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authorRickard Green <[email protected]>2010-06-17 10:23:50 +0200
committerRickard Green <[email protected]>2010-08-10 11:41:14 +0200
commit300b419486c1ca88e33938f182d5d5a8b90fb73f (patch)
tree55c37d5fb042bf6b3b5f56d89c9238a7e22f8b29 /erts/include/internal/tile/atomic.h
parentc1e94fa9a6fe4ae717d35dfbd1b628dc2e06d26a (diff)
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Rewrite ethread library
Large parts of the ethread library have been rewritten. The ethread library is an Erlang runtime system internal, portable thread library used by the runtime system itself. Most notable improvement is a reader optimized rwlock implementation which dramatically improve the performance of read-lock/read-unlock operations on multi processor systems by avoiding ping-ponging of the rwlock cache lines. The reader optimized rwlock implementation is used by miscellaneous rwlocks in the runtime system that are known to be read-locked frequently, and can be enabled on ETS tables by passing the `{read_concurrency, true}' option upon table creation. See the documentation of `ets:new/2' for more information. The ethread library can now also use the libatomic_ops library for atomic memory accesses. This makes it possible for the Erlang runtime system to utilize optimized atomic operations on more platforms than before. Use the `--with-libatomic_ops=PATH' configure command line argument when specifying where the libatomic_ops installation is located. The libatomic_ops library can be downloaded from: http://www.hpl.hp.com/research/linux/atomic_ops/ The changed API of the ethread library has also caused modifications in the Erlang runtime system. Preparations for the to come "delayed deallocation" feature has also been done since it depends on the ethread library. Note: When building for x86, the ethread library will now use instructions that first appeared on the pentium 4 processor. If you want the runtime system to be compatible with older processors (back to 486) you need to pass the `--enable-ethread-pre-pentium4-compatibility' configure command line argument when configuring the system.
Diffstat (limited to 'erts/include/internal/tile/atomic.h')
-rw-r--r--erts/include/internal/tile/atomic.h67
1 files changed, 55 insertions, 12 deletions
diff --git a/erts/include/internal/tile/atomic.h b/erts/include/internal/tile/atomic.h
index 5e4c7ac9fe..69569d82d1 100644
--- a/erts/include/internal/tile/atomic.h
+++ b/erts/include/internal/tile/atomic.h
@@ -34,7 +34,7 @@ typedef struct {
#define ETHR_MEMORY_BARRIER __insn_mf()
-#ifdef ETHR_TRY_INLINE_FUNCS
+#if defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_AUX_IMPL__)
static ETHR_INLINE void
ethr_native_atomic_init(ethr_native_atomic_t *var, long i)
@@ -45,7 +45,6 @@ ethr_native_atomic_init(ethr_native_atomic_t *var, long i)
static ETHR_INLINE void
ethr_native_atomic_set(ethr_native_atomic_t *var, long i)
{
- __insn_mf();
atomic_exchange_acq(&var->counter, i);
}
@@ -58,28 +57,24 @@ ethr_native_atomic_read(ethr_native_atomic_t *var)
static ETHR_INLINE void
ethr_native_atomic_add(ethr_native_atomic_t *var, long incr)
{
- __insn_mf();
atomic_add(&var->counter, incr);
}
static ETHR_INLINE void
ethr_native_atomic_inc(ethr_native_atomic_t *var)
{
- __insn_mf();
atomic_increment(&var->counter);
}
static ETHR_INLINE void
ethr_native_atomic_dec(ethr_native_atomic_t *var)
{
- __insn_mf();
atomic_decrement(&var->counter);
}
static ETHR_INLINE long
ethr_native_atomic_add_return(ethr_native_atomic_t *var, long incr)
{
- __insn_mf();
return atomic_exchange_and_add(&var->counter, incr) + incr;
}
@@ -98,33 +93,81 @@ ethr_native_atomic_dec_return(ethr_native_atomic_t *var)
static ETHR_INLINE long
ethr_native_atomic_and_retold(ethr_native_atomic_t *var, long mask)
{
- /* Implement a barrier suitable for a mutex unlock. */
- __insn_mf();
return atomic_and_val(&var->counter, mask);
}
static ETHR_INLINE long
ethr_native_atomic_or_retold(ethr_native_atomic_t *var, long mask)
{
- __insn_mf();
return atomic_or_val(&var->counter, mask);
}
static ETHR_INLINE long
ethr_native_atomic_xchg(ethr_native_atomic_t *var, long val)
{
- __insn_mf();
return atomic_exchange_acq(&var->counter, val);
}
static ETHR_INLINE long
ethr_native_atomic_cmpxchg(ethr_native_atomic_t *var, long new, long expected)
{
- /* Implement a barrier suitable for a mutex unlock. */
- __insn_mf();
return atomic_compare_and_exchange_val_acq(&var->counter, new, expected);
}
+/*
+ * Atomic ops with at least specified barriers.
+ */
+
+static ETHR_INLINE long
+ethr_native_atomic_read_acqb(ethr_native_atomic_t *var)
+{
+ long res = ethr_native_atomic_read(var);
+ ETHR_MEMORY_BARRIER;
+ return res;
+}
+
+static ETHR_INLINE long
+ethr_native_atomic_inc_return_acqb(ethr_native_atomic_t *var)
+{
+ long res = ethr_native_atomic_inc_return(var);
+ ETHR_MEMORY_BARRIER;
+ return res;
+}
+
+static ETHR_INLINE void
+ethr_native_atomic_set_relb(ethr_native_atomic_t *var, long val)
+{
+ ETHR_MEMORY_BARRIER;
+ ethr_native_atomic_set(var, val);
+}
+
+static ETHR_INLINE void
+ethr_native_atomic_dec_relb(ethr_native_atomic_t *var)
+{
+ ETHR_MEMORY_BARRIER;
+ ethr_native_atomic_dec(var);
+}
+
+static ETHR_INLINE long
+ethr_native_atomic_dec_return_relb(ethr_native_atomic_t *var)
+{
+ ETHR_MEMORY_BARRIER;
+ return ethr_native_atomic_dec_return(var);
+}
+
+static ETHR_INLINE long
+ethr_native_atomic_cmpxchg_acqb(ethr_native_atomic_t *var, long new, long exp)
+{
+ return ethr_native_atomic_cmpxchg(var, new, exp);
+}
+
+static ETHR_INLINE long
+ethr_native_atomic_cmpxchg_relb(ethr_native_atomic_t *var, long new, long exp)
+{
+ ETHR_MEMORY_BARRIER;
+ return ethr_native_atomic_cmpxchg(var, new, exp);
+}
+
#endif /* ETHR_TRY_INLINE_FUNCS */
#endif /* ETHREAD_TILE_ATOMIC_H */