From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx153.postini.com [74.125.245.153]) by kanga.kvack.org (Postfix) with SMTP id 0BAFA6B0071 for ; Wed, 4 Jul 2012 19:17:23 -0400 (EDT) Date: Thu, 5 Jul 2012 01:14:25 +0200 From: Andrea Arcangeli Subject: Re: [PATCH 09/40] autonuma: introduce kthread_bind_node() Message-ID: <20120704231425.GP25743@redhat.com> References: <1340888180-15355-1-git-send-email-aarcange@redhat.com> <1340888180-15355-10-git-send-email-aarcange@redhat.com> <20120630045013.GB3975@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120630045013.GB3975@localhost.localdomain> Sender: owner-linux-mm@kvack.org List-ID: To: Konrad Rzeszutek Wilk Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Hillf Danton , Dan Smith , Peter Zijlstra , Linus Torvalds , Andrew Morton , Thomas Gleixner , Ingo Molnar , Paul Turner , Suresh Siddha , Mike Galbraith , "Paul E. McKenney" , Lai Jiangshan , Bharata B Rao , Lee Schermerhorn , Rik van Riel , Johannes Weiner , Srivatsa Vaddagiri , Christoph Lameter , Alex Shi , Mauricio Faria de Oliveira , Konrad Rzeszutek Wilk , Don Morris , Benjamin Herrenschmidt On Sat, Jun 30, 2012 at 12:50:14AM -0400, Konrad Rzeszutek Wilk wrote: > On Thu, Jun 28, 2012 at 02:55:49PM +0200, Andrea Arcangeli wrote: > > This function makes it easy to bind the per-node knuma_migrated > > threads to their respective NUMA nodes. Those threads take memory from > > the other nodes (in round robin with a incoming queue for each remote > > node) and they move that memory to their local node. > > > > Signed-off-by: Andrea Arcangeli > > --- > > include/linux/kthread.h | 1 + > > include/linux/sched.h | 2 +- > > kernel/kthread.c | 23 +++++++++++++++++++++++ > > 3 files changed, 25 insertions(+), 1 deletions(-) > > > > diff --git a/include/linux/kthread.h b/include/linux/kthread.h > > index 0714b24..e733f97 100644 > > --- a/include/linux/kthread.h > > +++ b/include/linux/kthread.h > > @@ -33,6 +33,7 @@ struct task_struct *kthread_create_on_node(int (*threadfn)(void *data), > > }) > > > > void kthread_bind(struct task_struct *k, unsigned int cpu); > > +void kthread_bind_node(struct task_struct *p, int nid); > > int kthread_stop(struct task_struct *k); > > int kthread_should_stop(void); > > bool kthread_freezable_should_stop(bool *was_frozen); > > diff --git a/include/linux/sched.h b/include/linux/sched.h > > index 4059c0f..699324c 100644 > > --- a/include/linux/sched.h > > +++ b/include/linux/sched.h > > @@ -1792,7 +1792,7 @@ extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t * > > #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ > > #define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */ > > #define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */ > > -#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */ > > +#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpus */ > > #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ > > #define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */ > > #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ > > diff --git a/kernel/kthread.c b/kernel/kthread.c > > index 3d3de63..48b36f9 100644 > > --- a/kernel/kthread.c > > +++ b/kernel/kthread.c > > @@ -234,6 +234,29 @@ void kthread_bind(struct task_struct *p, unsigned int cpu) > > EXPORT_SYMBOL(kthread_bind); > > > > /** > > + * kthread_bind_node - bind a just-created kthread to the CPUs of a node. > > + * @p: thread created by kthread_create(). > > + * @nid: node (might not be online, must be possible) for @k to run on. > > + * > > + * Description: This function is equivalent to set_cpus_allowed(), > > + * except that @nid doesn't need to be online, and the thread must be > > + * stopped (i.e., just returned from kthread_create()). > > + */ > > +void kthread_bind_node(struct task_struct *p, int nid) > > +{ > > + /* Must have done schedule() in kthread() before we set_task_cpu */ > > + if (!wait_task_inactive(p, TASK_UNINTERRUPTIBLE)) { > > + WARN_ON(1); > > + return; > > + } > > + > > + /* It's safe because the task is inactive. */ > > + do_set_cpus_allowed(p, cpumask_of_node(nid)); > > + p->flags |= PF_THREAD_BOUND; > > +} > > +EXPORT_SYMBOL(kthread_bind_node); > > _GPL ? /** * kthread_bind - bind a just-created kthread to a cpu. * @p: thread created by kthread_create(). * @cpu: cpu (might not be online, must be possible) for @k to run on. * * Description: This function is equivalent to set_cpus_allowed(), * except that @cpu doesn't need to be online, and the thread must be * stopped (i.e., just returned from kthread_create()). */ void kthread_bind(struct task_struct *p, unsigned int cpu) { /* Must have done schedule() in kthread() before we set_task_cpu */ if (!wait_task_inactive(p, TASK_UNINTERRUPTIBLE)) { WARN_ON(1); return; } /* It's safe because the task is inactive. */ do_set_cpus_allowed(p, cpumask_of(cpu)); p->flags |= PF_THREAD_BOUND; } EXPORT_SYMBOL(kthread_bind); /** * kthread_bind_node - bind a just-created kthread to the CPUs of a node. * @p: thread created by kthread_create(). * @nid: node (might not be online, must be possible) for @k to run on. * * Description: This function is equivalent to set_cpus_allowed(), * except that @nid doesn't need to be online, and the thread must be * stopped (i.e., just returned from kthread_create()). */ void kthread_bind_node(struct task_struct *p, int nid) { /* Must have done schedule() in kthread() before we set_task_cpu */ if (!wait_task_inactive(p, TASK_UNINTERRUPTIBLE)) { WARN_ON(1); return; } /* It's safe because the task is inactive. */ do_set_cpus_allowed(p, cpumask_of_node(nid)); p->flags |= PF_THREAD_BOUND; } EXPORT_SYMBOL(kthread_bind_node); The above should explain why it's not _GPL right now. As far as AutoNUMA is concerned I can drop the EXPORT_SYMBOL completely and not allow modules to call this. In fact I could have coded this inside autonuma too. I can change it to _GPL, drop the EXPORT_SYMBOL or move it inside the autonuma code, let me know what you prefer. If I hear nothing I won't make changes. Thanks, Andrea -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org