locking/pvqspinlock: Robustify init_qspinlock_stat()

Specifically around the debugfs file creation calls,
I have no idea if they could ever possibly fail, but
this is core code (debug aside) so lets at least
check the return value and inform anything fishy.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Waiman Long <Waiman.Long@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160420041725.GC3472@linux-uzut.site
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Davidlohr Bueso 2016-04-19 21:17:25 -07:00 committed by Ingo Molnar
parent dc209a3fd7
commit b96bbdde19
1 changed files with 14 additions and 8 deletions

View File

@ -212,10 +212,8 @@ static int __init init_qspinlock_stat(void)
struct dentry *d_qstat = debugfs_create_dir("qlockstat", NULL);
int i;
if (!d_qstat) {
pr_warn("Could not create 'qlockstat' debugfs directory\n");
return 0;
}
if (!d_qstat)
goto out;
/*
* Create the debugfs files
@ -225,12 +223,20 @@ static int __init init_qspinlock_stat(void)
* performance.
*/
for (i = 0; i < qstat_num; i++)
debugfs_create_file(qstat_names[i], 0400, d_qstat,
(void *)(long)i, &fops_qstat);
if (!debugfs_create_file(qstat_names[i], 0400, d_qstat,
(void *)(long)i, &fops_qstat))
goto fail_undo;
if (!debugfs_create_file(qstat_names[qstat_reset_cnts], 0200, d_qstat,
(void *)(long)qstat_reset_cnts, &fops_qstat))
goto fail_undo;
debugfs_create_file(qstat_names[qstat_reset_cnts], 0200, d_qstat,
(void *)(long)qstat_reset_cnts, &fops_qstat);
return 0;
fail_undo:
debugfs_remove_recursive(d_qstat);
out:
pr_warn("Could not create 'qlockstat' debugfs entries\n");
return -ENOMEM;
}
fs_initcall(init_qspinlock_stat);