Author: Armin Rigo <[email protected]>
Branch: c8-new-page-handling
Changeset: r1414:d6152847d126
Date: 2014-09-23 20:37 +0200
http://bitbucket.org/pypy/stmgc/changeset/d6152847d126/
Log: Progress one or two more tests.
diff --git a/c8/stm/core.c b/c8/stm/core.c
--- a/c8/stm/core.c
+++ b/c8/stm/core.c
@@ -5,17 +5,9 @@
/* ############# signal handler ############# */
-static void copy_bk_objs_in_page_from(int from_segnum, uintptr_t pagenum)
+static void _copy_from_undo_log(uintptr_t pagenum, struct stm_undo_s *undo,
+ struct stm_undo_s *end)
{
- /* looks at all bk copies of objects overlapping page 'pagenum' and
- copies the part in 'pagenum' back to the current segment */
- dprintf(("copy_bk_objs_in_page_from(%d, %lu)\n", from_segnum, pagenum));
-
- acquire_modified_objs_lock(from_segnum);
- struct list_s *list = get_priv_segment(from_segnum)->modified_old_objects;
- struct stm_undo_s *undo = (struct stm_undo_s *)list->items;
- struct stm_undo_s *end = (struct stm_undo_s *)(list->items + list->count);
-
for (; undo < end; undo++) {
object_t *obj = undo->object;
stm_char *oslice = ((stm_char *)obj) + SLICE_OFFSET(undo->slice);
@@ -26,40 +18,57 @@
memcpy(dst, undo->backup, SLICE_SIZE(undo->slice));
}
}
- release_modified_objs_lock(from_segnum);
}
-static void update_page_revision_from_to(uintptr_t pagenum,
- struct stm_commit_log_entry_s *from,
- struct stm_commit_log_entry_s *to)
+static void copy_bk_objs_in_page_from(int from_segnum, uintptr_t pagenum)
{
- /* walk the commit log and update the page 'pagenum' until we reach
- the same revision as our segment, or we reach the HEAD. */
+ /* looks at all bk copies of objects overlapping page 'pagenum' and
+ copies the part in 'pagenum' back to the current segment */
+ dprintf(("copy_bk_objs_in_page_from(%d, %lu)\n", from_segnum, pagenum));
+
+ struct list_s *list = get_priv_segment(from_segnum)->modified_old_objects;
+ struct stm_undo_s *undo = (struct stm_undo_s *)list->items;
+ struct stm_undo_s *end = (struct stm_undo_s *)(list->items + list->count);
+
+ _copy_from_undo_log(pagenum, undo, end);
+}
+
+static void go_to_the_future(uintptr_t pagenum,
+ struct stm_commit_log_entry_s *from,
+ struct stm_commit_log_entry_s *to)
+{
+ /* walk FORWARDS the commit log and update the page 'pagenum',
+ initially at revision 'from', until we reach the revision 'to'. */
assert(all_privatization_locks_acquired());
- volatile struct stm_commit_log_entry_s *cl;
- cl = (volatile struct stm_commit_log_entry_s *)from;
+ while (from != to) {
+ from = from->next;
- if (from == to)
- return;
+ struct stm_undo_s *undo = from->written;
+ struct stm_undo_s *end = from->written + from->written_count;
- while ((cl = cl->next)) {
- if (cl == (void *)-1)
- return;
+ _copy_from_undo_log(pagenum, undo, end);
+ }
+}
- OPT_ASSERT(cl->segment_num >= 0 && cl->segment_num < NB_SEGMENTS);
+static void go_to_the_past(uintptr_t pagenum,
+ struct stm_commit_log_entry_s *from,
+ struct stm_commit_log_entry_s *to)
+{
+ /* walk BACKWARDS the commit log and update the page 'pagenum',
+ initially at revision 'from', until we reach the revision 'to'. */
+ assert(all_privatization_locks_acquired());
- object_t *obj;
- size_t i = 0;
- while ((obj = cl->written[i].object)) {
- abort(); //_update_obj_from(cl->segment_num, obj, pagenum);
+ /* XXXXXXX Recursive algo for now, fix this! */
- i++;
- };
+ if (from != to) {
+ struct stm_commit_log_entry_s *cl = from->next;
+ go_to_the_past(pagenum, cl, to);
- /* last fully validated entry */
- if (cl == to)
- return;
+ struct stm_undo_s *undo = cl->written;
+ struct stm_undo_s *end = cl->written + cl->written_count;
+
+ _copy_from_undo_log(pagenum, undo, end);
}
}
@@ -96,23 +105,48 @@
/* this assert should be true for now... */
assert(shared_ref_count == 1);
+ /* acquire this lock, so that we know we should get a view
+ of the page we're about to copy that is consistent with the
+ backup copies in the other thread's 'modified_old_objects'. */
+ acquire_modified_objs_lock(shared_page_holder);
+
/* make our page private */
page_privatize_in(STM_SEGMENT->segment_num, pagenum);
assert(get_page_status_in(my_segnum, pagenum) == PAGE_PRIVATE);
- /* if there were modifications in the page, revert them: */
+ /* if there were modifications in the page, revert them. */
copy_bk_objs_in_page_from(shared_page_holder, pagenum);
- /* Note that we can't really read without careful locking
- 'get_priv_segment(shared_page_holder)->last_commit_log_entry'.
- Instead, we're just assuming that the current status of the
- page is xxxxxxxxxxxxxxx
- */
- abort();
+ /* we need to go from 'src_version' to 'target_version'. This
+ might need a walk into the past or the future. */
+ struct stm_commit_log_entry_s *src_version, *target_version, *c1, *c2;
+ src_version = get_priv_segment(shared_page_holder)->last_commit_log_entry;
+ target_version = STM_PSEGMENT->last_commit_log_entry;
- /* in case page is already newer, validate everything now to have a common
- revision for all pages */
- //_stm_validate(NULL, true);
+ c1 = src_version;
+ c2 = target_version;
+ while (1) {
+ if (c1 == target_version) {
+ go_to_the_future(pagenum, src_version, target_version);
+ break;
+ }
+ if (c2 == src_version) {
+ go_to_the_past(pagenum, src_version, target_version);
+ break;
+ }
+ c1 = c1->next;
+ if (c1 == (void *)-1 || c1 == NULL) {
+ go_to_the_past(pagenum, src_version, target_version);
+ break;
+ }
+ c2 = c2->next;
+ if (c2 == (void *)-1 || c2 == NULL) {
+ go_to_the_future(pagenum, src_version, target_version);
+ break;
+ }
+ }
+
+ release_modified_objs_lock(shared_page_holder);
}
static void _signal_handler(int sig, siginfo_t *siginfo, void *context)
@@ -210,6 +244,11 @@
struct stm_commit_log_entry_s *next_cl;
/* Don't check this 'cl'. This entry is already checked */
+ /* We need this lock to prevent a segfault handler in a different thread
+ from seeing inconsistent data. It could also be done by carefully
+ ordering things, but later. */
+ acquire_modified_objs_lock(STM_SEGMENT->segment_num);
+
bool needs_abort = false;
while ((next_cl = cl->next) != NULL) {
if (next_cl == (void *)-1) {
@@ -248,9 +287,12 @@
}
/* last fully validated entry */
+
STM_PSEGMENT->last_commit_log_entry = cl;
}
+ release_modified_objs_lock(STM_SEGMENT->segment_num);
+
if (needs_abort) {
if (free_if_abort != (void *)-1)
free(free_if_abort);
@@ -316,6 +358,7 @@
acquire_modified_objs_lock(STM_SEGMENT->segment_num);
list_clear(STM_PSEGMENT->modified_old_objects);
+ STM_PSEGMENT->last_commit_log_entry = new;
release_modified_objs_lock(STM_SEGMENT->segment_num);
}
_______________________________________________
pypy-commit mailing list
[email protected]
https://mail.python.org/mailman/listinfo/pypy-commit
