Commit e29a70f1 authored by Joe Perches's avatar Joe Perches Committed by Linus Torvalds
Browse files

checkpatch: add some new alloc functions to various tests 

Many new generic allocation functions like the kvmalloc family have been
added recently to the kernel.

The allocation functions test now includes:

o kvmalloc and variants
o kstrdup_const
o kmemdup_nul
o dma_alloc_coherent
o alloc_skb and variants

Add a separate $allocFunctions variable to help make the allocation
functions test a bit more readable.

Miscellanea:

o Use $allocFunctions in the unnecessary OOM message test and
  add exclude uses with __GFP_NOWARN
o Use $allocFunctions in the unnecessary cast test
o Add the kvmalloc family to the preferred sizeof alloc style
  foo = kvmalloc(sizeof(*foo), ...)

Link: http://lkml.kernel.org/r/a5e60a2b93e10baf84af063f6c8e56402273105d.camel@perches.com


Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent fdf13693

scripts/checkpatch.pl

+15 −4
Original line number Diff line number Diff line
@@ -466,6 +466,16 @@ our $logFunctions = qr{(?x: 
	seq_vprintf|seq_printf|seq_puts

)};



our $allocFunctions = qr{(?x:

	(?:(?:devm_)?

		(?:kv|k|v)[czm]alloc(?:_node|_array)? |

		kstrdup(?:_const)? |

		kmemdup(?:_nul)?) |

	(?:\w+)?alloc_skb(?:ip_align)? |

				# dev_alloc_skb/netdev_alloc_skb, et al

	dma_alloc_coherent

)};



our $signature_tags = qr{(?xi:

	Signed-off-by:|

	Co-developed-by:|
@@ -5553,7 +5563,8 @@ sub process { 
			my ($s, $c) = ctx_statement_block($linenr - 3, $realcnt, 0);

#			print("line: <$line>\nprevline: <$prevline>\ns: <$s>\nc: <$c>\n\n\n");



			if ($s =~ /(?:^|\n)[ \+]\s*(?:$Type\s*)?\Q$testval\E\s*=\s*(?:\([^\)]*\)\s*)?\s*(?:devm_)?(?:[kv][czm]alloc(?:_node|_array)?\b|kstrdup|kmemdup|(?:dev_)?alloc_skb)/) {

			if ($s =~ /(?:^|\n)[ \+]\s*(?:$Type\s*)?\Q$testval\E\s*=\s*(?:\([^\)]*\)\s*)?\s*$allocFunctions\s*\(/ &&

			    $s !~ /\b__GFP_NOWARN\b/ ) {

				WARN("OOM_MESSAGE",

				     "Possible unnecessary 'out of memory' message\n" . $hereprev);

			}
@@ -6204,8 +6215,8 @@ sub process { 
			}

		}



# check for pointless casting of kmalloc return

		if ($line =~ /\*\s*\)\s*[kv][czm]alloc(_node){0,1}\b/) {

# check for pointless casting of alloc functions

		if ($line =~ /\*\s*\)\s*$allocFunctions\b/) {

			WARN("UNNECESSARY_CASTS",

			     "unnecessary cast may hide bugs, see http://c-faq.com/malloc/mallocnocast.html\n" . $herecurr);

		}
@@ -6213,7 +6224,7 @@ sub process { 
# alloc style

# p = alloc(sizeof(struct foo), ...) should be p = alloc(sizeof(*p), ...)

		if ($perl_version_ok &&

		    $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*([kv][mz]alloc(?:_node)?)\s*\(\s*(sizeof\s*\(\s*struct\s+$Lval\s*\))/) {

		    $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*((?:kv|k|v)[mz]alloc(?:_node)?)\s*\(\s*(sizeof\s*\(\s*struct\s+$Lval\s*\))/) {

			CHK("ALLOC_SIZEOF_STRUCT",

			    "Prefer $3(sizeof(*$1)...) over $3($4...)\n" . $herecurr);

		}

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