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-rw-r--r--arch/x86/include/asm/asm.h2
-rw-r--r--arch/x86/include/asm/rwlock.h43
-rw-r--r--arch/x86/include/asm/spinlock.h37
-rw-r--r--arch/x86/include/asm/spinlock_types.h6
-rw-r--r--arch/x86/lib/rwlock.S12
-rw-r--r--arch/x86/lib/thunk_64.S1
6 files changed, 73 insertions, 28 deletions
diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
index 5890beb021c4..9412d6558c88 100644
--- a/arch/x86/include/asm/asm.h
+++ b/arch/x86/include/asm/asm.h
@@ -3,9 +3,11 @@
#ifdef __ASSEMBLY__
# define __ASM_FORM(x) x
+# define __ASM_FORM_COMMA(x) x,
# define __ASM_EX_SEC .section __ex_table, "a"
#else
# define __ASM_FORM(x) " " #x " "
+# define __ASM_FORM_COMMA(x) " " #x ","
# define __ASM_EX_SEC " .section __ex_table,\"a\"\n"
#endif
diff --git a/arch/x86/include/asm/rwlock.h b/arch/x86/include/asm/rwlock.h
index 6a8c0d645108..a5370a03d90c 100644
--- a/arch/x86/include/asm/rwlock.h
+++ b/arch/x86/include/asm/rwlock.h
@@ -1,7 +1,48 @@
#ifndef _ASM_X86_RWLOCK_H
#define _ASM_X86_RWLOCK_H
-#define RW_LOCK_BIAS 0x01000000
+#include <asm/asm.h>
+
+#if CONFIG_NR_CPUS <= 2048
+
+#ifndef __ASSEMBLY__
+typedef union {
+ s32 lock;
+ s32 write;
+} arch_rwlock_t;
+#endif
+
+#define RW_LOCK_BIAS 0x00100000
+#define READ_LOCK_SIZE(insn) __ASM_FORM(insn##l)
+#define READ_LOCK_ATOMIC(n) atomic_##n
+#define WRITE_LOCK_ADD(n) __ASM_FORM_COMMA(addl n)
+#define WRITE_LOCK_SUB(n) __ASM_FORM_COMMA(subl n)
+#define WRITE_LOCK_CMP RW_LOCK_BIAS
+
+#else /* CONFIG_NR_CPUS > 2048 */
+
+#include <linux/const.h>
+
+#ifndef __ASSEMBLY__
+typedef union {
+ s64 lock;
+ struct {
+ u32 read;
+ s32 write;
+ };
+} arch_rwlock_t;
+#endif
+
+#define RW_LOCK_BIAS (_AC(1,L) << 32)
+#define READ_LOCK_SIZE(insn) __ASM_FORM(insn##q)
+#define READ_LOCK_ATOMIC(n) atomic64_##n
+#define WRITE_LOCK_ADD(n) __ASM_FORM(incl)
+#define WRITE_LOCK_SUB(n) __ASM_FORM(decl)
+#define WRITE_LOCK_CMP 1
+
+#endif /* CONFIG_NR_CPUS */
+
+#define __ARCH_RW_LOCK_UNLOCKED { RW_LOCK_BIAS }
/* Actual code is in asm/spinlock.h or in arch/x86/lib/rwlock.S */
diff --git a/arch/x86/include/asm/spinlock.h b/arch/x86/include/asm/spinlock.h
index 3089f70c0c52..e9e51f710e6c 100644
--- a/arch/x86/include/asm/spinlock.h
+++ b/arch/x86/include/asm/spinlock.h
@@ -2,7 +2,6 @@
#define _ASM_X86_SPINLOCK_H
#include <asm/atomic.h>
-#include <asm/rwlock.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <linux/compiler.h>
@@ -234,7 +233,7 @@ static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
*/
static inline int arch_read_can_lock(arch_rwlock_t *lock)
{
- return (int)(lock)->lock > 0;
+ return lock->lock > 0;
}
/**
@@ -243,12 +242,12 @@ static inline int arch_read_can_lock(arch_rwlock_t *lock)
*/
static inline int arch_write_can_lock(arch_rwlock_t *lock)
{
- return (lock)->lock == RW_LOCK_BIAS;
+ return lock->write == WRITE_LOCK_CMP;
}
static inline void arch_read_lock(arch_rwlock_t *rw)
{
- asm volatile(LOCK_PREFIX " subl $1,(%0)\n\t"
+ asm volatile(LOCK_PREFIX READ_LOCK_SIZE(dec) " (%0)\n\t"
"jns 1f\n"
"call __read_lock_failed\n\t"
"1:\n"
@@ -257,47 +256,55 @@ static inline void arch_read_lock(arch_rwlock_t *rw)
static inline void arch_write_lock(arch_rwlock_t *rw)
{
- asm volatile(LOCK_PREFIX " subl %1,(%0)\n\t"
+ asm volatile(LOCK_PREFIX WRITE_LOCK_SUB(%1) "(%0)\n\t"
"jz 1f\n"
"call __write_lock_failed\n\t"
"1:\n"
- ::LOCK_PTR_REG (rw), "i" (RW_LOCK_BIAS) : "memory");
+ ::LOCK_PTR_REG (&rw->write), "i" (RW_LOCK_BIAS)
+ : "memory");
}
static inline int arch_read_trylock(arch_rwlock_t *lock)
{
- atomic_t *count = (atomic_t *)lock;
+ READ_LOCK_ATOMIC(t) *count = (READ_LOCK_ATOMIC(t) *)lock;
- if (atomic_dec_return(count) >= 0)
+ if (READ_LOCK_ATOMIC(dec_return)(count) >= 0)
return 1;
- atomic_inc(count);
+ READ_LOCK_ATOMIC(inc)(count);
return 0;
}
static inline int arch_write_trylock(arch_rwlock_t *lock)
{
- atomic_t *count = (atomic_t *)lock;
+ atomic_t *count = (atomic_t *)&lock->write;
- if (atomic_sub_and_test(RW_LOCK_BIAS, count))
+ if (atomic_sub_and_test(WRITE_LOCK_CMP, count))
return 1;
- atomic_add(RW_LOCK_BIAS, count);
+ atomic_add(WRITE_LOCK_CMP, count);
return 0;
}
static inline void arch_read_unlock(arch_rwlock_t *rw)
{
- asm volatile(LOCK_PREFIX "incl %0" :"+m" (rw->lock) : : "memory");
+ asm volatile(LOCK_PREFIX READ_LOCK_SIZE(inc) " %0"
+ :"+m" (rw->lock) : : "memory");
}
static inline void arch_write_unlock(arch_rwlock_t *rw)
{
- asm volatile(LOCK_PREFIX "addl %1, %0"
- : "+m" (rw->lock) : "i" (RW_LOCK_BIAS) : "memory");
+ asm volatile(LOCK_PREFIX WRITE_LOCK_ADD(%1) "%0"
+ : "+m" (rw->write) : "i" (RW_LOCK_BIAS) : "memory");
}
#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)
#define arch_write_lock_flags(lock, flags) arch_write_lock(lock)
+#undef READ_LOCK_SIZE
+#undef READ_LOCK_ATOMIC
+#undef WRITE_LOCK_ADD
+#undef WRITE_LOCK_SUB
+#undef WRITE_LOCK_CMP
+
#define arch_spin_relax(lock) cpu_relax()
#define arch_read_relax(lock) cpu_relax()
#define arch_write_relax(lock) cpu_relax()
diff --git a/arch/x86/include/asm/spinlock_types.h b/arch/x86/include/asm/spinlock_types.h
index dcb48b2edc11..7c7a486fcb68 100644
--- a/arch/x86/include/asm/spinlock_types.h
+++ b/arch/x86/include/asm/spinlock_types.h
@@ -11,10 +11,6 @@ typedef struct arch_spinlock {
#define __ARCH_SPIN_LOCK_UNLOCKED { 0 }
-typedef struct {
- unsigned int lock;
-} arch_rwlock_t;
-
-#define __ARCH_RW_LOCK_UNLOCKED { RW_LOCK_BIAS }
+#include <asm/rwlock.h>
#endif /* _ASM_X86_SPINLOCK_TYPES_H */
diff --git a/arch/x86/lib/rwlock.S b/arch/x86/lib/rwlock.S
index fca17829caa8..1cad22139c88 100644
--- a/arch/x86/lib/rwlock.S
+++ b/arch/x86/lib/rwlock.S
@@ -15,12 +15,12 @@ ENTRY(__write_lock_failed)
CFI_STARTPROC
FRAME
0: LOCK_PREFIX
- addl $RW_LOCK_BIAS, (%__lock_ptr)
+ WRITE_LOCK_ADD($RW_LOCK_BIAS) (%__lock_ptr)
1: rep; nop
- cmpl $RW_LOCK_BIAS, (%__lock_ptr)
+ cmpl $WRITE_LOCK_CMP, (%__lock_ptr)
jne 1b
LOCK_PREFIX
- subl $RW_LOCK_BIAS, (%__lock_ptr)
+ WRITE_LOCK_SUB($RW_LOCK_BIAS) (%__lock_ptr)
jnz 0b
ENDFRAME
ret
@@ -31,12 +31,12 @@ ENTRY(__read_lock_failed)
CFI_STARTPROC
FRAME
0: LOCK_PREFIX
- incl (%__lock_ptr)
+ READ_LOCK_SIZE(inc) (%__lock_ptr)
1: rep; nop
- cmpl $1, (%__lock_ptr)
+ READ_LOCK_SIZE(cmp) $1, (%__lock_ptr)
js 1b
LOCK_PREFIX
- decl (%__lock_ptr)
+ READ_LOCK_SIZE(dec) (%__lock_ptr)
js 0b
ENDFRAME
ret
diff --git a/arch/x86/lib/thunk_64.S b/arch/x86/lib/thunk_64.S
index d5b088b3ab81..a63efd6bb6a5 100644
--- a/arch/x86/lib/thunk_64.S
+++ b/arch/x86/lib/thunk_64.S
@@ -8,7 +8,6 @@
#include <linux/linkage.h>
#include <asm/dwarf2.h>
#include <asm/calling.h>
-#include <asm/rwlock.h>
/* rdi: arg1 ... normal C conventions. rax is saved/restored. */
.macro THUNK name, func, put_ret_addr_in_rdi=0
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