diff options
| author | Gregory Bean <gbean@codeaurora.org> | 2011-05-02 13:50:35 -0700 |
|---|---|---|
| committer | David Keitel <dkeitel@codeaurora.org> | 2016-03-23 20:51:43 -0700 |
| commit | 05379004cc48c1d9a2b2fd6ff4e518bd92355062 (patch) | |
| tree | 227f1f2fbb2fc829e5eb0f7b3a0517466158ce42 /scripts/checkpatch.pl | |
| parent | e446047078933394c3f2fb206f4991dbf2f7b27b (diff) | |
checkpatch: forbid implied-barrier I/O functions.
Forbid read[bwl], write[bwl], in[bwl], and out[bwl], as they
contain a 'stealth barrier' which can harm performance.
Developers are expected to call appropriate __raw_* or *_relaxed
APIs and manage barriers explicitly.
Change-Id: Ie4da221c91a0505917199db9e2fdb704c3e47d44
Signed-off-by: Gregory Bean <gbean@codeaurora.org>
(cherry picked from commit 032fd4ba09e195d9913c08f460130da9905936ef)
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
Diffstat (limited to 'scripts/checkpatch.pl')
| -rwxr-xr-x | scripts/checkpatch.pl | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 0367e22008d8..f59113732720 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -4930,6 +4930,26 @@ sub process { $herecurr); } +# read[bwl] & write[bwl] use too many barriers, use the _relaxed variants + if ($line =~ /\b((?:read|write)[bwl])\b/) { + ERROR("NON_RELAXED_IO", + "Use of $1 is deprecated: use $1_relaxed\n\t" . + "with appropriate memory barriers instead.\n" . + $herecurr); + } + +# likewise, in/out[bwl] should be __raw_read/write[bwl]... + if ($line =~ /\b((in|out)([bwl]))\b/) { + my ($all, $pref, $suf) = ($1, $2, $3); + $pref =~ s/in/read/; + $pref =~ s/out/write/; + ERROR("NON_RELAXED_IO", + "Use of $all is deprecated: use " . + "__raw_$pref$suf\n\t" . + "with appropriate memory barriers instead.\n" . + $herecurr); + } + # warn about #if 0 if ($line =~ /^.\s*\#\s*if\s+0\b/) { WARN("IF_0", |