diff options
author | Eric Dumazet <eric.dumazet@gmail.com> | 2011-03-23 02:30:44 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-23 03:44:01 +0300 |
commit | 207205a2ba2655652fe46a60b49838af6c16a919 (patch) | |
tree | 4309aa7cd5cf39c805219001e0ed8ec5b71e4d5e /kernel/kthread.c | |
parent | b6a84016bd2598e35ead635147fa53619982648d (diff) |
kthread: NUMA aware kthread_create_on_node()
All kthreads being created from a single helper task, they all use memory
from a single node for their kernel stack and task struct.
This patch suite creates kthread_create_on_node(), adding a 'cpu' parameter
to parameters already used by kthread_create().
This parameter serves in allocating memory for the new kthread on its
memory node if possible.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/kthread.c')
-rw-r--r-- | kernel/kthread.c | 31 |
1 files changed, 25 insertions, 6 deletions
diff --git a/kernel/kthread.c b/kernel/kthread.c index c55afba990a3..684ab3f7dd72 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -27,6 +27,7 @@ struct kthread_create_info /* Information passed to kthread() from kthreadd. */ int (*threadfn)(void *data); void *data; + int node; /* Result passed back to kthread_create() from kthreadd. */ struct task_struct *result; @@ -98,10 +99,23 @@ static int kthread(void *_create) do_exit(ret); } +/* called from do_fork() to get node information for about to be created task */ +int tsk_fork_get_node(struct task_struct *tsk) +{ +#ifdef CONFIG_NUMA + if (tsk == kthreadd_task) + return tsk->pref_node_fork; +#endif + return numa_node_id(); +} + static void create_kthread(struct kthread_create_info *create) { int pid; +#ifdef CONFIG_NUMA + current->pref_node_fork = create->node; +#endif /* We want our own signal handler (we take no signals by default). */ pid = kernel_thread(kthread, create, CLONE_FS | CLONE_FILES | SIGCHLD); if (pid < 0) { @@ -111,15 +125,18 @@ static void create_kthread(struct kthread_create_info *create) } /** - * kthread_create - create a kthread. + * kthread_create_on_node - create a kthread. * @threadfn: the function to run until signal_pending(current). * @data: data ptr for @threadfn. + * @node: memory node number. * @namefmt: printf-style name for the thread. * * Description: This helper function creates and names a kernel * thread. The thread will be stopped: use wake_up_process() to start * it. See also kthread_run(). * + * If thread is going to be bound on a particular cpu, give its node + * in @node, to get NUMA affinity for kthread stack, or else give -1. * When woken, the thread will run @threadfn() with @data as its * argument. @threadfn() can either call do_exit() directly if it is a * standalone thread for which noone will call kthread_stop(), or @@ -129,15 +146,17 @@ static void create_kthread(struct kthread_create_info *create) * * Returns a task_struct or ERR_PTR(-ENOMEM). */ -struct task_struct *kthread_create(int (*threadfn)(void *data), - void *data, - const char namefmt[], - ...) +struct task_struct *kthread_create_on_node(int (*threadfn)(void *data), + void *data, + int node, + const char namefmt[], + ...) { struct kthread_create_info create; create.threadfn = threadfn; create.data = data; + create.node = node; init_completion(&create.done); spin_lock(&kthread_create_lock); @@ -164,7 +183,7 @@ struct task_struct *kthread_create(int (*threadfn)(void *data), } return create.result; } -EXPORT_SYMBOL(kthread_create); +EXPORT_SYMBOL(kthread_create_on_node); /** * kthread_bind - bind a just-created kthread to a cpu. |