Commit 13d77c37 authored by Hiroshi Shimamoto's avatar Hiroshi Shimamoto Committed by Ingo Molnar
Browse files

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: default avatarHiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent d6643d12

fs/proc/base.c

+12 −28
Original line number Diff line number Diff line
@@ -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

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