Re: Memory leaks in SMP MIPS linux 2.4.9?

[Ralf Baechle <ralf@oss.sgi.com>]

On Tue, Nov 27, 2001 at 05:09:00PM -0800, Krishna Kondaka wrote:

> I suspect that there are some memory leaks in the SMP MIPS linux 2.4.9.
> I would like to know if any one found the root cause and fixed them.

See patch below for fix.

> 	I just ran the script for 3 hours are here is the diff between
> 	the out put of /proc/meminfo and /proc/slabinfo before and
> 	after the test run ( lines with "<" are before the test and
> 	lines with ">" are after the test)

(Try diff -u which generates much more human readable output.)

> 	When I did some investigation, it looked like d_lookup() is
> 	not finding /proc/meminfo and /proc/slabinfo in the dcache and
> 	it is doing d_alloc() to add these to the cache every time
> 	cat /proc/meminfo or cat /proc/slabinfo is done. This looked odd
> 	and I ran the same script on x86 based linux (running 2.4.2) and
> 	I did not see MemFree (or any other caches) changing after the
> 	test was run for an hour. I am not sure how this is architecture
> 	dependent.

These caches essentially keep growing until you run out of memory which
is when they'll be freed.

  Ralf

--- linux.orig/include/asm-mips/mmu_context.h.orig	Wed Nov 28 14:45:19 2001
+++ linux/include/asm-mips/mmu_context.h	Wed Nov 28 14:47:37 2001
@@ -109,7 +109,10 @@
  */
 extern inline void destroy_context(struct mm_struct *mm)
 {
-	/* Nothing to do.  */
+#ifdef CONFIG_SMP
+	if (mm->context)
+		kfree((void *)mm->context);
+#endif
 }
 
 /*