Author: Armin Rigo <[email protected]>
Branch: c5
Changeset: r566:3c9724af3fb5
Date: 2013-12-19 14:58 +0100
http://bitbucket.org/pypy/stmgc/changeset/3c9724af3fb5/
Log: in-progress
diff --git a/c5/core.c b/c5/core.c
--- a/c5/core.c
+++ b/c5/core.c
@@ -87,15 +87,15 @@
char _pad0[CACHE_LINE_SIZE];
};
union {
- uint64_t index_page_never_used;
+ uint64_t volatile index_page_never_used;
char _pad1[CACHE_LINE_SIZE];
};
union {
- unsigned int next_transaction_version; /* always EVEN */
+ unsigned int volatile next_transaction_version; /* always EVEN */
char _pad2[CACHE_LINE_SIZE];
};
union {
- struct write_history_s *most_recent_committed_transaction;
+ struct write_history_s *volatile most_recent_committed_transaction;
char _pad3[CACHE_LINE_SIZE];
};
};
@@ -166,6 +166,13 @@
return result;
}
+static struct write_history_s *_reserve_page_write_history(void)
+{
+ struct page_header_s *newpage = _stm_reserve_page();
+ newpage->kind = PGKIND_WRITE_HISTORY;
+ return (struct write_history_s *)(newpage + 1);
+}
+
static uint32_t get_pgoff(struct page_header_s *page)
{
@@ -216,9 +223,17 @@
assert(page->pgoff == new_pgoff);
struct write_history_s *cur = stm_local.writes_by_this_transaction;
+ size_t history_size_max = 4096 - (((uintptr_t)cur) & 4095);
+ if (sizeof(*cur) + (cur->nb_updates + 1) * 8 > history_size_max) {
+ /* The buffer would overflow its page. Allocate a new one. */
+ cur = _reserve_page_write_history();
+ cur->previous_older_transaction =
+ stm_local.writes_by_this_transaction;
+ cur->transaction_version = stm_transaction_version;
+ cur->nb_updates = 0;
+ stm_local.writes_by_this_transaction = cur;
+ }
uint64_t i = cur->nb_updates++;
- size_t history_size_max = 4096 - (((uintptr_t)cur) & 4095);
- assert(sizeof(*cur) + cur->nb_updates * 8 <= history_size_max);//XXX
cur->updates[i * 2 + 0] = get_local_index(page);
cur->updates[i * 2 + 1] = new_pgoff;
}
@@ -487,15 +502,11 @@
char *next, *page_limit = (char *)cur;
page_limit += 4096 - (((uintptr_t)page_limit) & 4095);
next = (char *)(cur + 1) + 8 * cur->nb_updates;
- if (page_limit - next < sizeof(struct write_history_s) + 8)
- cur = NULL;
- else
+ if (page_limit - next >= sizeof(struct write_history_s) + 8)
cur = (struct write_history_s *)next;
}
if (cur == NULL) {
- struct page_header_s *newpage = _stm_reserve_page();
- newpage->kind = PGKIND_WRITE_HISTORY;
- cur = (struct write_history_s *)(newpage + 1);
+ cur = _reserve_page_write_history();
}
cur->previous_older_transaction = NULL;
cur->transaction_version = stm_transaction_version;
@@ -527,6 +538,12 @@
int conflict = 0;
//fprintf(stderr, "stm_stop_transaction\n");
+ struct write_history_s *cur_head = stm_local.writes_by_this_transaction;
+ struct write_history_s *cur_tail = cur_head;
+ while (cur_tail->previous_older_transaction != NULL) {
+ cur_tail = cur_tail->previous_older_transaction;
+ }
+
while (1) {
struct write_history_s *hist = d->most_recent_committed_transaction;
if (hist != stm_local.base_page_mapping) {
@@ -536,10 +553,9 @@
else
continue; /* retry from the start of the loop */
}
- struct write_history_s *cur = stm_local.writes_by_this_transaction;
- cur->previous_older_transaction = hist;
+ cur_tail->previous_older_transaction = hist;
if (__sync_bool_compare_and_swap(&d->most_recent_committed_transaction,
- hist, cur))
+ hist, cur_head))
break;
}
_______________________________________________
pypy-commit mailing list
[email protected]
https://mail.python.org/mailman/listinfo/pypy-commit
