Found this while trying to use pool debugging to track down an issue
in Serf. Apparently testing pool debugging hasn't been much of a
priority, heh.
Related to this, with lifetime and owner checking enabled, some of our
tests break; I haven't tracked these down yet, but the symptoms are
that the test program aborts when it tries to destroy a pool, due to
ownership checks; apparently the pool is destroyed by a different
thread than the one that created it. This happens in testlockperf,
testmutexscope and testall.
Given that this is a likely scenario when multiple threads create
pools, and then the main thread calls apr_terminate(), I wonder if
these ownership checks are necessary. Or, conversely, if they should
be disabled during [global] pool destruction. They're actually
triggered by apr_pool_clear(), which /should/ pass a strict ownership
check under normal circumstances.
-- Brane
--
On 2025/08/07 06:19:52 something wrote:
> Author: brane
> Date: Thu Aug 7 06:19:52 2025
> New Revision: 1927658
>
> Log:
> Fix pool debugging. With lifetime or owner checks enabled, pools couldn't
> even be created, except for the global pool which is a special case.
>
> * memory/unix/apr_pools.c
> (struct apr_pool_t): Add an 'unmanaged' member for pool-debug mode.
> The lifetime checks must be skipped for unmanaged pools, since they
> inevitably fail: apr_pool_is_child_of() expects all pools to have a
> parent, which obviously is not the case for unmanaged pools.
>
> (apr_pool_create_ex_debug): Create the pool's mutex after the parent
> has been assigned, because that involves an allocation which triggers
> a lifetime check which ... well, see above.
>
> (apr_pool_create_unmanaged): Set the pool->unmanaged flag and create the
> pool's mutex after the owner and allocator have been assigned. A pool
> without the owner set fails the ownershhip check, and without an
> allocator it's sort of hard to allocate space for the mutex.
>
> Modified:
> apr/apr/trunk/memory/unix/apr_pools.c
>
> Modified: apr/apr/trunk/memory/unix/apr_pools.c
> ==============================================================================
> --- apr/apr/trunk/memory/unix/apr_pools.c Thu Aug 7 05:08:51 2025
(r1927657)
> +++ apr/apr/trunk/memory/unix/apr_pools.c Thu Aug 7 06:19:52 2025
(r1927658)
> @@ -600,6 +600,7 @@ struct apr_pool_t {
> apr_os_thread_t owner;
> apr_thread_mutex_t *mutex;
> #endif /* APR_HAS_THREADS */
> + int unmanaged;
> #endif /* APR_POOL_DEBUG */
> #ifdef NETWARE
> apr_os_proc_t owner_proc;
> @@ -1619,7 +1620,8 @@ static void apr_pool_check_lifetime(apr_
> * people have searched for the top level parent and
> * started to use that...
> */
> - if (pool == global_pool || global_pool == NULL)
> + if (pool == global_pool || global_pool == NULL
> + || (pool->parent == NULL && pool->unmanaged))
> return;
>
> /* Lifetime
> @@ -2063,6 +2065,22 @@ APR_DECLARE(apr_status_t) apr_pool_creat
> pool->owner_proc = (apr_os_proc_t)getnlmhandle();
> #endif /* defined(NETWARE) */
>
> + if ((pool->parent = parent) != NULL) {
> + pool_lock(parent)
> +
> + if ((pool->sibling = parent->child) != NULL)
> + pool->sibling->ref = &pool->sibling;
> +
> + parent->child = pool;
> + pool->ref = &parent->child;
> +
> + pool_unlock(parent);
> + }
> + else {
> + pool->sibling = NULL;
> + pool->ref = NULL;
> + }
> +
> #if APR_HAS_THREADS
> if (parent == NULL || parent->allocator != allocator) {
> apr_status_t rv;
> @@ -2086,22 +2104,6 @@ APR_DECLARE(apr_status_t) apr_pool_creat
> }
> #endif /* APR_HAS_THREADS */
>
> - if ((pool->parent = parent) != NULL) {
> - pool_lock(parent);
> -
> - if ((pool->sibling = parent->child) != NULL)
> - pool->sibling->ref = &pool->sibling;
> -
> - parent->child = pool;
> - pool->ref = &parent->child;
> -
> - pool_unlock(parent);
> - }
> - else {
> - pool->sibling = NULL;
> - pool->ref = NULL;
> - }
> -
> #if (APR_POOL_DEBUG & APR_POOL_DEBUG_VERBOSE)
> apr_pool_log_event(pool, "CREATE", file_line, 1);
> #endif /* (APR_POOL_DEBUG & APR_POOL_DEBUG_VERBOSE) */
> @@ -2130,11 +2132,30 @@ APR_DECLARE(apr_status_t) apr_pool_creat
>
> memset(pool, 0, SIZEOF_POOL_T);
>
> + pool->unmanaged = 1;
> pool->abort_fn = abort_fn;
> pool->tag = file_line;
> pool->file_line = file_line;
>
> #if APR_HAS_THREADS
> + pool->owner = apr_os_thread_current();
> +#endif /* APR_HAS_THREADS */
> +#ifdef NETWARE
> + pool->owner_proc = (apr_os_proc_t)getnlmhandle();
> +#endif /* defined(NETWARE) */
> +
> + if ((pool_allocator = allocator) == NULL) {
> + apr_status_t rv;
> + if ((rv = apr_allocator_create(&pool_allocator)) != APR_SUCCESS) {
> + if (abort_fn)
> + abort_fn(rv);
> + return rv;
> + }
> + pool_allocator->owner = pool;
> + }
> + pool->allocator = pool_allocator;
> +
> +#if APR_HAS_THREADS
> {
> apr_status_t rv;
>
> @@ -2154,24 +2175,6 @@ APR_DECLARE(apr_status_t) apr_pool_creat
> }
> #endif /* APR_HAS_THREADS */
>
> -#if APR_HAS_THREADS
> - pool->owner = apr_os_thread_current();
> -#endif /* APR_HAS_THREADS */
> -#ifdef NETWARE
> - pool->owner_proc = (apr_os_proc_t)getnlmhandle();
> -#endif /* defined(NETWARE) */
> -
> - if ((pool_allocator = allocator) == NULL) {
> - apr_status_t rv;
> - if ((rv = apr_allocator_create(&pool_allocator)) != APR_SUCCESS) {
> - if (abort_fn)
> - abort_fn(rv);
> - return rv;
> - }
> - pool_allocator->owner = pool;
> - }
> - pool->allocator = pool_allocator;
> -
> #if (APR_POOL_DEBUG & APR_POOL_DEBUG_VERBOSE)
> apr_pool_log_event(pool, "CREATEU", file_line, 1);
> #endif /* (APR_POOL_DEBUG & APR_POOL_DEBUG_VERBOSE) */
>
>
