cpumask: convert rest of files in kernel/

Impact: Reduce stack usage, use new cpumask API.

Mainly changing cpumask_t to 'struct cpumask' and similar simple API
conversion.  Two conversions worth mentioning:

1) we use cpumask_any_but to avoid a temporary in kernel/softlockup.c,
2) Use cpumask_var_t in taskstats_user_cmd().

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>

5 files changed, 34 insertions, 27 deletions

diff --git a/include/linux/stop_machine.h b/include/linux/stop_machine.h
index faf1519b5adc..74d59a641362 100644
--- a/include/linux/stop_machine.h
+++ b/include/linux/stop_machine.h
@@ -23,7 +23,7 @@
  *
  * This can be thought of as a very heavy write lock, equivalent to
  * grabbing every spinlock in the kernel. */
-int stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus);
+int stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus);
 
 /**
  * __stop_machine: freeze the machine on all CPUs and run this function
@@ -34,11 +34,11 @@ int stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus);
  * Description: This is a special version of the above, which assumes cpus
  * won't come or go while it's being called.  Used by hotplug cpu.
  */
-int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus);
+int __stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus);
 #else
 
 static inline int stop_machine(int (*fn)(void *), void *data,
-                               const cpumask_t *cpus)
+                               const struct cpumask *cpus)
 {
         int ret;
         local_irq_disable();
diff --git a/kernel/power/poweroff.c b/kernel/power/poweroff.c
index 72016f051477..97890831e1b5 100644
--- a/kernel/power/poweroff.c
+++ b/kernel/power/poweroff.c
@@ -27,7 +27,7 @@ static DECLARE_WORK(poweroff_work, do_poweroff);
 static void handle_poweroff(int key, struct tty_struct *tty)
 {
         /* run sysrq poweroff on boot cpu */
-        schedule_work_on(first_cpu(cpu_online_map), &poweroff_work);
+        schedule_work_on(cpumask_first(cpu_online_mask), &poweroff_work);
 }
 
 static struct sysrq_key_op      sysrq_poweroff_op = {
diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index 492f0c72fec5..d9188c66278a 100644
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -310,10 +310,8 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
         case CPU_DOWN_PREPARE:
         case CPU_DOWN_PREPARE_FROZEN:
                 if (hotcpu == check_cpu) {
-                        cpumask_t temp_cpu_online_map = cpu_online_map;
-
-                        cpu_clear(hotcpu, temp_cpu_online_map);
-                        check_cpu = cpumask_any(&temp_cpu_online_map);
+                        /* Pick any other online cpu. */
+                        check_cpu = cpumask_any_but(cpu_online_mask, hotcpu);
                 }
                 break;
 
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 24e8ceacc388..286c41722e8c 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -69,10 +69,10 @@ static void stop_cpu(struct work_struct *unused)
         int err;
 
         if (!active_cpus) {
-                if (cpu == first_cpu(cpu_online_map))
+                if (cpu == cpumask_first(cpu_online_mask))
                         smdata = &active;
         } else {
-                if (cpu_isset(cpu, *active_cpus))
+                if (cpumask_test_cpu(cpu, active_cpus))
                         smdata = &active;
         }
         /* Simple state machine */
@@ -109,7 +109,7 @@ static int chill(void *unused)
         return 0;
 }
 
-int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
+int __stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus)
 {
         struct work_struct *sm_work;
         int i, ret;
@@ -142,7 +142,7 @@ int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
         return ret;
 }
 
-int stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
+int stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus)
 {
         int ret;
 
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index 6d7dc4ec4aa5..888adbcca30c 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -290,18 +290,17 @@ ret:
         return;
 }
 
-static int add_del_listener(pid_t pid, cpumask_t *maskp, int isadd)
+static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd)
 {
         struct listener_list *listeners;
         struct listener *s, *tmp;
         unsigned int cpu;
-        cpumask_t mask = *maskp;
 
-        if (!cpus_subset(mask, cpu_possible_map))
+        if (!cpumask_subset(mask, cpu_possible_mask))
                 return -EINVAL;
 
         if (isadd == REGISTER) {
-                for_each_cpu_mask_nr(cpu, mask) {
+                for_each_cpu(cpu, mask) {
                         s = kmalloc_node(sizeof(struct listener), GFP_KERNEL,
                                          cpu_to_node(cpu));
                         if (!s)
@@ -320,7 +319,7 @@ static int add_del_listener(pid_t pid, cpumask_t *maskp, int isadd)
 
         /* Deregister or cleanup */
 cleanup:
-        for_each_cpu_mask_nr(cpu, mask) {
+        for_each_cpu(cpu, mask) {
                 listeners = &per_cpu(listener_array, cpu);
                 down_write(&listeners->sem);
                 list_for_each_entry_safe(s, tmp, &listeners->list, list) {
@@ -335,7 +334,7 @@ cleanup:
         return 0;
 }
 
-static int parse(struct nlattr *na, cpumask_t *mask)
+static int parse(struct nlattr *na, struct cpumask *mask)
 {
         char *data;
         int len;
@@ -428,23 +427,33 @@ err:
 
 static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
 {
-        int rc = 0;
+        int rc;
         struct sk_buff *rep_skb;
         struct taskstats *stats;
         size_t size;
-        cpumask_t mask;
+        cpumask_var_t mask;
+
+        if (!alloc_cpumask_var(&mask, GFP_KERNEL))
+                return -ENOMEM;
 
-        rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], &mask);
+        rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask);
         if (rc < 0)
-                return rc;
-        if (rc == 0)
-                return add_del_listener(info->snd_pid, &mask, REGISTER);
+                goto free_return_rc;
+        if (rc == 0) {
+                rc = add_del_listener(info->snd_pid, mask, REGISTER);
+                goto free_return_rc;
+        }
 
-        rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], &mask);
+        rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask);
         if (rc < 0)
+                goto free_return_rc;
+        if (rc == 0) {
+                rc = add_del_listener(info->snd_pid, mask, DEREGISTER);
+free_return_rc:
+                free_cpumask_var(mask);
                 return rc;
-        if (rc == 0)
-                return add_del_listener(info->snd_pid, &mask, DEREGISTER);
+        }
+        free_cpumask_var(mask);
 
         /*
          * Size includes space for nested attributes