mm: alloc_contig_range: demote pages busy message from warn to info

Having test_pages_isolated failure message as a warning confuses users
into thinking that it is more serious than it really is.  In reality, if
called via CMA, allocation will be retried so a single
test_pages_isolated failure does not prevent allocation from succeeding.

Demote the warning message to an info message and reformat it such that
the text "failed" does not appear and instead a less worrying "PFNS
busy" is used.

This message is trivially reproducible on a 10GB x86 machine on 3.16.y
kernels configured with CONFIG_DMA_CMA.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 3 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index fd11b913779e..181dc593962b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6397,13 +6397,12 @@ int alloc_contig_range(unsigned long start, unsigned long end,
 
         /* Make sure the range is really isolated. */
         if (test_pages_isolated(outer_start, end, false)) {
-                pr_warn("alloc_contig_range test_pages_isolated(%lx, %lx) failed\n",
-                       outer_start, end);
+                pr_info("%s: [%lx, %lx) PFNs busy\n",
+                        __func__, outer_start, end);
                 ret = -EBUSY;
                 goto done;
         }
 
-
         /* Grab isolated pages from freelists. */
         outer_end = isolate_freepages_range(&cc, outer_start, end);
         if (!outer_end) {