[PATCH] sched: export sched_set/getaffinity (was Re: [PATCH 3/3] vhost: apply cpumask and cgroup to vhost pollers)
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: 2010-06-25 10:15:54
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On Thu, Jun 24, 2010 at 03:45:51PM -0700, Sridhar Samudrala wrote:
On Thu, 2010-06-24 at 11:11 +0300, Michael S. Tsirkin wrote:quoted
On Sun, May 30, 2010 at 10:25:01PM +0200, Tejun Heo wrote:quoted
Apply the cpumask and cgroup of the initializing task to the created vhost poller. Based on Sridhar Samudrala's patch. Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Sridhar Samudrala <redacted>I wanted to apply this, but modpost fails: ERROR: "sched_setaffinity" [drivers/vhost/vhost_net.ko] undefined! ERROR: "sched_getaffinity" [drivers/vhost/vhost_net.ko] undefined! Did you try building as a module?In my original implementation, i had these calls in workqueue.c. Now that these are moved to vhost.c which can be built as a module, these symbols need to be exported. The following patch fixes the build issue with vhost as a module. Signed-off-by: Sridhar Samudrala <redacted>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Works for me. To simplify dependencies, I'd like to queue this together with the chost patches through net-next. Ack to this?
quoted hunk ↗ jump to hunk
diff --git a/kernel/sched.c b/kernel/sched.c index 3c2a54f..15a0c6f 100644 --- a/kernel/sched.c +++ b/kernel/sched.c@@ -4837,6 +4837,7 @@ out_put_task: put_online_cpus(); return retval; } +EXPORT_SYMBOL_GPL(sched_setaffinity); static int get_user_cpu_mask(unsigned long __user *user_mask_ptr,unsigned len, struct cpumask *new_mask)@@ -4900,6 +4901,7 @@ out_unlock: return retval; } +EXPORT_SYMBOL_GPL(sched_getaffinity); /** * sys_sched_getaffinity - get the cpu affinity of a processquoted
quoted
--- drivers/vhost/vhost.c | 36 +++++++++++++++++++++++++++++++----- 1 file changed, 31 insertions(+), 5 deletions(-) Index: work/drivers/vhost/vhost.c ===================================================================--- work.orig/drivers/vhost/vhost.c +++ work/drivers/vhost/vhost.c@@ -23,6 +23,7 @@ #include <linux/highmem.h> #include <linux/slab.h> #include <linux/kthread.h> +#include <linux/cgroup.h> #include <linux/net.h> #include <linux/if_packet.h>@@ -176,12 +177,30 @@ repeat: long vhost_dev_init(struct vhost_dev *dev, struct vhost_virtqueue *vqs, int nvqs) { - struct task_struct *poller; - int i; + struct task_struct *poller = NULL; + cpumask_var_t mask; + int i, ret = -ENOMEM; + + if (!alloc_cpumask_var(&mask, GFP_KERNEL)) + goto out; poller = kthread_create(vhost_poller, dev, "vhost-%d", current->pid); - if (IS_ERR(poller)) - return PTR_ERR(poller); + if (IS_ERR(poller)) { + ret = PTR_ERR(poller); + goto out; + } + + ret = sched_getaffinity(current->pid, mask); + if (ret) + goto out; + + ret = sched_setaffinity(poller->pid, mask); + if (ret) + goto out; + + ret = cgroup_attach_task_current_cg(poller); + if (ret) + goto out; dev->vqs = vqs; dev->nvqs = nvqs;@@ -202,7 +221,14 @@ long vhost_dev_init(struct vhost_dev *de vhost_poll_init(&dev->vqs[i].poll, dev->vqs[i].handle_kick, POLLIN, dev); } - return 0; + + wake_up_process(poller); /* avoid contributing to loadavg */ + ret = 0; +out: + if (ret) + kthread_stop(poller); + free_cpumask_var(mask); + return ret; } /* Caller should have device mutex */-- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html