & RB_WRITE_MASK;
}
static inline unsigned rb_page_commit(struct buffer_page *bpage)
{
- return local_read(&bpage->page->commit);
+ return bpage->page->commit;
}
static inline unsigned long rb_page_entries(struct buffer_page *bpage)
{
- return local_read(&bpage->entries) & RB_WRITE_MASK;
+ return bpage->entries & RB_WRITE_MASK;
}
/* Size is determined by what has been commited */
@@ -1463,8 +1463,8 @@ rb_set_commit_to_write(struct ring_buffe
if (RB_WARN_ON(cpu_buffer,
rb_is_reader_page(cpu_buffer->tail_page)))
return;
- local_set(&cpu_buffer->commit_page->page->commit,
- rb_page_write(cpu_buffer->commit_page));
+ cpu_buffer->commit_page->page->commit =
+ rb_page_write(cpu_buffer->commit_page);
rb_inc_page(cpu_buffer, &cpu_buffer->commit_page);
cpu_buffer->write_stamp =
cpu_buffer->commit_page->page->time_stamp;
@@ -1474,10 +1474,10 @@ rb_set_commit_to_write(struct ring_buffe
while (rb_commit_index(cpu_buffer) !=
rb_page_write(cpu_buffer->commit_page)) {
- local_set(&cpu_buffer->commit_page->page->commit,
- rb_page_write(cpu_buffer->commit_page));
+ cpu_buffer->commit_page->page->commit =
+ rb_page_write(cpu_buffer->commit_page);
RB_WARN_ON(cpu_buffer,
- local_read(&cpu_buffer->commit_page->page->commit) &
+ cpu_buffer->commit_page->page->commit &
~RB_WRITE_MASK);
barrier();
}
@@ -1943,7 +1943,7 @@ rb_try_to_discard(struct ring_buffer_per
if (bpage->page == (void *)addr && rb_page_write(bpage) == old_index) {
unsigned long write_mask =
- local_read(&bpage->write) & ~RB_WRITE_MASK;
+ bpage->write & ~RB_WRITE_MASK;
/*
* This is on the tail page. It is possible that
* a write could come in and move the tail page
@@ -2039,14 +2039,14 @@ static void rb_end_commit(struct ring_bu
unsigned long commits;
if (RB_WARN_ON(cpu_buffer,
- !local_read(&cpu_buffer->committing)))
+ !cpu_buffer->committing))
return;
again:
- commits = local_read(&cpu_buffer->commits);
+ commits = cpu_buffer->commits;
/* synchronize with interrupts */
barrier();
- if (local_read(&cpu_buffer->committing) == 1)
+ if (cpu_buffer->committing == 1)
rb_set_commit_to_write(cpu_buffer);
local_dec(&cpu_buffer->committing);
@@ -2059,8 +2059,8 @@ static void rb_end_commit(struct ring_bu
* updating of the commit page and the clearing of the
* committing counter.
*/
- if (unlikely(local_read(&cpu_buffer->commits) != commits) &&
- !local_read(&cpu_buffer->committing)) {
+ if (unlikely(cpu_buffer->commits != commits) &&
+ !cpu_buffer->committing) {
local_inc(&cpu_buffer->committing);
goto again;
}
@@ -2415,7 +2415,7 @@ void ring_buffer_discard_commit(struct r
* committed yet. Thus we can assume that preemption
* is still disabled.
*/
- RB_WARN_ON(buffer, !local_read(&cpu_buffer->committing));
+ RB_WARN_ON(buffer, !cpu_buffer->committing);
rb_decrement_entry(cpu_buffer, event);
if (rb_try_to_discard(cpu_buffer, event))
@@ -2604,7 +2604,7 @@ unsigned long ring_buffer_entries_cpu(st
return 0;
cpu_buffer = buffer->buffers[cpu];
- ret = (local_read(&cpu_buffer->entries) - local_read(&cpu_buffer->overrun))
+ ret = cpu_buffer->entries - cpu_buffer->overrun
- cpu_buffer->read;
return ret;
@@ -2625,7 +2625,7 @@ unsigned long ring_buffer_overrun_cpu(st
return 0;
cpu_buffer = buffer->buffers[cpu];
- ret = local_read(&cpu_buffer->overrun);
+ ret = cpu_buffer->overrun;
return ret;
}
@@ -2646,7 +2646,7 @@ ring_buffer_commit_overrun_cpu(struct ri
return 0;
cpu_buffer = buffer->buffers[cpu];
- ret = local_read(&cpu_buffer->commit_overrun);
+ ret = cpu_buffer->commit_overrun;
return ret;
}
@@ -2668,8 +2668,8 @@ unsigned long ring_buffer_entries(struct
/* if you care about this being correct, lock the buffer */
for_each_buffer_cpu(buffer, cpu) {
cpu_buffer = buffer->buffers[cpu];
- entries += (local_read(&cpu_buffer->entries) -
- local_read(&cpu_buffer->overrun)) - cpu_buffer->read;
+ entries += cpu_buffer->entries -
+ cpu_buffer->overrun - cpu_buffer->read;
}
return entries;
@@ -2692,7 +2692,7 @@ unsigned long ring_buffer_overruns(struc
/* if you care about this being correct, lock the buffer */
for_each_buffer_cpu(buffer, cpu) {
cpu_buffer = buffer->buffers[cpu];
- overruns += local_read(&cpu_buffer->overrun);
+ overruns += cpu_buffer->overrun;
}
return overruns;
@@ -2861,9 +2861,9 @@ rb_get_reader_page(struct ring_buffer_pe
/*
* Reset the reader page to size zero.
*/
- local_set(&cpu_buffer->reader_page->write, 0);
- local_set(&cpu_buffer->reader_page->entries, 0);
- local_set(&cpu_buffer->reader_page->page->commit, 0);
+ cpu_buffer->reader_page->write = 0;
+ cpu_buffer->reader_page->entries = 0;
+ cpu_buffer->reader_page->page->commit = 0;
spin:
/*
@@ -3354,9 +3354,9 @@ rb_reset_cpu(struct ring_buffer_per_cpu
cpu_buffer->head_page
= list_entry(cpu_buffer->pages, struct buffer_page, list);
- local_set(&cpu_buffer->head_page->write, 0);
- local_set(&cpu_buffer->head_page->entries, 0);
- local_set(&cpu_buffer->head_page->page->commit, 0);
+ cpu_buffer->head_page->write = 0;
+ cpu_buffer->head_page->entries = 0;
+ cpu_buffer->head_page->page->commit = 0;
cpu_buffer->head_page->read = 0;
@@ -3364,16 +3364,16 @@ rb_reset_cpu(struct ring_buffer_per_cpu
cpu_buffer->commit_page = cpu_buffer->head_page;
INIT_LIST_HEAD(&cpu_buffer->reader_page->list);
- local_set(&cpu_buffer->reader_page->write, 0);
- local_set(&cpu_buffer->reader_page->entries, 0);
- local_set(&cpu_buffer->reader_page->page->commit, 0);
+ cpu_buffer->reader_page->write = 0;
+ cpu_buffer->reader_page->entries = 0;
+ cpu_buffer->reader_page->page->commit = 0;
cpu_buffer->reader_page->read = 0;
- local_set(&cpu_buffer->commit_overrun, 0);
- local_set(&cpu_buffer->overrun, 0);
- local_set(&cpu_buffer->entries, 0);
- local_set(&cpu_buffer->committing, 0);
- local_set(&cpu_buffer->commits, 0);
+ cpu_buffer->commit_overrun = 0;
+ cpu_buffer->overrun = 0;
+ cpu_buffer->entries = 0;
+ cpu_buffer->committing = 0;
+ cpu_buffer->commits = 0;
cpu_buffer->read = 0;
cpu_buffer->write_stamp = 0;
@@ -3399,7 +3399,7 @@ void ring_buffer_reset_cpu(struct ring_b
spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
- if (RB_WARN_ON(cpu_buffer, local_read(&cpu_buffer->committing)))
+ if (RB_WARN_ON(cpu_buffer, cpu_buffer->committing))
goto out;
arch_spin_lock(&cpu_buffer->lock);
@@ -3547,9 +3547,9 @@ int ring_buffer_swap_cpu(struct ring_buf
atomic_inc(&cpu_buffer_b->record_disabled);
ret = -EBUSY;
- if (local_read(&cpu_buffer_a->committing))
+ if (cpu_buffer_a->committing)
goto out_dec;
- if (local_read(&cpu_buffer_b->committing))
+ if (cpu_buffer_b->committing)
goto out_dec;
buffer_a->buffers[cpu] = cpu_buffer_b;
@@ -3733,7 +3733,7 @@ int ring_buffer_read_page(struct ring_bu
} while (len > size);
/* update bpage */
- local_set(&bpage->commit, pos);
+ bpage->commit = pos;
bpage->time_stamp = save_timestamp;
/* we copied everything to the beginning */
@@ -3746,8 +3746,8 @@ int ring_buffer_read_page(struct ring_bu
rb_init_page(bpage);
bpage = reader->page;
reader->page = *data_page;
- local_set(&reader->write, 0);
- local_set(&reader->entries, 0);
+ reader->write = 0;
+ reader->entries = 0;
reader->read = 0;
*data_page = bpage;
}
Index: linux-2.6/kernel/trace/ring_buffer_benchmark.c
===================================================================
--- linux-2.6.orig/kernel/trace/ring_buffer_benchmark.c 2010-01-07 16:09:45.000000000 -0600
+++ linux-2.6/kernel/trace/ring_buffer_benchmark.c 2010-01-07 16:12:46.000000000 -0600
@@ -12,7 +12,7 @@
struct rb_page {
u64 ts;
- local_t commit;
+ long commit;
char data[4080];
};
@@ -113,7 +113,7 @@ static enum event_status read_page(int c
ret = ring_buffer_read_page(buffer, &bpage, PAGE_SIZE, cpu, 1);
if (ret >= 0) {
rpage = bpage;
- commit = local_read(&rpage->commit);
+ commit = rpage->commit;
for (i = 0; i < commit && !kill_test; i += inc) {
if (i >= (PAGE_SIZE - offsetof(struct rb_page, data))) {
Index: linux-2.6/arch/alpha/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/alpha/include/asm/local.h 2010-01-07 16:09:45.000000000 -0600
+++ linux-2.6/arch/alpha/include/asm/local.h 2010-01-07 16:25:53.000000000 -0600
@@ -1,23 +1,9 @@
#ifndef _ALPHA_LOCAL_H
#define _ALPHA_LOCAL_H
-#include <linux/percpu.h>
-#include <asm/atomic.h>
+#include <linux/types.h>
-typedef struct
-{
- atomic_long_t a;
-} local_t;
-
-#define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
-#define local_read(l) atomic_long_read(&(l)->a)
-#define local_set(l,i) atomic_long_set(&(l)->a, (i))
-#define local_inc(l) atomic_long_inc(&(l)->a)
-#define local_dec(l) atomic_long_dec(&(l)->a)
-#define local_add(i,l) atomic_long_add((i),(&(l)->a))
-#define local_sub(i,l) atomic_long_sub((i),(&(l)->a))
-
-static __inline__ long local_add_return(long i, local_t * l)
+static __inline__ long local_add_return(long i, long *l)
{
long temp, result;
__asm__ __volatile__(
@@ -29,12 +15,17 @@ static __inline__ long local_add_return(
".subsection 2\n"
"2: br 1b\n"
".previous"
- :"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
- :"Ir" (i), "m" (l->a.counter) : "memory");
+ :"=&r" (temp), "=m" (*l), "=&r" (result)
+ :"Ir" (i), "m" (*l) : "memory");
return result;
}
+#define local_inc(l) local_add_return(1, (l))
+#define local_dec(l) local_add_return(-1, (l))
+#define local_add(i,l) local_add_return((i),(l))
+#define local_sub(i,l) local_add_return(-(i),(l))
+
#define local_cmpxchg(l, o, n) \
- (cmpxchg_local(&((l)->a.counter), (o), (n)))
+ (cmpxchg_local((l), (o), (n)))
#endif /* _ALPHA_LOCAL_H */
Index: linux-2.6/arch/m32r/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/m32r/include/asm/local.h 2010-01-07 16:09:45.000000000 -0600
+++ linux-2.6/arch/m32r/include/asm/local.h 2010-01-07 16:25:54.000000000 -0600
@@ -15,37 +15,6 @@
#include <asm/system.h>
#include <asm/local.h>
-/*
- * Atomic operations that C can't guarantee us. Useful for
- * resource counting etc..
- */
-
-/*
- * Make sure gcc doesn't try to be clever and move things around
- * on us. We need to use _exactly_ the address the user gave us,
- * not some alias that contains the same information.
- */
-typedef struct { volatile int counter; } local_t;
-
-#define LOCAL_INIT(i) { (i) }
-
-/**
- * local_read - read local variable
- * @l: pointer of type local_t
- *
- * Atomically reads the value of @l.
- */
-#define local_read(l) ((l)->counter)
-
-/**
- * local_set - set local variable
- * @l: pointer of type local_t
- * @i: required value
- *
- * Atomically sets the value of @l to @i.
- */
-#define local_set(l, i) (((l)->counter) = (i))
-
/**
* local_add_return - add long to local variable and return it
* @i: long value to add
@@ -53,7 +22,7 @@ typedef struct { volatile int counter; }
*
* Atomically adds @i to @l and return (@i + @l).
*/
-static inline long local_add_return(long i, local_t *l)
+static inline long local_add_return(long i, long *l)
{
unsigned long flags;
long result;
@@ -66,7 +35,7 @@ static inline long local_add_return(long
"add %0, %2; \n\t"
"st %0, @%1; \n\t"
: "=&r" (result)
- : "r" (&l->counter), "r" (i)
+ : "r" (*l), "r" (i)
: "memory"
#ifdef CONFIG_CHIP_M32700_TS1
, "r4"
@@ -111,7 +80,7 @@ static inline long local_add_return(long
*/
#define local_dec(l) local_sub(1, (l))
-#define local_cmpxchg(l, o, n) (cmpxchg_local(&((l)->counter), (o), (n)))
+#define local_cmpxchg(l, o, n) (cmpxchg_local((l), (o), (n)))
static inline void local_clear_mask(unsigned long mask, local_t *addr)
{
Index: linux-2.6/arch/mips/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/mips/include/asm/local.h 2010-01-07 16:09:45.000000000 -0600
+++ linux-2.6/arch/mips/include/asm/local.h 2010-01-07 16:25:53.000000000 -0600
@@ -7,25 +7,7 @@
#include <asm/cmpxchg.h>
#include <asm/war.h>
-typedef struct
-{
- atomic_long_t a;
-} local_t;
-
-#define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
-
-#define local_read(l) atomic_long_read(&(l)->a)
-#define local_set(l, i) atomic_long_set(&(l)->a, (i))
-
-#define local_add(i, l) atomic_long_add((i), (&(l)->a))
-#define local_sub(i, l) atomic_long_sub((i), (&(l)->a))
-#define local_inc(l) atomic_long_inc(&(l)->a)
-#define local_dec(l) atomic_long_dec(&(l)->a)
-
-/*
- * Same as above, but return the result value
- */
-static __inline__ long local_add_return(long i, local_t * l)
+static __inline__ long local_add_return(long i, long * l)
{
unsigned long result;
@@ -40,8 +22,8 @@ static __inline__ long local_add_return(
" beqzl %0, 1b \n"
" addu %0, %1, %3 \n"
" .set mips0 \n"
- : "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
- : "Ir" (i), "m" (l->a.counter)
+ : "=&r" (result), "=&r" (temp), "=m" (*l)
+ : "Ir" (i), "m" (*l)
: "memory");
} else if (kernel_uses_llsc) {
unsigned long temp;
@@ -54,23 +36,28 @@ static __inline__ long local_add_return(
" beqz %0, 1b \n"
" addu %0, %1, %3 \n"
" .set mips0 \n"
- : "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
- : "Ir" (i), "m" (l->a.counter)
+ : "=&r" (result), "=&r" (temp), "=m" (*l)
+ : "Ir" (i), "m" (*l)
: "memory");
} else {
unsigned long flags;
local_irq_save(flags);
- result = l->a.counter;
+ result = *l;
result += i;
- l->a.counter = result;
+ *l = result;
local_irq_restore(flags);
}
return result;
}
+#define local_add(i, l) local_add_return((i), (l))
+#define local_sub(i, l) local_add_return(-(i), (l))
+#define local_inc(l) local_add_return(-1, (l))
+#define local_dec(l) local_add_return(-1, (l))
+
#define local_cmpxchg(l, o, n) \
- ((long)cmpxchg_local(&((l)->a.counter), (o), (n)))
+ ((long)cmpxchg_local((l), (o), (n)))
#endif /* _ARCH_MIPS_LOCAL_H */
--
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [RFC local_t removal V2 2/3] Remove local_t type from tree.
2010-01-07 22:35 ` [RFC local_t removal V2 2/3] Remove local_t type from tree Christoph Lameter
@ 2010-01-08 8:55 ` Arnd Bergmann
0 siblings, 0 replies; 5+ messages in thread
From: Arnd Bergmann @ 2010-01-08 8:55 UTC (permalink / raw)
To: Christoph Lameter
Cc: Mathieu Desnoyers, Tejun Heo, Mike Frysinger, linux-kernel
On Thursday 07 January 2010 23:35:26 Christoph Lameter wrote:
> -#define local_add_return(i, l) atomic_long_add_return((i), (&(l)->a))
> + local_irq_save(flags);
> + switch (size) {
> + case 1: r = (*((u8 *)ptr) += value);
> + break;
> + case 2: r = (*((u16 *)ptr) += value);
> + break;
> + case 4: r = (*((u32 *)ptr) += value);
> + break;
> + case 8: r = (*((u64 *)ptr) += value);
> + break;
> + }
> + local_irq_restore(flags);
> + return r;
> +}
This still misses 'volatile'.
Arnd
^ permalink raw reply [flat|nested] 5+ messages in thread
* [RFC local_t removal V2 3/3] Eliminate local_cmpxchg
2010-01-07 22:35 [RFC local_t removal V2 0/3] Remove local_t Christoph Lameter
2010-01-07 22:35 ` [RFC local_t removal V2 1/3] Remove unused local.h functions Christoph Lameter
2010-01-07 22:35 ` [RFC local_t removal V2 2/3] Remove local_t type from tree Christoph Lameter
@ 2010-01-07 22:35 ` Christoph Lameter
2 siblings, 0 replies; 5+ messages in thread
From: Christoph Lameter @ 2010-01-07 22:35 UTC (permalink / raw)
To: Mathieu Desnoyers; +Cc: Tejun Heo, Mike Frysinger, Arnd Bergmann, linux-kernel
[-- Attachment #1: remove_cmpxchg_local --]
[-- Type: text/plain, Size: 4822 bytes --]
cmpxchg_local is the same as local_cmpxchg.
Keep cmpxchg_local and change the 3 occurrences of local_cmpxchg to cmpxchg_local.
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
---
arch/alpha/include/asm/local.h | 3 ---
arch/m32r/include/asm/local.h | 2 --
arch/mips/include/asm/local.h | 3 ---
arch/powerpc/include/asm/local.h | 3 ---
arch/x86/include/asm/local.h | 3 ---
include/asm-generic/local.h | 2 --
kernel/trace/ring_buffer.c | 6 +++---
7 files changed, 3 insertions(+), 19 deletions(-)
Index: linux-2.6/arch/alpha/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/alpha/include/asm/local.h 2010-01-07 15:27:50.000000000 -0600
+++ linux-2.6/arch/alpha/include/asm/local.h 2010-01-07 15:27:56.000000000 -0600
@@ -25,7 +25,4 @@ static __inline__ long local_add_return(
#define local_add(i,l) local_add_return((i),(l))
#define local_sub(i,l) local_add_return(-(i),(l))
-#define local_cmpxchg(l, o, n) \
- (cmpxchg_local((l), (o), (n)))
-
#endif /* _ALPHA_LOCAL_H */
Index: linux-2.6/arch/m32r/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/m32r/include/asm/local.h 2010-01-07 15:27:33.000000000 -0600
+++ linux-2.6/arch/m32r/include/asm/local.h 2010-01-07 15:27:39.000000000 -0600
@@ -80,8 +80,6 @@ static inline long local_add_return(long
*/
#define local_dec(l) ((void)local_add_return(-1, (l))
-#define local_cmpxchg(l, o, n) (cmpxchg_local((l), (o), (n)))
-
static inline void local_clear_mask(unsigned long mask, local_t *addr)
{
unsigned long flags;
Index: linux-2.6/arch/mips/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/mips/include/asm/local.h 2010-01-07 15:27:21.000000000 -0600
+++ linux-2.6/arch/mips/include/asm/local.h 2010-01-07 15:27:27.000000000 -0600
@@ -57,7 +57,4 @@ static __inline__ long local_add_return(
#define local_inc(l) local_add_return(-1, (l))
#define local_dec(l) local_add_return(-1, (l))
-#define local_cmpxchg(l, o, n) \
- ((long)cmpxchg_local((l), (o), (n)))
-
#endif /* _ARCH_MIPS_LOCAL_H */
Index: linux-2.6/arch/powerpc/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/powerpc/include/asm/local.h 2010-01-07 15:27:00.000000000 -0600
+++ linux-2.6/arch/powerpc/include/asm/local.h 2010-01-07 15:27:04.000000000 -0600
@@ -26,7 +26,4 @@ static __inline__ long local_add_return(
#define local_inc(l) local_add_return(-1, (l))
#define local_dec(l) local_add_return(-1, (l))
-#define local_cmpxchg(l, o, n) \
- (cmpxchg_local((l), (o), (n)))
-
#endif /* _ARCH_POWERPC_LOCAL_H */
Index: linux-2.6/arch/x86/include/asm/local.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/local.h 2010-01-07 15:26:36.000000000 -0600
+++ linux-2.6/arch/x86/include/asm/local.h 2010-01-07 15:26:45.000000000 -0600
@@ -65,7 +65,4 @@ no_xadd: /* Legacy 386 processor */
#endif
}
-#define local_cmpxchg(l, o, n) \
- (cmpxchg_local((l), (o), (n)))
-
#endif /* _ASM_X86_LOCAL_H */
Index: linux-2.6/include/asm-generic/local.h
===================================================================
--- linux-2.6.orig/include/asm-generic/local.h 2010-01-07 15:28:09.000000000 -0600
+++ linux-2.6/include/asm-generic/local.h 2010-01-07 15:28:39.000000000 -0600
@@ -53,6 +53,4 @@ static inline unsigned long __add_return
#define local_add(i,l) local_add_return((i), (l))
#define local_sub(i,l) local_add_return(-(i), (l))
-#define local_cmpxchg(l, o, n) cmpxchg_local((l), (o), (n))
-
#endif /* _ASM_GENERIC_LOCAL_i */
Index: linux-2.6/kernel/trace/ring_buffer.c
===================================================================
--- linux-2.6.orig/kernel/trace/ring_buffer.c 2010-01-07 15:25:38.000000000 -0600
+++ linux-2.6/kernel/trace/ring_buffer.c 2010-01-07 15:26:14.000000000 -0600
@@ -853,8 +853,8 @@ static int rb_tail_page_update(struct ri
* cmpxchg to only update if an interrupt did not already
* do it for us. If the cmpxchg fails, we don't care.
*/
- (void)local_cmpxchg(&next_page->write, old_write, val);
- (void)local_cmpxchg(&next_page->entries, old_entries, eval);
+ (void)cmpxchg_local(&next_page->write, old_write, val);
+ (void)cmpxchg_local(&next_page->entries, old_entries, eval);
/*
* No need to worry about races with clearing out the commit.
@@ -1952,7 +1952,7 @@ rb_try_to_discard(struct ring_buffer_per
*/
old_index += write_mask;
new_index += write_mask;
- index = local_cmpxchg(&bpage->write, old_index, new_index);
+ index = cmpxchg_local(&bpage->write, old_index, new_index);
if (index == old_index)
return 1;
}
--
^ permalink raw reply [flat|nested] 5+ messages in thread