checkpatch: Prefer seq_puts to seq_printf

Add a check for seq_printf use with a constant format without additional
arguments.  Suggest seq_puts instead.

Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 16 insertions, 0 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index a820249a3fce..b8b03aa52beb 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -628,6 +628,13 @@ sub sanitise_line {
         return $res;
 }
 
+sub get_quoted_string {
+        my ($line, $rawline) = @_;
+
+        return "" if ($line !~ m/(\"[X]+\")/g);
+        return substr($rawline, $-[0], $+[0] - $-[0]);
+}
+
 sub ctx_statement_block {
         my ($linenr, $remain, $off) = @_;
         my $line = $linenr - 1;
@@ -3373,6 +3380,15 @@ sub process {
                              "struct spinlock should be spinlock_t\n" . $herecurr);
                 }
 
+# check for seq_printf uses that could be seq_puts
+                if ($line =~ /\bseq_printf\s*\(/) {
+                        my $fmt = get_quoted_string($line, $rawline);
+                        if ($fmt !~ /[^\\]\%/) {
+                                WARN("PREFER_SEQ_PUTS",
+                                     "Prefer seq_puts to seq_printf\n" . $herecurr);
+                        }
+                }
+
 # Check for misused memsets
                 if ($^V && $^V ge 5.10.0 &&
                     defined $stat &&