On 04/12/2017 10:10 AM, Hillf Danton wrote: > On April 11, 2017 10:06 PM Vlastimil Babka wrote: >> >> static void cpuset_change_task_nodemask(struct task_struct *tsk, >> nodemask_t *newmems) >> { >> - bool need_loop; >> - >> task_lock(tsk); >> - /* >> - * Determine if a loop is necessary if another thread is doing >> - * read_mems_allowed_begin(). If at least one node remains unchanged and >> - * tsk does not have a mempolicy, then an empty nodemask will not be >> - * possible when mems_allowed is larger than a word. >> - */ >> - need_loop = task_has_mempolicy(tsk) || >> - !nodes_intersects(*newmems, tsk->mems_allowed); >> >> - if (need_loop) { >> - local_irq_disable(); >> - write_seqcount_begin(&tsk->mems_allowed_seq); >> - } >> + local_irq_disable(); >> + write_seqcount_begin(&tsk->mems_allowed_seq); >> >> - nodes_or(tsk->mems_allowed, tsk->mems_allowed, *newmems); >> mpol_rebind_task(tsk, newmems); >> tsk->mems_allowed = *newmems; >> >> - if (need_loop) { >> - write_seqcount_end(&tsk->mems_allowed_seq); >> - local_irq_enable(); >> - } >> + write_seqcount_end(&tsk->mems_allowed_seq); >> > Doubt if we'd listen irq again. Ugh, thanks for catching this. Looks like my testing config didn't have lockup detectors enabled. >> task_unlock(tsk); >> } >> -- >> 2.12.2 > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>