atomic: Add testandclear on i386/amd64
Reviewed by: kib Sponsored by: Microsoft OSTC Differential Revision: https://reviews.freebsd.org/D6381
This commit is contained in:
Sepherosa Ziehau
parent
95c6a8211c
commit
dfdc9a05c6
@ -23,7 +23,7 @@
|
||||
.\"
|
||||
.\" $FreeBSD$
|
||||
.\"
|
||||
.Dd August 14, 2015
|
||||
.Dd May 12, 2016
|
||||
.Dt ATOMIC 9
|
||||
.Os
|
||||
.Sh NAME
|
||||
@ -65,6 +65,8 @@
|
||||
.Ft <type>
|
||||
.Fn atomic_swap_<type> "volatile <type> *p" "<type> v"
|
||||
.Ft int
|
||||
.Fn atomic_testandclear_<type> "volatile <type> *p" "u_int v"
|
||||
.Ft int
|
||||
.Fn atomic_testandset_<type> "volatile <type> *p" "u_int v"
|
||||
.Sh DESCRIPTION
|
||||
Each of the atomic operations is guaranteed to be atomic across multiple
|
||||
@ -309,6 +311,15 @@ and
|
||||
.Dq Li 16
|
||||
and do not have any variants with memory barriers at this time.
|
||||
.Bl -hang
|
||||
.It Fn atomic_testandclear p v
|
||||
.Bd -literal -compact
|
||||
bit = 1 << (v % (sizeof(*p) * NBBY));
|
||||
tmp = (*p & bit) != 0;
|
||||
*p &= ~bit;
|
||||
return (tmp);
|
||||
.Ed
|
||||
.El
|
||||
.Bl -hang
|
||||
.It Fn atomic_testandset p v
|
||||
.Bd -literal -compact
|
||||
bit = 1 << (v % (sizeof(*p) * NBBY));
|
||||
@ -320,6 +331,8 @@ return (tmp);
|
||||
.Pp
|
||||
The
|
||||
.Fn atomic_testandset
|
||||
and
|
||||
.Fn atomic_testandclear
|
||||
functions are only implemented for the types
|
||||
.Dq Li int ,
|
||||
.Dq Li long
|
||||
@ -348,6 +361,8 @@ and
|
||||
functions return the value at the specified address.
|
||||
The
|
||||
.Fn atomic_testandset
|
||||
and
|
||||
.Fn atomic_testandclear
|
||||
function returns the result of the test operation.
|
||||
.Sh EXAMPLES
|
||||
This example uses the
|
||||
@ -425,3 +440,6 @@ and
|
||||
.Fn atomic_testandset
|
||||
operations were added in
|
||||
.Fx 10.0 .
|
||||
.Fn atomic_testandclear
|
||||
operation was added in
|
||||
.Fx 11.0 .
|
||||
|
||||
@ -103,6 +103,8 @@ u_int atomic_fetchadd_int(volatile u_int *p, u_int v);
|
||||
u_long atomic_fetchadd_long(volatile u_long *p, u_long v);
|
||||
int atomic_testandset_int(volatile u_int *p, u_int v);
|
||||
int atomic_testandset_long(volatile u_long *p, u_int v);
|
||||
int atomic_testandclear_int(volatile u_int *p, u_int v);
|
||||
int atomic_testandclear_long(volatile u_long *p, u_int v);
|
||||
void atomic_thread_fence_acq(void);
|
||||
void atomic_thread_fence_acq_rel(void);
|
||||
void atomic_thread_fence_rel(void);
|
||||
@ -264,6 +266,40 @@ atomic_testandset_long(volatile u_long *p, u_int v)
|
||||
return (res);
|
||||
}
|
||||
|
||||
static __inline int
|
||||
atomic_testandclear_int(volatile u_int *p, u_int v)
|
||||
{
|
||||
u_char res;
|
||||
|
||||
__asm __volatile(
|
||||
" " MPLOCKED " "
|
||||
" btrl %2,%1 ; "
|
||||
" setc %0 ; "
|
||||
"# atomic_testandclear_int"
|
||||
: "=q" (res), /* 0 */
|
||||
"+m" (*p) /* 1 */
|
||||
: "Ir" (v & 0x1f) /* 2 */
|
||||
: "cc");
|
||||
return (res);
|
||||
}
|
||||
|
||||
static __inline int
|
||||
atomic_testandclear_long(volatile u_long *p, u_int v)
|
||||
{
|
||||
u_char res;
|
||||
|
||||
__asm __volatile(
|
||||
" " MPLOCKED " "
|
||||
" btrq %2,%1 ; "
|
||||
" setc %0 ; "
|
||||
"# atomic_testandclear_long"
|
||||
: "=q" (res), /* 0 */
|
||||
"+m" (*p) /* 1 */
|
||||
: "Jr" ((u_long)(v & 0x3f)) /* 2 */
|
||||
: "cc");
|
||||
return (res);
|
||||
}
|
||||
|
||||
/*
|
||||
* We assume that a = b will do atomic loads and stores. Due to the
|
||||
* IA32 memory model, a simple store guarantees release semantics.
|
||||
@ -537,6 +573,7 @@ u_long atomic_swap_long(volatile u_long *p, u_long v);
|
||||
#define atomic_readandclear_32 atomic_readandclear_int
|
||||
#define atomic_fetchadd_32 atomic_fetchadd_int
|
||||
#define atomic_testandset_32 atomic_testandset_int
|
||||
#define atomic_testandclear_32 atomic_testandclear_int
|
||||
|
||||
/* Operations on 64-bit quad words. */
|
||||
#define atomic_set_64 atomic_set_long
|
||||
@ -560,6 +597,7 @@ u_long atomic_swap_long(volatile u_long *p, u_long v);
|
||||
#define atomic_readandclear_64 atomic_readandclear_long
|
||||
#define atomic_fetchadd_64 atomic_fetchadd_long
|
||||
#define atomic_testandset_64 atomic_testandset_long
|
||||
#define atomic_testandclear_64 atomic_testandclear_long
|
||||
|
||||
/* Operations on pointers. */
|
||||
#define atomic_set_ptr atomic_set_long
|
||||
|
||||
@ -108,6 +108,7 @@ void atomic_##NAME##_barr_##TYPE(volatile u_##TYPE *p, u_##TYPE v)
|
||||
int atomic_cmpset_int(volatile u_int *dst, u_int expect, u_int src);
|
||||
u_int atomic_fetchadd_int(volatile u_int *p, u_int v);
|
||||
int atomic_testandset_int(volatile u_int *p, u_int v);
|
||||
int atomic_testandclear_int(volatile u_int *p, u_int v);
|
||||
void atomic_thread_fence_acq(void);
|
||||
void atomic_thread_fence_acq_rel(void);
|
||||
void atomic_thread_fence_rel(void);
|
||||
@ -250,6 +251,23 @@ atomic_testandset_int(volatile u_int *p, u_int v)
|
||||
return (res);
|
||||
}
|
||||
|
||||
static __inline int
|
||||
atomic_testandclear_int(volatile u_int *p, u_int v)
|
||||
{
|
||||
u_char res;
|
||||
|
||||
__asm __volatile(
|
||||
" " MPLOCKED " "
|
||||
" btrl %2,%1 ; "
|
||||
" setc %0 ; "
|
||||
"# atomic_testandclear_int"
|
||||
: "=q" (res), /* 0 */
|
||||
"+m" (*p) /* 1 */
|
||||
: "Ir" (v & 0x1f) /* 2 */
|
||||
: "cc");
|
||||
return (res);
|
||||
}
|
||||
|
||||
/*
|
||||
* We assume that a = b will do atomic loads and stores. Due to the
|
||||
* IA32 memory model, a simple store guarantees release semantics.
|
||||
@ -602,6 +620,13 @@ atomic_testandset_long(volatile u_long *p, u_int v)
|
||||
return (atomic_testandset_int((volatile u_int *)p, v));
|
||||
}
|
||||
|
||||
static __inline int
|
||||
atomic_testandclear_long(volatile u_long *p, u_int v)
|
||||
{
|
||||
|
||||
return (atomic_testandclear_int((volatile u_int *)p, v));
|
||||
}
|
||||
|
||||
/* Read the current value and store a new value in the destination. */
|
||||
#ifdef __GNUCLIKE_ASM
|
||||
|
||||
@ -728,6 +753,7 @@ u_long atomic_swap_long(volatile u_long *p, u_long v);
|
||||
#define atomic_readandclear_32 atomic_readandclear_int
|
||||
#define atomic_fetchadd_32 atomic_fetchadd_int
|
||||
#define atomic_testandset_32 atomic_testandset_int
|
||||
#define atomic_testandclear_32 atomic_testandclear_int
|
||||
|
||||
/* Operations on pointers. */
|
||||
#define atomic_set_ptr(p, v) \
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user