Author: Armin Rigo <[email protected]>
Branch:
Changeset: r473:ef085b2228e4
Date: 2013-08-03 14:33 +0200
http://bitbucket.org/pypy/stmgc/changeset/ef085b2228e4/
Log: stm_repeat_write_barrier()
diff --git a/c4/et.c b/c4/et.c
--- a/c4/et.c
+++ b/c4/et.c
@@ -618,6 +618,16 @@
}
}
+gcptr stm_RepeatWriteBarrier(gcptr P)
+{
+ assert(!(P->h_tid & GCFLAG_IMMUTABLE));
+ assert(is_private(P));
+ assert(P->h_tid & GCFLAG_WRITE_BARRIER);
+ P->h_tid &= ~GCFLAG_WRITE_BARRIER;
+ gcptrlist_insert(&thread_descriptor->old_objects_to_trace, P);
+ return P;
+}
+
gcptr stm_WriteBarrier(gcptr P)
{
assert(!(P->h_tid & GCFLAG_IMMUTABLE));
diff --git a/c4/et.h b/c4/et.h
--- a/c4/et.h
+++ b/c4/et.h
@@ -198,6 +198,7 @@
gcptr stm_WriteBarrier(gcptr);
gcptr stm_RepeatReadBarrier(gcptr);
gcptr stm_ImmutReadBarrier(gcptr);
+gcptr stm_RepeatWriteBarrier(gcptr);
gcptr _stm_nonrecord_barrier(gcptr); /* debugging: read barrier, but
not recording anything */
int _stm_is_private(gcptr); /* debugging */
diff --git a/c4/stmgc.h b/c4/stmgc.h
--- a/c4/stmgc.h
+++ b/c4/stmgc.h
@@ -79,12 +79,17 @@
- a different optimization is to read immutable fields: in order
to do that, use stm_immut_read_barrier(), which only activates
on stubs.
+
+ - stm_repeat_write_barrier() can be used on an object on which
+ we already did stm_write_barrier(), but a potential collection
+ can have occurred.
*/
#if 0 // (optimized version below)
gcptr stm_read_barrier(gcptr);
gcptr stm_write_barrier(gcptr);
gcptr stm_repeat_read_barrier(gcptr);
gcptr stm_immut_read_barrier(gcptr);
+gcptr stm_repeat_write_barrier(gcptr); /* <= always returns its argument */
#endif
/* start a new transaction, calls callback(), and when it returns
@@ -204,5 +209,10 @@
stm_ImmutReadBarrier(obj) \
: (obj))
+#define stm_repeat_write_barrier(obj) \
+ (UNLIKELY((obj)->h_tid & GCFLAG_WRITE_BARRIER) ? \
+ stm_RepeatWriteBarrier(obj) \
+ : (obj))
+
#endif
diff --git a/c4/test/support.py b/c4/test/support.py
--- a/c4/test/support.py
+++ b/c4/test/support.py
@@ -59,6 +59,7 @@
gcptr stm_write_barrier(gcptr);
gcptr stm_repeat_read_barrier(gcptr);
gcptr stm_immut_read_barrier(gcptr);
+ gcptr stm_repeat_write_barrier(gcptr);
void stm_perform_transaction(gcptr arg, int (*callback)(gcptr, int));
void stm_commit_transaction(void);
void stm_begin_inevitable_transaction(void);
diff --git a/c4/test/test_et.py b/c4/test/test_et.py
--- a/c4/test/test_et.py
+++ b/c4/test/test_et.py
@@ -745,3 +745,20 @@
assert lib.stm_read_barrier(p2) == p2
assert lib.stm_read_barrier(pstub) == p2
assert lib.stm_read_barrier(p) == p2
+
+def test_repeat_write_barrier():
+ n = nalloc_refs(1)
+ lib.stm_push_root(n)
+ minor_collect()
+ n = lib.stm_pop_root()
+ q = nalloc(HDR + WORD)
+ lib.rawsetlong(q, 0, 1298719)
+ n1 = lib.stm_repeat_write_barrier(n)
+ assert n1 == n
+ lib.rawsetptr(n, 0, q)
+ lib.stm_push_root(n)
+ minor_collect()
+ n1 = lib.stm_pop_root()
+ assert n1 == n
+ q = lib.rawgetptr(n, 0)
+ assert lib.rawgetlong(q, 0) == 1298719
_______________________________________________
pypy-commit mailing list
[email protected]
http://mail.python.org/mailman/listinfo/pypy-commit
