padata, pcrypt: take CPU hotplug lock internally in padata_alloc_possible

With pcrypt's cpumask no longer used, take the CPU hotplug lock inside
padata_alloc_possible.

Useful later in the series for avoiding nested acquisition of the CPU
hotplug lock in padata when padata_alloc_possible is allocating an
unbound workqueue.

Without this patch, this nested acquisition would happen later in the
series:

      pcrypt_init_padata
        get_online_cpus
        alloc_padata_possible
          alloc_padata
            alloc_workqueue(WQ_UNBOUND)   // later in the series
              alloc_and_link_pwqs
                apply_wqattrs_lock
                  get_online_cpus         // recursive rwsem acquisition

Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Daniel Jordan 2019-09-05 21:40:26 -04:00 committed by Herbert Xu
parent 63d3578892
commit cc491d8e64
2 changed files with 9 additions and 12 deletions

View file

@ -308,8 +308,6 @@ static int pcrypt_init_padata(struct padata_instance **pinst, const char *name)
{
int ret = -ENOMEM;
get_online_cpus();
*pinst = padata_alloc_possible(name);
if (!*pinst)
return ret;
@ -318,8 +316,6 @@ static int pcrypt_init_padata(struct padata_instance **pinst, const char *name)
if (ret)
padata_free(*pinst);
put_online_cpus();
return ret;
}