locking/arch, x86: Add __down_read_killable()

[mirror_ubuntu-bionic-kernel.git] / arch / x86 / include / asm / rwsem.h

diff --git a/arch/x86/include/asm/rwsem.h b/arch/x86/include/asm/rwsem.h
index 7116b7931c7b807766fef6d820ec929da43940c7..1e51195c0b63fc66db39659cab67db28918eae51 100644 (file)
--- a/arch/x86/include/asm/rwsem.h
+++ b/arch/x86/include/asm/rwsem.h
@@ -60,18 +60,33 @@
 /*
  * lock for reading
  */
+#define ____down_read(sem, slow_path)                                  \
+({                                                                     \
+       struct rw_semaphore* ret;                                       \
+       asm volatile("# beginning down_read\n\t"                        \
+                    LOCK_PREFIX _ASM_INC "(%[sem])\n\t"                \
+                    /* adds 0x00000001 */                              \
+                    "  jns        1f\n"                                \
+                    "  call " slow_path "\n"                           \
+                    "1:\n\t"                                           \
+                    "# ending down_read\n\t"                           \
+                    : "+m" (sem->count), "=a" (ret),                   \
+                       ASM_CALL_CONSTRAINT                             \
+                    : [sem] "a" (sem)                                  \
+                    : "memory", "cc");                                 \
+       ret;                                                            \
+})
+
 static inline void __down_read(struct rw_semaphore *sem)
 {
-       asm volatile("# beginning down_read\n\t"
-                    LOCK_PREFIX _ASM_INC "(%1)\n\t"
-                    /* adds 0x00000001 */
-                    "  jns        1f\n"
-                    "  call call_rwsem_down_read_failed\n"
-                    "1:\n\t"
-                    "# ending down_read\n\t"
-                    : "+m" (sem->count)
-                    : "a" (sem)
-                    : "memory", "cc");
+       ____down_read(sem, "call_rwsem_down_read_failed");
+}
+
+static inline int __down_read_killable(struct rw_semaphore *sem)
+{
+       if (IS_ERR(____down_read(sem, "call_rwsem_down_read_failed_killable")))
+               return -EINTR;
+       return 0;
 }
 
 /*
@@ -81,17 +96,18 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem)
 {
        long result, tmp;
        asm volatile("# beginning __down_read_trylock\n\t"
-                    "  mov          %0,%1\n\t"
+                    "  mov          %[count],%[result]\n\t"
                     "1:\n\t"
-                    "  mov          %1,%2\n\t"
-                    "  add          %3,%2\n\t"
+                    "  mov          %[result],%[tmp]\n\t"
+                    "  add          %[inc],%[tmp]\n\t"
                     "  jle          2f\n\t"
-                    LOCK_PREFIX "  cmpxchg  %2,%0\n\t"
+                    LOCK_PREFIX "  cmpxchg  %[tmp],%[count]\n\t"
                     "  jnz          1b\n\t"
                     "2:\n\t"
                     "# ending __down_read_trylock\n\t"
-                    : "+m" (sem->count), "=&a" (result), "=&r" (tmp)
-                    : "i" (RWSEM_ACTIVE_READ_BIAS)
+                    : [count] "+m" (sem->count), [result] "=&a" (result),
+                      [tmp] "=&r" (tmp)
+                    : [inc] "i" (RWSEM_ACTIVE_READ_BIAS)
                     : "memory", "cc");
        return result >= 0;
 }
@@ -105,7 +121,7 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem)
        struct rw_semaphore* ret;                       \
                                                        \
        asm volatile("# beginning down_write\n\t"       \
-                    LOCK_PREFIX "  xadd      %1,(%4)\n\t"      \
+                    LOCK_PREFIX "  xadd      %[tmp],(%[sem])\n\t"      \
                     /* adds 0xffff0001, returns the old value */ \
                     "  test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t" \
                     /* was the active mask 0 before? */\
@@ -113,9 +129,9 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem)
                     "  call " slow_path "\n"           \
                     "1:\n"                             \
                     "# ending down_write"              \
-                    : "+m" (sem->count), "=d" (tmp),   \
+                    : "+m" (sem->count), [tmp] "=d" (tmp),     \
                       "=a" (ret), ASM_CALL_CONSTRAINT  \
-                    : "a" (sem), "1" (RWSEM_ACTIVE_WRITE_BIAS) \
+                    : [sem] "a" (sem), "[tmp]" (RWSEM_ACTIVE_WRITE_BIAS) \
                     : "memory", "cc");                 \
        ret;                                            \
 })
@@ -141,21 +157,21 @@ static inline bool __down_write_trylock(struct rw_semaphore *sem)
        bool result;
        long tmp0, tmp1;
        asm volatile("# beginning __down_write_trylock\n\t"
-                    "  mov          %0,%1\n\t"
+                    "  mov          %[count],%[tmp0]\n\t"
                     "1:\n\t"
                     "  test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t"
                     /* was the active mask 0 before? */
                     "  jnz          2f\n\t"
-                    "  mov          %1,%2\n\t"
-                    "  add          %4,%2\n\t"
-                    LOCK_PREFIX "  cmpxchg  %2,%0\n\t"
+                    "  mov          %[tmp0],%[tmp1]\n\t"
+                    "  add          %[inc],%[tmp1]\n\t"
+                    LOCK_PREFIX "  cmpxchg  %[tmp1],%[count]\n\t"
                     "  jnz          1b\n\t"
                     "2:\n\t"
                     CC_SET(e)
                     "# ending __down_write_trylock\n\t"
-                    : "+m" (sem->count), "=&a" (tmp0), "=&r" (tmp1),
-                      CC_OUT(e) (result)
-                    : "er" (RWSEM_ACTIVE_WRITE_BIAS)
+                    : [count] "+m" (sem->count), [tmp0] "=&a" (tmp0),
+                      [tmp1] "=&r" (tmp1), CC_OUT(e) (result)
+                    : [inc] "er" (RWSEM_ACTIVE_WRITE_BIAS)
                     : "memory");
        return result;
 }
@@ -167,14 +183,14 @@ static inline void __up_read(struct rw_semaphore *sem)
 {
        long tmp;
        asm volatile("# beginning __up_read\n\t"
-                    LOCK_PREFIX "  xadd      %1,(%2)\n\t"
+                    LOCK_PREFIX "  xadd      %[tmp],(%[sem])\n\t"
                     /* subtracts 1, returns the old value */
                     "  jns        1f\n\t"
                     "  call call_rwsem_wake\n" /* expects old value in %edx */
                     "1:\n"
                     "# ending __up_read\n"
-                    : "+m" (sem->count), "=d" (tmp)
-                    : "a" (sem), "1" (-RWSEM_ACTIVE_READ_BIAS)
+                    : "+m" (sem->count), [tmp] "=d" (tmp)
+                    : [sem] "a" (sem), "[tmp]" (-RWSEM_ACTIVE_READ_BIAS)
                     : "memory", "cc");
 }
 
@@ -185,14 +201,14 @@ static inline void __up_write(struct rw_semaphore *sem)
 {
        long tmp;
        asm volatile("# beginning __up_write\n\t"
-                    LOCK_PREFIX "  xadd      %1,(%2)\n\t"
+                    LOCK_PREFIX "  xadd      %[tmp],(%[sem])\n\t"
                     /* subtracts 0xffff0001, returns the old value */
                     "  jns        1f\n\t"
                     "  call call_rwsem_wake\n" /* expects old value in %edx */
                     "1:\n\t"
                     "# ending __up_write\n"
-                    : "+m" (sem->count), "=d" (tmp)
-                    : "a" (sem), "1" (-RWSEM_ACTIVE_WRITE_BIAS)
+                    : "+m" (sem->count), [tmp] "=d" (tmp)
+                    : [sem] "a" (sem), "[tmp]" (-RWSEM_ACTIVE_WRITE_BIAS)
                     : "memory", "cc");
 }
 
@@ -202,7 +218,7 @@ static inline void __up_write(struct rw_semaphore *sem)
 static inline void __downgrade_write(struct rw_semaphore *sem)
 {
        asm volatile("# beginning __downgrade_write\n\t"
-                    LOCK_PREFIX _ASM_ADD "%2,(%1)\n\t"
+                    LOCK_PREFIX _ASM_ADD "%[inc],(%[sem])\n\t"
                     /*
                      * transitions 0xZZZZ0001 -> 0xYYYY0001 (i386)
                      *     0xZZZZZZZZ00000001 -> 0xYYYYYYYY00000001 (x86_64)
@@ -212,7 +228,7 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
                     "1:\n\t"
                     "# ending __downgrade_write\n"
                     : "+m" (sem->count)
-                    : "a" (sem), "er" (-RWSEM_WAITING_BIAS)
+                    : [sem] "a" (sem), [inc] "er" (-RWSEM_WAITING_BIAS)
                     : "memory", "cc");
 }