mm: cma: improve pr_debug log in cma_release() 21/262721/2
authorCharan Teja Reddy <charante@codeaurora.org>
Tue, 15 Dec 2020 03:13:26 +0000 (19:13 -0800)
committerSeung-Woo Kim <sw0312.kim@samsung.com>
Thu, 19 Aug 2021 02:45:32 +0000 (02:45 +0000)
commit99eef1bd4a4f1d9a1351e68d54cebe86a38afe7c
treee24d09ce4879473e4e0d32921c314b33fdad6c8e
parent57dba3134e126db09c287597e6ac1e97d81d5ad3
mm: cma: improve pr_debug log in cma_release()

It is required to print 'count' of pages, along with the pages, passed to
cma_release to debug the cases of mismatched count value passed between
cma_alloc() and cma_release() from a code path.

As an example, consider the below scenario:

1) CMA pool size is 4MB and

2) User doing the erroneous step of allocating 2 pages but freeing 1
   page in a loop from this CMA pool.  The step 2 causes cma_alloc() to
   return NULL at one point of time because of -ENOMEM condition.

And the current pr_debug logs is not giving the info about these types of
allocation patterns because of count value not being printed in
cma_release().

We are printing the count value in the trace logs, just extend the same to
pr_debug logs too.

[akpm@linux-foundation.org: fix printk warning]

Link: https://lkml.kernel.org/r/1606318341-29521-1-git-send-email-charante@codeaurora.org
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
Reviewed-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Origin: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=b8ca396f984295ba09f25f6982f9abd0bb7f5a29
Signed-off-by: Ɓukasz Stelmach <l.stelmach@samsung.com>
Change-Id: Ic44cb49df247f690145a2d9dc8279aa94de4205f
mm/cma.c