Re: [RFC] [PATCH] cpuset operations causes Badness at mm/slab.c:777 warning

[Srinivasa Ds <srinivasa@in.ibm.com>]

On Friday 01 June 2007 12:57:53 Srinivasa Ds wrote:

I have modified the patch little bit, Thanks Vatsa for input and hence 
resending it. Please let me know your comments on this.

Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com>

---
 kernel/cpuset.c |   10 ++++++++++
 1 file changed, 10 insertions(+)

Index: linux-2.6.22-rc3/kernel/cpuset.c
===================================================================
--- linux-2.6.22-rc3.orig/kernel/cpuset.c
+++ linux-2.6.22-rc3/kernel/cpuset.c
@@ -1741,6 +1741,13 @@ static int cpuset_tasks_open(struct inod
 	 * show up until sometime later on.
 	 */
 	npids = atomic_read(&cs->count);
+	if (!npids) {
+		ctr->buf = NULL;
+		ctr->bufsz = 0;
+		file->private_data = ctr;
+		return 0;
+	}
+
 	pidarray = kmalloc(npids * sizeof(pid_t), GFP_KERNEL);
 	if (!pidarray)
 		goto err1;
@@ -1772,6 +1779,9 @@ static ssize_t cpuset_tasks_read(struct 
 {
 	struct ctr_struct *ctr = file->private_data;
 
+	if (!ctr->buf)     /* No tasks in this cpuset */
+		return 0;
+
 	return simple_read_from_buffer(buf, nbytes, ppos, ctr->buf, ctr->bufsz);
 }