malloc: Initiate tcache shutdown even without allocations [BZ #28028]

Message ID 87czs3kbck.fsf@oldenburg.str.redhat.com
State Committed
Commit dfec225ee1972488bb48a8b67a2c4a13010c334a
Headers
Series malloc: Initiate tcache shutdown even without allocations [BZ #28028] |

Checks

Context Check Description
dj/TryBot-apply_patch success Patch applied to master at the time it was sent
dj/TryBot-32bit success Build for i686

Commit Message

Florian Weimer June 30, 2021, 8:25 a.m. UTC
  From: JeffyChen <jeffy.chen@rock-chips.com>

After commit 1e26d35193efbb29239c710a4c46a64708643320 ("malloc: Fix
tcache leak after thread destruction [BZ #22111]"),
tcache_shutting_down is still not early enough.  When we detach a
thread with no tcache allocated, tcache_shutting_down would still be
false.

---
 malloc/malloc.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
  

Comments

DJ Delorie July 2, 2021, 1:23 a.m. UTC | #1
Florian Weimer <fweimer@redhat.com> writes:
> From: JeffyChen <jeffy.chen@rock-chips.com>
>
> After commit 1e26d35193efbb29239c710a4c46a64708643320 ("malloc: Fix
> tcache leak after thread destruction [BZ #22111]"),
> tcache_shutting_down is still not early enough.  When we detach a
> thread with no tcache allocated, tcache_shutting_down would still be
> false.

LGTM
Reviewed-by: DJ Delorie <dj@redhat.com>

> ---
>  malloc/malloc.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/malloc/malloc.c b/malloc/malloc.c
> index 0e2e1747e0..bb9a1642aa 100644
> --- a/malloc/malloc.c
> +++ b/malloc/malloc.c
> @@ -3144,12 +3144,13 @@ tcache_thread_shutdown (void)
>    int i;
>    tcache_perthread_struct *tcache_tmp = tcache;
>  
> +  tcache_shutting_down = true;
> +
>    if (!tcache)
>      return;
>  
>    /* Disable the tcache and prevent it from being reinitialized.  */
>    tcache = NULL;
> -  tcache_shutting_down = true;
>  
>    /* Free all of the entries and the tcache itself back to the arena
>       heap for coalescing.  */
  

Patch

diff --git a/malloc/malloc.c b/malloc/malloc.c
index 0e2e1747e0..bb9a1642aa 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -3144,12 +3144,13 @@  tcache_thread_shutdown (void)
   int i;
   tcache_perthread_struct *tcache_tmp = tcache;
 
+  tcache_shutting_down = true;
+
   if (!tcache)
     return;
 
   /* Disable the tcache and prevent it from being reinitialized.  */
   tcache = NULL;
-  tcache_shutting_down = true;
 
   /* Free all of the entries and the tcache itself back to the arena
      heap for coalescing.  */