taskstats: split fill_pid function

Separate the finding of a task_struct by pid or tgid from filling the
taskstats data. This makes the code more readable.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michael Holzheu 2010-10-27 15:34:44 -07:00 committed by Linus Torvalds
parent 9323312592
commit 3d9e0cf1fe

View File

@ -175,22 +175,8 @@ static void send_cpu_listeners(struct sk_buff *skb,
up_write(&listeners->sem);
}
static int fill_pid(pid_t pid, struct task_struct *tsk,
struct taskstats *stats)
static void fill_stats(struct task_struct *tsk, struct taskstats *stats)
{
int rc = 0;
if (!tsk) {
rcu_read_lock();
tsk = find_task_by_vpid(pid);
if (tsk)
get_task_struct(tsk);
rcu_read_unlock();
if (!tsk)
return -ESRCH;
} else
get_task_struct(tsk);
memset(stats, 0, sizeof(*stats));
/*
* Each accounting subsystem adds calls to its functions to
@ -209,17 +195,27 @@ static int fill_pid(pid_t pid, struct task_struct *tsk,
/* fill in extended acct fields */
xacct_add_tsk(stats, tsk);
/* Define err: label here if needed */
put_task_struct(tsk);
return rc;
}
static int fill_tgid(pid_t tgid, struct task_struct *first,
struct taskstats *stats)
static int fill_stats_for_pid(pid_t pid, struct taskstats *stats)
{
struct task_struct *tsk;
rcu_read_lock();
tsk = find_task_by_vpid(pid);
if (tsk)
get_task_struct(tsk);
rcu_read_unlock();
if (!tsk)
return -ESRCH;
fill_stats(tsk, stats);
put_task_struct(tsk);
return 0;
}
static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats)
{
struct task_struct *tsk, *first;
unsigned long flags;
int rc = -ESRCH;
@ -228,8 +224,7 @@ static int fill_tgid(pid_t tgid, struct task_struct *first,
* leaders who are already counted with the dead tasks
*/
rcu_read_lock();
if (!first)
first = find_task_by_vpid(tgid);
first = find_task_by_vpid(tgid);
if (!first || !lock_task_sighand(first, &flags))
goto out;
@ -268,7 +263,6 @@ out:
return rc;
}
static void fill_tgid_exit(struct task_struct *tsk)
{
unsigned long flags;
@ -483,7 +477,7 @@ static int cmd_attr_pid(struct genl_info *info)
if (!stats)
goto err;
rc = fill_pid(pid, NULL, stats);
rc = fill_stats_for_pid(pid, stats);
if (rc < 0)
goto err;
return send_reply(rep_skb, info);
@ -513,7 +507,7 @@ static int cmd_attr_tgid(struct genl_info *info)
if (!stats)
goto err;
rc = fill_tgid(tgid, NULL, stats);
rc = fill_stats_for_tgid(tgid, stats);
if (rc < 0)
goto err;
return send_reply(rep_skb, info);
@ -599,9 +593,7 @@ void taskstats_exit(struct task_struct *tsk, int group_dead)
if (!stats)
goto err;
rc = fill_pid(-1, tsk, stats);
if (rc < 0)
goto err;
fill_stats(tsk, stats);
/*
* Doesn't matter if tsk is the leader or the last group member leaving