diff options
Diffstat (limited to 'pkgs/development/libraries/db/register-race-fix.patch')
| -rw-r--r-- | pkgs/development/libraries/db/register-race-fix.patch | 47 |
1 files changed, 0 insertions, 47 deletions
diff --git a/pkgs/development/libraries/db/register-race-fix.patch b/pkgs/development/libraries/db/register-race-fix.patch deleted file mode 100644 index bb05c966e5bd..000000000000 --- a/pkgs/development/libraries/db/register-race-fix.patch +++ /dev/null @@ -1,47 +0,0 @@ -diff -rc db-4.5.20-orig/env/env_register.c db-4.5.20/env/env_register.c -*** db-4.5.20-orig/env/env_register.c 2006-09-09 16:29:04.000000000 +0200 ---- db-4.5.20/env/env_register.c 2007-05-16 21:13:27.000000000 +0200 -*************** -*** 255,260 **** ---- 255,262 ---- - buf[nr - 1] = '\0'; - } - -+ //sleep(3); -+ - pos = (off_t)lcnt * PID_LEN; - if (REGISTRY_LOCK(dbenv, pos, 1) == 0) { - if ((ret = REGISTRY_UNLOCK(dbenv, pos)) != 0) -*************** -*** 361,366 **** ---- 363,392 ---- - if (recovery_failed) - goto err; - -+ //sleep(5); -+ -+ /* -+ * Acquire an exclusive lock to prevent a race like this: -+ * -+ * 1) Process X is about to exit and process Y is just -+ * starting. -+ * 2) Process Y reads X's slot. -+ * 3) Process X clears its slot. -+ * 4) Process Y sees that X's slot isn't cleared yet (since it -+ * just read the old value). -+ * 5) Process X closes the registry, releases the lock on its -+ * slot. -+ * 6) Process Y tries to acquire X's slot and succeeds, so it -+ * concludes that X died and recovery is needed. -+ * -+ * A more efficient solution to this problem would be to let -+ * __envreg_add acquire the lock on a slot first, and *then* -+ * read the slot (instead of the other way around). Then we -+ * wouldn't need the exclusive lock here. -+ */ -+ if ((ret = REGISTRY_EXCL_LOCK(dbenv, 0)) != 0) -+ goto err; -+ - /* - * Why isn't an exclusive lock necessary to discard a DB_ENV handle? - * |