2021-01-04 10:26:59 +01:00
|
|
|
/* Copyright (C) 2012-2021 Free Software Foundation, Inc.
|
2012-05-01 17:48:28 +02:00
|
|
|
Contributed by Richard Henderson <rth@redhat.com>.
|
|
|
|
|
|
|
|
This file is part of the GNU Atomic Library (libatomic).
|
|
|
|
|
|
|
|
Libatomic is free software; you can redistribute it and/or modify it
|
|
|
|
under the terms of the GNU General Public License as published by
|
|
|
|
the Free Software Foundation; either version 3 of the License, or
|
|
|
|
(at your option) any later version.
|
|
|
|
|
|
|
|
Libatomic is distributed in the hope that it will be useful, but WITHOUT ANY
|
|
|
|
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
|
|
FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
|
|
|
more details.
|
|
|
|
|
|
|
|
Under Section 7 of GPL version 3, you are granted additional
|
|
|
|
permissions described in the GCC Runtime Library Exception, version
|
|
|
|
3.1, as published by the Free Software Foundation.
|
|
|
|
|
|
|
|
You should have received a copy of the GNU General Public License and
|
|
|
|
a copy of the GCC Runtime Library Exception along with this program;
|
|
|
|
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
|
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
|
|
|
|
#include "libatomic_i.h"
|
|
|
|
|
|
|
|
|
|
|
|
/* If we natively support the exchange, and if we're unconcerned with extra
|
|
|
|
barriers (e.g. fully in-order cpu for which barriers are a nop), then
|
|
|
|
go ahead and expand the operation inline. */
|
|
|
|
#if !defined(WANT_SPECIALCASE_RELAXED) && !defined(__OPTIMIZE_SIZE__)
|
|
|
|
# define EXACT_INLINE(N) \
|
|
|
|
if (C2(HAVE_ATOMIC_EXCHANGE_,N)) \
|
|
|
|
{ \
|
|
|
|
*PTR(N,rptr) = __atomic_exchange_n \
|
Avoid non constant memory model uses in libatomic
x86 ends up using non constant memory models for some of the libatomic
functions. These all end up as __ATOMIC_SEQ_CST. Just use this
directly. This avoids a new warning for non constant memory
models, which broke the bootstrap with -Werror
Passed bootstrap and test on x86_64-linux.
libatomic/:
2013-03-23 Andi Kleen <ak@linux.intel.com>
* gcas.c: (EXACT_INLINE): Use __ATOMIC_SEQ_CST.
* gexch.c: (EXACT_INLINE): Use __ATOMIC_SEQ_CST.
* gload.c: (EXACT_INLINE): Use __ATOMIC_SEQ_CST.
* gstore.c: (EXACT_INLINE): Use __ATOMIC_SEQ_CST.
diff --git a/libatomic/gcas.c b/libatomic/gcas.c
index edbf611..e3d77f3 100644
--- a/libatomic/gcas.c
+++ b/libatomic/gcas.c
@@ -32,7 +32,7 @@
# define EXACT_INLINE(N) \
if (C2(HAVE_ATOMIC_CAS_,N)) \
return __atomic_compare_exchange_n \
- (PTR(N,mptr), PTR(N,eptr), *PTR(N,dptr), false, smodel, fmodel)
+ (PTR(N,mptr), PTR(N,eptr), *PTR(N,dptr), false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)
#else
# define EXACT_INLINE(N)
#endif
diff --git a/libatomic/gexch.c b/libatomic/gexch.c
index 1999067..c8c8658 100644
--- a/libatomic/gexch.c
+++ b/libatomic/gexch.c
@@ -33,7 +33,7 @@
if (C2(HAVE_ATOMIC_EXCHANGE_,N)) \
{ \
*PTR(N,rptr) = __atomic_exchange_n \
- (PTR(N,mptr), *PTR(N,vptr), smodel); \
+ (PTR(N,mptr), *PTR(N,vptr), __ATOMIC_SEQ_CST); \
return; \
}
#else
diff --git a/libatomic/gload.c b/libatomic/gload.c
index df318d5..85865bd 100644
--- a/libatomic/gload.c
+++ b/libatomic/gload.c
@@ -32,7 +32,7 @@
# define EXACT_INLINE(N, DEST, SRC, DONE) \
if (C2(HAVE_ATOMIC_LDST_,N)) \
{ \
- DEST = __atomic_load_n (SRC, smodel); \
+ DEST = __atomic_load_n (SRC, __ATOMIC_SEQ_CST); \
DONE; \
}
#else
diff --git a/libatomic/gstore.c b/libatomic/gstore.c
index d571e58..84f9a8d 100644
--- a/libatomic/gstore.c
+++ b/libatomic/gstore.c
@@ -32,7 +32,7 @@
# define EXACT_INLINE(N) \
if (C2(HAVE_ATOMIC_LDST_,N)) \
{ \
- __atomic_store_n (PTR(N,mptr), *PTR(N,vptr), smodel); \
+ __atomic_store_n (PTR(N,mptr), *PTR(N,vptr), __ATOMIC_SEQ_CST); \
return; \
}
#else
From-SVN: r197017
2013-03-24 01:23:10 +01:00
|
|
|
(PTR(N,mptr), *PTR(N,vptr), __ATOMIC_SEQ_CST); \
|
2012-05-01 17:48:28 +02:00
|
|
|
return; \
|
|
|
|
}
|
|
|
|
#else
|
|
|
|
# define EXACT_INLINE(N)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
|
|
#define EXACT(N) \
|
|
|
|
do { \
|
|
|
|
if (!C2(HAVE_INT,N)) break; \
|
|
|
|
if ((uintptr_t)mptr & (N - 1)) break; \
|
|
|
|
EXACT_INLINE (N); \
|
|
|
|
*PTR(N,rptr) = C3(local_,exchange_,N) \
|
|
|
|
(PTR(N,mptr), *PTR(N,vptr), smodel); \
|
|
|
|
return; \
|
|
|
|
} while (0)
|
|
|
|
|
|
|
|
|
|
|
|
#define LARGER(N) \
|
|
|
|
do { \
|
|
|
|
if (!C2(HAVE_INT,N)) break; \
|
|
|
|
if (!C2(MAYBE_HAVE_ATOMIC_CAS_,N)) break; \
|
|
|
|
r = (uintptr_t)mptr & (N - 1); \
|
|
|
|
a = (uintptr_t)mptr & -N; \
|
|
|
|
if (r + n <= N) \
|
|
|
|
{ \
|
|
|
|
pre_barrier (smodel); \
|
|
|
|
u.C2(i,N) = *PTR(N,a); \
|
|
|
|
do { \
|
|
|
|
v = u; \
|
|
|
|
memcpy (v.b + r, vptr, n); \
|
|
|
|
} while (!(C2(HAVE_ATOMIC_CAS_,N) \
|
|
|
|
? __atomic_compare_exchange_n (PTR(N,a), \
|
|
|
|
&u.C2(i,N), v.C2(i,N), true, \
|
|
|
|
__ATOMIC_RELAXED, __ATOMIC_RELAXED) \
|
|
|
|
: C3(local_,compare_exchange_,N) (PTR(N,a), \
|
|
|
|
&u.C2(i,N), v.C2(i,N), \
|
|
|
|
__ATOMIC_RELAXED, __ATOMIC_RELAXED))); \
|
|
|
|
goto Lfinish; \
|
|
|
|
} \
|
|
|
|
} while (0)
|
|
|
|
|
|
|
|
|
|
|
|
static void __attribute__((noinline))
|
|
|
|
libat_exchange_large_inplace (size_t n, void *mptr, void *vptr)
|
|
|
|
{
|
|
|
|
#define BUF 1024
|
|
|
|
|
|
|
|
char temp[BUF];
|
|
|
|
size_t i = 0;
|
|
|
|
|
|
|
|
for (i = 0; n >= BUF; i += BUF, n -= BUF)
|
|
|
|
{
|
|
|
|
memcpy (temp, mptr + i, BUF);
|
|
|
|
memcpy (mptr + i, vptr + i, BUF);
|
|
|
|
memcpy (vptr + i, temp, BUF);
|
|
|
|
}
|
|
|
|
if (n > 0)
|
|
|
|
{
|
|
|
|
memcpy (temp, mptr + i, n);
|
|
|
|
memcpy (mptr + i, vptr + i, n);
|
|
|
|
memcpy (vptr + i, temp, n);
|
|
|
|
}
|
|
|
|
|
|
|
|
#undef BUF
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
libat_exchange (size_t n, void *mptr, void *vptr, void *rptr, int smodel)
|
|
|
|
{
|
|
|
|
union max_size_u u, v;
|
|
|
|
uintptr_t r, a;
|
|
|
|
|
|
|
|
switch (n)
|
|
|
|
{
|
|
|
|
case 0: return;
|
|
|
|
case 1: EXACT(1); goto L4;
|
|
|
|
case 2: EXACT(2); goto L4;
|
|
|
|
case 4: EXACT(4); goto L8;
|
|
|
|
case 8: EXACT(8); goto L16;
|
|
|
|
case 16: EXACT(16); break;
|
|
|
|
|
|
|
|
case 3: L4: LARGER(4); /* FALLTHRU */
|
|
|
|
case 5 ... 7: L8: LARGER(8); /* FALLTHRU */
|
|
|
|
case 9 ... 15: L16: LARGER(16); break;
|
|
|
|
|
|
|
|
Lfinish:
|
|
|
|
post_barrier (smodel);
|
|
|
|
memcpy (rptr, u.b + r, n);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
pre_seq_barrier (smodel);
|
|
|
|
libat_lock_n (mptr, n);
|
|
|
|
|
|
|
|
if (vptr != rptr)
|
|
|
|
{
|
|
|
|
memcpy (rptr, mptr, n);
|
|
|
|
memcpy (mptr, vptr, n);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
libat_exchange_large_inplace (n, mptr, vptr);
|
|
|
|
|
|
|
|
libat_unlock_n (mptr, n);
|
|
|
|
post_seq_barrier (smodel);
|
|
|
|
}
|
|
|
|
|
|
|
|
EXPORT_ALIAS (exchange);
|