outline rare tcache_get codepaths

This commit is contained in:
Ben Maurer 2014-04-15 13:28:37 -07:00
parent 9b0cbf0850
commit a7619b7fa5
3 changed files with 43 additions and 33 deletions

View File

@ -384,6 +384,7 @@ tcache_event
tcache_event_hard tcache_event_hard
tcache_flush tcache_flush
tcache_get tcache_get
tcache_get_hard
tcache_initialized tcache_initialized
tcache_maxclass tcache_maxclass
tcache_salloc tcache_salloc

View File

@ -110,6 +110,7 @@ void tcache_bin_flush_large(tcache_bin_t *tbin, size_t binind, unsigned rem,
tcache_t *tcache); tcache_t *tcache);
void tcache_arena_associate(tcache_t *tcache, arena_t *arena); void tcache_arena_associate(tcache_t *tcache, arena_t *arena);
void tcache_arena_dissociate(tcache_t *tcache); void tcache_arena_dissociate(tcache_t *tcache);
tcache_t *tcache_get_hard(tcache_t *tcache, bool create);
tcache_t *tcache_create(arena_t *arena); tcache_t *tcache_create(arena_t *arena);
void tcache_destroy(tcache_t *tcache); void tcache_destroy(tcache_t *tcache);
void tcache_thread_cleanup(void *arg); void tcache_thread_cleanup(void *arg);
@ -220,39 +221,7 @@ tcache_get(bool create)
if ((uintptr_t)tcache <= (uintptr_t)TCACHE_STATE_MAX) { if ((uintptr_t)tcache <= (uintptr_t)TCACHE_STATE_MAX) {
if (tcache == TCACHE_STATE_DISABLED) if (tcache == TCACHE_STATE_DISABLED)
return (NULL); return (NULL);
if (tcache == NULL) { tcache = tcache_get_hard(tcache, create);
if (create == false) {
/*
* Creating a tcache here would cause
* allocation as a side effect of free().
* Ordinarily that would be okay since
* tcache_create() failure is a soft failure
* that doesn't propagate. However, if TLS
* data are freed via free() as in glibc,
* subtle corruption could result from setting
* a TLS variable after its backing memory is
* freed.
*/
return (NULL);
}
if (tcache_enabled_get() == false) {
tcache_enabled_set(false); /* Memoize. */
return (NULL);
}
return (tcache_create(choose_arena(NULL)));
}
if (tcache == TCACHE_STATE_PURGATORY) {
/*
* Make a note that an allocator function was called
* after tcache_thread_cleanup() was called.
*/
tcache = TCACHE_STATE_REINCARNATED;
tcache_tsd_set(&tcache);
return (NULL);
}
if (tcache == TCACHE_STATE_REINCARNATED)
return (NULL);
not_reached();
} }
return (tcache); return (tcache);

View File

@ -265,6 +265,46 @@ tcache_arena_dissociate(tcache_t *tcache)
} }
} }
tcache_t *
tcache_get_hard(tcache_t *tcache, bool create)
{
if (tcache == NULL) {
if (create == false) {
/*
* Creating a tcache here would cause
* allocation as a side effect of free().
* Ordinarily that would be okay since
* tcache_create() failure is a soft failure
* that doesn't propagate. However, if TLS
* data are freed via free() as in glibc,
* subtle corruption could result from setting
* a TLS variable after its backing memory is
* freed.
*/
return (NULL);
}
if (tcache_enabled_get() == false) {
tcache_enabled_set(false); /* Memoize. */
return (NULL);
}
return (tcache_create(choose_arena(NULL)));
}
if (tcache == TCACHE_STATE_PURGATORY) {
/*
* Make a note that an allocator function was called
* after tcache_thread_cleanup() was called.
*/
tcache = TCACHE_STATE_REINCARNATED;
tcache_tsd_set(&tcache);
return (NULL);
}
if (tcache == TCACHE_STATE_REINCARNATED)
return (NULL);
not_reached();
return (NULL);
}
tcache_t * tcache_t *
tcache_create(arena_t *arena) tcache_create(arena_t *arena)
{ {