diff options
author | Daniel Jordan <daniel.m.jordan@oracle.com> | 2019-09-06 04:40:26 +0300 |
---|---|---|
committer | Herbert Xu <herbert@gondor.apana.org.au> | 2019-09-13 14:15:40 +0300 |
commit | cc491d8e6486c56e07e60d9992cd56f63dc9fd6c (patch) | |
tree | e8564355420beff9baaeeffe853585e9f90b7ddc /kernel/padata.c | |
parent | 63d3578892dc00d165623184b793045257e01083 (diff) |
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>
Diffstat (limited to 'kernel/padata.c')
-rw-r--r-- | kernel/padata.c | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/kernel/padata.c b/kernel/padata.c index 9a17922ec436..8a362923c488 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -955,8 +955,6 @@ static struct kobj_type padata_attr_type = { * @name: used to identify the instance * @pcpumask: cpumask that will be used for padata parallelization * @cbcpumask: cpumask that will be used for padata serialization - * - * Must be called from a cpus_read_lock() protected region */ static struct padata_instance *padata_alloc(const char *name, const struct cpumask *pcpumask, @@ -974,11 +972,13 @@ static struct padata_instance *padata_alloc(const char *name, if (!pinst->wq) goto err_free_inst; + get_online_cpus(); + if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL)) - goto err_free_wq; + goto err_put_cpus; if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) { free_cpumask_var(pinst->cpumask.pcpu); - goto err_free_wq; + goto err_put_cpus; } if (!padata_validate_cpumask(pinst, pcpumask) || !padata_validate_cpumask(pinst, cbcpumask)) @@ -1002,12 +1002,16 @@ static struct padata_instance *padata_alloc(const char *name, #ifdef CONFIG_HOTPLUG_CPU cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, &pinst->node); #endif + + put_online_cpus(); + return pinst; err_free_masks: free_cpumask_var(pinst->cpumask.pcpu); free_cpumask_var(pinst->cpumask.cbcpu); -err_free_wq: +err_put_cpus: + put_online_cpus(); destroy_workqueue(pinst->wq); err_free_inst: kfree(pinst); @@ -1021,12 +1025,9 @@ err: * parallel workers. * * @name: used to identify the instance - * - * Must be called from a cpus_read_lock() protected region */ struct padata_instance *padata_alloc_possible(const char *name) { - lockdep_assert_cpus_held(); return padata_alloc(name, cpu_possible_mask, cpu_possible_mask); } EXPORT_SYMBOL(padata_alloc_possible); |