From: Dwaipayan Ray <dwaipayanray1@xxxxxxxxx> Subject: checkpatch: extend attributes check to handle more patterns It is generally preferred that the macros from include/linux/compiler_attributes.h are used, unless there is a reason not to. checkpatch currently checks __attribute__ for each of packed, aligned, section, printf, scanf, and weak. Other declarations in compiler_attributes.h are not handled. Add a generic test to check the presence of such attributes. Some attributes require more specific handling and are kept separate. Also add fixes to the generic attributes check to substitute the correct conversions. New attributes which are now handled are: __always_inline__ __assume_aligned__(a, ## __VA_ARGS__) __cold__ __const__ __copy__(symbol) __designated_init__ __externally_visible__ __gnu_inline__ __malloc__ __mode__(x) __no_caller_saved_registers__ __noclone__ __noinline__ __nonstring__ __noreturn__ __pure__ __unused__ __used__ Declarations which contain multiple attributes like __attribute__((__packed__, __cold__)) are also handled except when proper conversions for one or more attributes of the list cannot be determined. Link: https://lore.kernel.org/linux-kernel-mentees/3ec15b41754b01666d94b76ce51b9832c2dd577a.camel@xxxxxxxxxxx/ Link: https://lkml.kernel.org/r/20201025193103.23223-1-dwaipayanray1@xxxxxxxxx Signed-off-by: Dwaipayan Ray <dwaipayanray1@xxxxxxxxx> Suggested-by: Joe Perches <joe@xxxxxxxxxxx> Acked-by: Joe Perches <joe@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- scripts/checkpatch.pl | 109 ++++++++++++++++++++++++++-------------- 1 file changed, 71 insertions(+), 38 deletions(-) --- a/scripts/checkpatch.pl~checkpatch-extend-attributes-check-to-handle-more-patterns +++ a/scripts/checkpatch.pl @@ -6187,50 +6187,83 @@ sub process { } } -# Check for __attribute__ packed, prefer __packed +# Check for compiler attributes if ($realfile !~ m@\binclude/uapi/@ && - $line =~ /\b__attribute__\s*\(\s*\(.*\bpacked\b/) { - WARN("PREFER_PACKED", - "__packed is preferred over __attribute__((packed))\n" . $herecurr); - } - -# Check for __attribute__ aligned, prefer __aligned - if ($realfile !~ m@\binclude/uapi/@ && - $line =~ /\b__attribute__\s*\(\s*\(.*aligned/) { - WARN("PREFER_ALIGNED", - "__aligned(size) is preferred over __attribute__((aligned(size)))\n" . $herecurr); - } - -# Check for __attribute__ section, prefer __section - if ($realfile !~ m@\binclude/uapi/@ && - $line =~ /\b__attribute__\s*\(\s*\(.*_*section_*\s*\(\s*("[^"]*")/) { - my $old = substr($rawline, $-[1], $+[1] - $-[1]); - my $new = substr($old, 1, -1); - if (WARN("PREFER_SECTION", - "__section($new) is preferred over __attribute__((section($old)))\n" . $herecurr) && - $fix) { - $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*_*section_*\s*\(\s*\Q$old\E\s*\)\s*\)\s*\)/__section($new)/; + $rawline =~ /\b__attribute__\s*\(\s*($balanced_parens)\s*\)/) { + my $attr = $1; + $attr =~ s/\s*\(\s*(.*)\)\s*/$1/; + + my %attr_list = ( + "aligned" => "__aligned", + "always_inline" => "__always_inline", + "assume_aligned" => "__assume_aligned", + "cold" => "__cold", + "const" => "__attribute_const__", + "copy" => "__copy", + "designated_init" => "__designated_init", + "externally_visible" => "__visible", + "format" => "printf|scanf", + "gnu_inline" => "__gnu_inline", + "malloc" => "__malloc", + "mode" => "__mode", + "no_caller_saved_registers" => "__no_caller_saved_registers", + "noclone" => "__noclone", + "noinline" => "noinline", + "nonstring" => "__nonstring", + "noreturn" => "__noreturn", + "packed" => "__packed", + "pure" => "__pure", + "used" => "__used" + ); + + my @conv_array = (); + my $conv_possible = 1; + + while ($attr =~ /\s*(\w+)\s*(${balanced_parens})?/g) { + my $curr_attr = $1; + my $params = ''; + $params = $2 if defined($2); + $curr_attr =~ s/^[\s_]+|[\s_]+$//g; + + if (exists($attr_list{$curr_attr})) { + if ($curr_attr eq "format" && $params) { + $params =~ /^\s*\(\s*(\w+)\s*,\s*(.*)/; + push(@conv_array, "__$1\($2"); + } else { + my $new = $attr_list{$curr_attr}; + push(@conv_array, "$new$params"); + } + } else { + $conv_possible = 0; + last; + } } - } -# Check for __attribute__ format(printf, prefer __printf - if ($realfile !~ m@\binclude/uapi/@ && - $line =~ /\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf/) { - if (WARN("PREFER_PRINTF", - "__printf(string-index, first-to-check) is preferred over __attribute__((format(printf, string-index, first-to-check)))\n" . $herecurr) && - $fix) { - $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf\s*,\s*(.*)\)\s*\)\s*\)/"__printf(" . trim($1) . ")"/ex; + if (scalar @conv_array > 0 && $conv_possible == 1) { + my $replace = join(' ', @conv_array); + if (WARN("PREFER_DEFINED_ATTRIBUTE_MACRO", + "$replace is preferred over __attribute__(($attr))\n" . $herecurr) && + $fix) { + $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*\Q$attr\E\s*\)\s*\)/$replace/; + $fixed[$fixlinenr] =~ s/\}\Q$replace\E/} $replace/; + } + } + # Check for __attribute__ section, prefer __section + if ($attr =~ /^_*section_*\s*\(\s*("[^"]*")/) { + my $old = substr($attr, $-[1], $+[1] - $-[1]); + my $new = substr($old, 1, -1); + if (WARN("PREFER_DEFINED_ATTRIBUTE_MACRO", + "__section($new) is preferred over __attribute__((section($old)))\n" . $herecurr) && + $fix) { + $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*_*section_*\s*\(\s*\Q$old\E\s*\)\s*\)\s*\)/__section($new)/; + } } - } -# Check for __attribute__ format(scanf, prefer __scanf - if ($realfile !~ m@\binclude/uapi/@ && - $line =~ /\b__attribute__\s*\(\s*\(\s*format\s*\(\s*scanf\b/) { - if (WARN("PREFER_SCANF", - "__scanf(string-index, first-to-check) is preferred over __attribute__((format(scanf, string-index, first-to-check)))\n" . $herecurr) && - $fix) { - $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*scanf\s*,\s*(.*)\)\s*\)\s*\)/"__scanf(" . trim($1) . ")"/ex; + # Check for __attribute__ unused, prefer __always_unused or __maybe_unused + if ($attr =~ /^_*unused/) { + WARN("PREFER_DEFINED_ATTRIBUTE_MACRO", + "__always_unused or __maybe_unused is preferred over __attribute__((__unused__))\n" . $herecurr); } } _
