latencytop: change /proc task_struct access method

Change getting task_struct by get_proc_task() at read or write time,
and returns -ESRCH if get_proc_task() returns NULL.
This is same behavior as other /proc files.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Hiroshi Shimamoto 2008-02-20 16:53:29 -08:00 committed by Ingo Molnar
parent d6643d12cb
commit 13d77c37ca

View File

@ -314,9 +314,12 @@ static int proc_pid_schedstat(struct task_struct *task, char *buffer)
static int lstats_show_proc(struct seq_file *m, void *v)
{
int i;
struct task_struct *task = m->private;
seq_puts(m, "Latency Top version : v0.1\n");
struct inode *inode = m->private;
struct task_struct *task = get_proc_task(inode);
if (!task)
return -ESRCH;
seq_puts(m, "Latency Top version : v0.1\n");
for (i = 0; i < 32; i++) {
if (task->latency_record[i].backtrace[0]) {
int q;
@ -341,43 +344,24 @@ static int lstats_show_proc(struct seq_file *m, void *v)
}
}
put_task_struct(task);
return 0;
}
static int lstats_open(struct inode *inode, struct file *file)
{
int ret;
struct seq_file *m;
struct task_struct *task = get_proc_task(inode);
if (!task)
return -ENOENT;
ret = single_open(file, lstats_show_proc, NULL);
if (!ret) {
m = file->private_data;
m->private = task;
}
return ret;
}
static int lstats_release(struct inode *inode, struct file *file)
{
struct seq_file *m = file->private_data;
struct task_struct *task = m->private;
put_task_struct(task);
return single_release(inode, file);
return single_open(file, lstats_show_proc, inode);
}
static ssize_t lstats_write(struct file *file, const char __user *buf,
size_t count, loff_t *offs)
{
struct seq_file *m;
struct task_struct *task;
struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
m = file->private_data;
task = m->private;
if (!task)
return -ESRCH;
clear_all_latency_tracing(task);
put_task_struct(task);
return count;
}
@ -387,7 +371,7 @@ static const struct file_operations proc_lstats_operations = {
.read = seq_read,
.write = lstats_write,
.llseek = seq_lseek,
.release = lstats_release,
.release = single_release,
};
#endif