[PATCH] fill_tgid: cleanup delays accounting

[powerpc.git] / kernel / taskstats.c

diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index 2ed4040..8adfb80 100644 (file)
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -18,7 +18,9 @@
 
 #include <linux/kernel.h>
 #include <linux/taskstats_kern.h>
+#include <linux/tsacct_kern.h>
 #include <linux/delayacct.h>
+#include <linux/tsacct_kern.h>
 #include <linux/cpumask.h>
 #include <linux/percpu.h>
 #include <net/genetlink.h>
@@ -75,7 +77,7 @@ static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp,
        /*
         * If new attributes are added, please revisit this allocation
         */
-       skb = nlmsg_new(size, GFP_KERNEL);
+       skb = nlmsg_new(genlmsg_total_size(size), GFP_KERNEL);
        if (!skb)
                return -ENOMEM;
 
@@ -172,21 +174,19 @@ static void send_cpu_listeners(struct sk_buff *skb, unsigned int cpu)
        up_write(&listeners->sem);
 }
 
-static int fill_pid(pid_t pid, struct task_struct *pidtsk,
+static int fill_pid(pid_t pid, struct task_struct *tsk,
                struct taskstats *stats)
 {
        int rc = 0;
-       struct task_struct *tsk = pidtsk;
 
-       if (!pidtsk) {
-               read_lock(&tasklist_lock);
+       if (!tsk) {
+               rcu_read_lock();
                tsk = find_task_by_pid(pid);
-               if (!tsk) {
-                       read_unlock(&tasklist_lock);
+               if (tsk)
+                       get_task_struct(tsk);
+               rcu_read_unlock();
+               if (!tsk)
                        return -ESRCH;
-               }
-               get_task_struct(tsk);
-               read_unlock(&tasklist_lock);
        } else
                get_task_struct(tsk);
 
@@ -198,7 +198,13 @@ static int fill_pid(pid_t pid, struct task_struct *pidtsk,
         */
 
        delayacct_add_tsk(stats, tsk);
+
+       /* fill in basic acct fields */
        stats->version = TASKSTATS_VERSION;
+       bacct_add_tsk(stats, tsk);
+
+       /* fill in extended acct fields */
+       xacct_add_tsk(stats, tsk);
 
        /* Define err: label here if needed */
        put_task_struct(tsk);
@@ -206,39 +212,30 @@ static int fill_pid(pid_t pid, struct task_struct *pidtsk,
 
 }
 
-static int fill_tgid(pid_t tgid, struct task_struct *tgidtsk,
+static int fill_tgid(pid_t tgid, struct task_struct *first,
                struct taskstats *stats)
 {
-       struct task_struct *tsk, *first;
+       struct task_struct *tsk;
        unsigned long flags;
+       int rc = -ESRCH;
 
        /*
         * Add additional stats from live tasks except zombie thread group
         * leaders who are already counted with the dead tasks
         */
-       first = tgidtsk;
-       if (!first) {
-               read_lock(&tasklist_lock);
+       rcu_read_lock();
+       if (!first)
                first = find_task_by_pid(tgid);
-               if (!first) {
-                       read_unlock(&tasklist_lock);
-                       return -ESRCH;
-               }
-               get_task_struct(first);
-               read_unlock(&tasklist_lock);
-       } else
-               get_task_struct(first);
 
-       /* Start with stats from dead tasks */
-       spin_lock_irqsave(&first->signal->stats_lock, flags);
+       if (!first || !lock_task_sighand(first, &flags))
+               goto out;
+
        if (first->signal->stats)
                memcpy(stats, first->signal->stats, sizeof(*stats));
-       spin_unlock_irqrestore(&first->signal->stats_lock, flags);
 
        tsk = first;
-       read_lock(&tasklist_lock);
        do {
-               if (tsk->exit_state == EXIT_ZOMBIE && thread_group_leader(tsk))
+               if (tsk->exit_state)
                        continue;
                /*
                 * Accounting subsystem can call its functions here to
@@ -249,15 +246,18 @@ static int fill_tgid(pid_t tgid, struct task_struct *tgidtsk,
                delayacct_add_tsk(stats, tsk);
 
        } while_each_thread(first, tsk);
-       read_unlock(&tasklist_lock);
-       stats->version = TASKSTATS_VERSION;
 
+       unlock_task_sighand(first, &flags);
+       rc = 0;
+out:
+       rcu_read_unlock();
+
+       stats->version = TASKSTATS_VERSION;
        /*
         * Accounting subsytems can also add calls here to modify
         * fields of taskstats.
         */
-
-       return 0;
+       return rc;
 }
 
 
@@ -265,7 +265,7 @@ static void fill_tgid_exit(struct task_struct *tsk)
 {
        unsigned long flags;
 
-       spin_lock_irqsave(&tsk->signal->stats_lock, flags);
+       spin_lock_irqsave(&tsk->sighand->siglock, flags);
        if (!tsk->signal->stats)
                goto ret;
 
@@ -277,7 +277,7 @@ static void fill_tgid_exit(struct task_struct *tsk)
         */
        delayacct_add_tsk(tsk->signal->stats, tsk);
 ret:
-       spin_unlock_irqrestore(&tsk->signal->stats_lock, flags);
+       spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
        return;
 }
 
@@ -453,15 +453,10 @@ void taskstats_exit_send(struct task_struct *tsk, struct taskstats *tidstats,
        size_t size;
        int is_thread_group;
        struct nlattr *na;
-       unsigned long flags;
 
        if (!family_registered || !tidstats)
                return;
 
-       spin_lock_irqsave(&tsk->signal->stats_lock, flags);
-       is_thread_group = tsk->signal->stats ? 1 : 0;
-       spin_unlock_irqrestore(&tsk->signal->stats_lock, flags);
-
        rc = 0;
        /*
         * Size includes space for nested attributes
@@ -469,6 +464,7 @@ void taskstats_exit_send(struct task_struct *tsk, struct taskstats *tidstats,
        size = nla_total_size(sizeof(u32)) +
                nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
 
+       is_thread_group = (tsk->signal->stats != NULL);
        if (is_thread_group)
                size = 2 * size;        /* PID + STATS + TGID + STATS */