knfsd: convert knfsd to kthread API
This patch is rather large, but I couldn't figure out a way to break it
up that would remain bisectable. It does several things:
- change svc_thread_fn typedef to better match what kthread_create expects
- change svc_pool_map_set_cpumask to be more kthread friendly. Make it
take a task arg and and get rid of the "oldmask"
- have svc_set_num_threads call kthread_create directly
- eliminate __svc_create_thread
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 7bffaff..03a9f1a 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -18,6 +18,7 @@
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/module.h>
+#include <linux/kthread.h>
#include <linux/sunrpc/types.h>
#include <linux/sunrpc/xdr.h>
@@ -291,15 +292,14 @@
/*
- * Set the current thread's cpus_allowed mask so that it
+ * Set the given thread's cpus_allowed mask so that it
* will only run on cpus in the given pool.
- *
- * Returns 1 and fills in oldmask iff a cpumask was applied.
*/
-static inline int
-svc_pool_map_set_cpumask(unsigned int pidx, cpumask_t *oldmask)
+static inline void
+svc_pool_map_set_cpumask(struct task_struct *task, unsigned int pidx)
{
struct svc_pool_map *m = &svc_pool_map;
+ unsigned int node = m->pool_to[pidx];
/*
* The caller checks for sv_nrpools > 1, which
@@ -307,26 +307,17 @@
*/
BUG_ON(m->count == 0);
- switch (m->mode)
- {
- default:
- return 0;
+ switch (m->mode) {
case SVC_POOL_PERCPU:
{
- unsigned int cpu = m->pool_to[pidx];
-
- *oldmask = current->cpus_allowed;
- set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
- return 1;
+ set_cpus_allowed_ptr(task, &cpumask_of_cpu(node));
+ break;
}
case SVC_POOL_PERNODE:
{
- unsigned int node = m->pool_to[pidx];
node_to_cpumask_ptr(nodecpumask, node);
-
- *oldmask = current->cpus_allowed;
- set_cpus_allowed_ptr(current, nodecpumask);
- return 1;
+ set_cpus_allowed_ptr(task, nodecpumask);
+ break;
}
}
}
@@ -579,47 +570,6 @@
EXPORT_SYMBOL(svc_prepare_thread);
/*
- * Create a thread in the given pool. Caller must hold BKL or another lock to
- * serialize access to the svc_serv struct. On a NUMA or SMP machine, with a
- * multi-pool serv, the thread will be restricted to run on the cpus belonging
- * to the pool.
- */
-static int
-__svc_create_thread(svc_thread_fn func, struct svc_serv *serv,
- struct svc_pool *pool)
-{
- struct svc_rqst *rqstp;
- int error = -ENOMEM;
- int have_oldmask = 0;
- cpumask_t uninitialized_var(oldmask);
-
- rqstp = svc_prepare_thread(serv, pool);
- if (IS_ERR(rqstp)) {
- error = PTR_ERR(rqstp);
- goto out;
- }
-
- if (serv->sv_nrpools > 1)
- have_oldmask = svc_pool_map_set_cpumask(pool->sp_id, &oldmask);
-
- error = kernel_thread((int (*)(void *)) func, rqstp, 0);
-
- if (have_oldmask)
- set_cpus_allowed(current, oldmask);
-
- if (error < 0)
- goto out_thread;
- svc_sock_update_bufs(serv);
- error = 0;
-out:
- return error;
-
-out_thread:
- svc_exit_thread(rqstp);
- goto out;
-}
-
-/*
* Choose a pool in which to create a new thread, for svc_set_num_threads
*/
static inline struct svc_pool *
@@ -688,7 +638,9 @@
int
svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
{
- struct task_struct *victim;
+ struct svc_rqst *rqstp;
+ struct task_struct *task;
+ struct svc_pool *chosen_pool;
int error = 0;
unsigned int state = serv->sv_nrthreads-1;
@@ -704,18 +656,34 @@
/* create new threads */
while (nrservs > 0) {
nrservs--;
- __module_get(serv->sv_module);
- error = __svc_create_thread(serv->sv_function, serv,
- choose_pool(serv, pool, &state));
- if (error < 0) {
- module_put(serv->sv_module);
+ chosen_pool = choose_pool(serv, pool, &state);
+
+ rqstp = svc_prepare_thread(serv, chosen_pool);
+ if (IS_ERR(rqstp)) {
+ error = PTR_ERR(rqstp);
break;
}
+
+ __module_get(serv->sv_module);
+ task = kthread_create(serv->sv_function, rqstp, serv->sv_name);
+ if (IS_ERR(task)) {
+ error = PTR_ERR(task);
+ module_put(serv->sv_module);
+ svc_exit_thread(rqstp);
+ break;
+ }
+
+ rqstp->rq_task = task;
+ if (serv->sv_nrpools > 1)
+ svc_pool_map_set_cpumask(task, chosen_pool->sp_id);
+
+ svc_sock_update_bufs(serv);
+ wake_up_process(task);
}
/* destroy old threads */
while (nrservs < 0 &&
- (victim = choose_victim(serv, pool, &state)) != NULL) {
- send_sig(serv->sv_kill_signal, victim, 1);
+ (task = choose_victim(serv, pool, &state)) != NULL) {
+ send_sig(serv->sv_kill_signal, task, 1);
nrservs++;
}