checkpatch.pl: add "prefer __packed" check

There's a __packed #define for __attribute__((packed)).  Add a checkpatch
to tell people about it.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index fd9560e..4c0383d 100755 (executable)
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2743,6 +2743,11 @@ sub process {
                        WARN("plain inline is preferred over $1\n" . $herecurr);
                }
 
+# Check for __attribute__ packed, prefer __packed
+               if ($line =~ /\b__attribute__\s*\(\s*\(.*\bpacked\b/) {
+                       WARN("__packed is preferred over __attribute__((packed))\n" . $herecurr);
+               }
+
 # check for sizeof(&)
                if ($line =~ /\bsizeof\s*\(\s*\&/) {
                        WARN("sizeof(& should be avoided\n" . $herecurr);