mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-24 11:29:10 +00:00
db7f0b974f
and ifnet functions - add memory barriers to <machine/atomic.h> - update drivers to only conditionally define their own - add lockless producer / consumer ring buffer - remove ring buffer implementation from cxgb and update its callers - add if_transmit(struct ifnet *ifp, struct mbuf *m) to ifnet to allow drivers to efficiently manage multiple hardware queues (i.e. not serialize all packets through one ifq) - expose if_qflush to allow drivers to flush any driver managed queues This work was supported by Bitgravity Inc. and Chelsio Inc.
300 lines
8.7 KiB
C
300 lines
8.7 KiB
C
/*-
|
|
* Copyright (c) 1998 Doug Rabson.
|
|
* Copyright (c) 2001 Jake Burkholder.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* from: FreeBSD: src/sys/i386/include/atomic.h,v 1.20 2001/02/11
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#ifndef _MACHINE_ATOMIC_H_
|
|
#define _MACHINE_ATOMIC_H_
|
|
|
|
#include <machine/cpufunc.h>
|
|
|
|
/* Userland needs different ASI's. */
|
|
#ifdef _KERNEL
|
|
#define __ASI_ATOMIC ASI_N
|
|
#else
|
|
#define __ASI_ATOMIC ASI_P
|
|
#endif
|
|
|
|
#define mb() __asm__ __volatile__ ("membar #MemIssue": : :"memory")
|
|
#define wmb() mb()
|
|
#define rmb() mb()
|
|
|
|
/*
|
|
* Various simple arithmetic on memory which is atomic in the presence
|
|
* of interrupts and multiple processors. See atomic(9) for details.
|
|
* Note that efficient hardware support exists only for the 32 and 64
|
|
* bit variants; the 8 and 16 bit versions are not provided and should
|
|
* not be used in MI code.
|
|
*
|
|
* This implementation takes advantage of the fact that the sparc64
|
|
* cas instruction is both a load and a store. The loop is often coded
|
|
* as follows:
|
|
*
|
|
* do {
|
|
* expect = *p;
|
|
* new = expect + 1;
|
|
* } while (cas(p, expect, new) != expect);
|
|
*
|
|
* which performs an unnnecessary load on each iteration that the cas
|
|
* operation fails. Modified as follows:
|
|
*
|
|
* expect = *p;
|
|
* for (;;) {
|
|
* new = expect + 1;
|
|
* result = cas(p, expect, new);
|
|
* if (result == expect)
|
|
* break;
|
|
* expect = result;
|
|
* }
|
|
*
|
|
* the return value of cas is used to avoid the extra reload.
|
|
*
|
|
* The memory barriers provided by the acq and rel variants are intended
|
|
* to be sufficient for use of relaxed memory ordering. Due to the
|
|
* suggested assembly syntax of the membar operands containing a #
|
|
* character, they cannot be used in macros. The cmask and mmask bits
|
|
* are hard coded in machine/cpufunc.h and used here through macros.
|
|
* Hopefully sun will choose not to change the bit numbers.
|
|
*/
|
|
|
|
#define itype(sz) uint ## sz ## _t
|
|
|
|
#define atomic_cas_32(p, e, s) casa(p, e, s, __ASI_ATOMIC)
|
|
#define atomic_cas_64(p, e, s) casxa(p, e, s, __ASI_ATOMIC)
|
|
|
|
#define atomic_cas(p, e, s, sz) \
|
|
atomic_cas_ ## sz(p, e, s)
|
|
|
|
#define atomic_cas_acq(p, e, s, sz) ({ \
|
|
itype(sz) v; \
|
|
v = atomic_cas(p, e, s, sz); \
|
|
membar(LoadLoad | LoadStore); \
|
|
v; \
|
|
})
|
|
|
|
#define atomic_cas_rel(p, e, s, sz) ({ \
|
|
itype(sz) v; \
|
|
membar(LoadStore | StoreStore); \
|
|
v = atomic_cas(p, e, s, sz); \
|
|
v; \
|
|
})
|
|
|
|
#define atomic_op(p, op, v, sz) ({ \
|
|
itype(sz) e, r, s; \
|
|
for (e = *(volatile itype(sz) *)p;; e = r) { \
|
|
s = e op v; \
|
|
r = atomic_cas_ ## sz(p, e, s); \
|
|
if (r == e) \
|
|
break; \
|
|
} \
|
|
e; \
|
|
})
|
|
|
|
#define atomic_op_acq(p, op, v, sz) ({ \
|
|
itype(sz) t; \
|
|
t = atomic_op(p, op, v, sz); \
|
|
membar(LoadLoad | LoadStore); \
|
|
t; \
|
|
})
|
|
|
|
#define atomic_op_rel(p, op, v, sz) ({ \
|
|
itype(sz) t; \
|
|
membar(LoadStore | StoreStore); \
|
|
t = atomic_op(p, op, v, sz); \
|
|
t; \
|
|
})
|
|
|
|
#define atomic_load(p, sz) \
|
|
atomic_cas(p, 0, 0, sz)
|
|
|
|
#define atomic_load_acq(p, sz) ({ \
|
|
itype(sz) v; \
|
|
v = atomic_load(p, sz); \
|
|
membar(LoadLoad | LoadStore); \
|
|
v; \
|
|
})
|
|
|
|
#define atomic_load_clear(p, sz) ({ \
|
|
itype(sz) e, r; \
|
|
for (e = *(volatile itype(sz) *)p;; e = r) { \
|
|
r = atomic_cas(p, e, 0, sz); \
|
|
if (r == e) \
|
|
break; \
|
|
} \
|
|
e; \
|
|
})
|
|
|
|
#define atomic_store(p, v, sz) do { \
|
|
itype(sz) e, r; \
|
|
for (e = *(volatile itype(sz) *)p;; e = r) { \
|
|
r = atomic_cas(p, e, v, sz); \
|
|
if (r == e) \
|
|
break; \
|
|
} \
|
|
} while (0)
|
|
|
|
#define atomic_store_rel(p, v, sz) do { \
|
|
membar(LoadStore | StoreStore); \
|
|
atomic_store(p, v, sz); \
|
|
} while (0)
|
|
|
|
#define ATOMIC_GEN(name, ptype, vtype, atype, sz) \
|
|
\
|
|
static __inline vtype \
|
|
atomic_add_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op(p, +, v, sz)); \
|
|
} \
|
|
static __inline vtype \
|
|
atomic_add_acq_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op_acq(p, +, v, sz)); \
|
|
} \
|
|
static __inline vtype \
|
|
atomic_add_rel_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op_rel(p, +, v, sz)); \
|
|
} \
|
|
\
|
|
static __inline vtype \
|
|
atomic_clear_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op(p, &, ~v, sz)); \
|
|
} \
|
|
static __inline vtype \
|
|
atomic_clear_acq_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op_acq(p, &, ~v, sz)); \
|
|
} \
|
|
static __inline vtype \
|
|
atomic_clear_rel_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op_rel(p, &, ~v, sz)); \
|
|
} \
|
|
\
|
|
static __inline int \
|
|
atomic_cmpset_ ## name(volatile ptype p, vtype e, vtype s) \
|
|
{ \
|
|
return (((vtype)atomic_cas(p, e, s, sz)) == e); \
|
|
} \
|
|
static __inline int \
|
|
atomic_cmpset_acq_ ## name(volatile ptype p, vtype e, vtype s) \
|
|
{ \
|
|
return (((vtype)atomic_cas_acq(p, e, s, sz)) == e); \
|
|
} \
|
|
static __inline int \
|
|
atomic_cmpset_rel_ ## name(volatile ptype p, vtype e, vtype s) \
|
|
{ \
|
|
return (((vtype)atomic_cas_rel(p, e, s, sz)) == e); \
|
|
} \
|
|
\
|
|
static __inline vtype \
|
|
atomic_load_ ## name(volatile ptype p) \
|
|
{ \
|
|
return ((vtype)atomic_cas(p, 0, 0, sz)); \
|
|
} \
|
|
static __inline vtype \
|
|
atomic_load_acq_ ## name(volatile ptype p) \
|
|
{ \
|
|
return ((vtype)atomic_cas_acq(p, 0, 0, sz)); \
|
|
} \
|
|
\
|
|
static __inline vtype \
|
|
atomic_readandclear_ ## name(volatile ptype p) \
|
|
{ \
|
|
return ((vtype)atomic_load_clear(p, sz)); \
|
|
} \
|
|
\
|
|
static __inline vtype \
|
|
atomic_set_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op(p, |, v, sz)); \
|
|
} \
|
|
static __inline vtype \
|
|
atomic_set_acq_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op_acq(p, |, v, sz)); \
|
|
} \
|
|
static __inline vtype \
|
|
atomic_set_rel_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op_rel(p, |, v, sz)); \
|
|
} \
|
|
\
|
|
static __inline vtype \
|
|
atomic_subtract_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op(p, -, v, sz)); \
|
|
} \
|
|
static __inline vtype \
|
|
atomic_subtract_acq_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op_acq(p, -, v, sz)); \
|
|
} \
|
|
static __inline vtype \
|
|
atomic_subtract_rel_ ## name(volatile ptype p, atype v) \
|
|
{ \
|
|
return ((vtype)atomic_op_rel(p, -, v, sz)); \
|
|
} \
|
|
\
|
|
static __inline void \
|
|
atomic_store_ ## name(volatile ptype p, vtype v) \
|
|
{ \
|
|
atomic_store(p, v, sz); \
|
|
} \
|
|
static __inline void \
|
|
atomic_store_rel_ ## name(volatile ptype p, vtype v) \
|
|
{ \
|
|
atomic_store_rel(p, v, sz); \
|
|
}
|
|
|
|
ATOMIC_GEN(int, u_int *, u_int, u_int, 32);
|
|
ATOMIC_GEN(32, uint32_t *, uint32_t, uint32_t, 32);
|
|
|
|
ATOMIC_GEN(long, u_long *, u_long, u_long, 64);
|
|
ATOMIC_GEN(64, uint64_t *, uint64_t, uint64_t, 64);
|
|
|
|
ATOMIC_GEN(ptr, uintptr_t *, uintptr_t, uintptr_t, 64);
|
|
|
|
#define atomic_fetchadd_int atomic_add_int
|
|
#define atomic_fetchadd_32 atomic_add_32
|
|
#define atomic_fetchadd_long atomic_add_long
|
|
|
|
#undef ATOMIC_GEN
|
|
#undef atomic_cas
|
|
#undef atomic_cas_acq
|
|
#undef atomic_cas_rel
|
|
#undef atomic_op
|
|
#undef atomic_op_acq
|
|
#undef atomic_op_rel
|
|
#undef atomic_load_acq
|
|
#undef atomic_store_rel
|
|
#undef atomic_load_clear
|
|
|
|
#endif /* !_MACHINE_ATOMIC_H_ */
|