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| author | Denis Efremov <efremov@linux.com> | 2019-09-25 16:49:25 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-09-25 17:51:42 -0700 |
| commit | de3f186f87cf15bed8d13fedafb5bcad0167fc6d (patch) | |
| tree | a3207fcc15d1708ff81182e1cc77e50feb4254b7 /scripts | |
| parent | c7cc8d77316b4386622b2dbd29de800df7b05099 (diff) | |
| download | linux-de3f186f87cf15bed8d13fedafb5bcad0167fc6d.tar.gz linux-de3f186f87cf15bed8d13fedafb5bcad0167fc6d.tar.bz2 linux-de3f186f87cf15bed8d13fedafb5bcad0167fc6d.zip | |
checkpatch: check for nested (un)?likely() calls
IS_ERR(), IS_ERR_OR_NULL(), IS_ERR_VALUE() and WARN*() already contain
unlikely() optimization internally. Thus, there is no point in calling
these functions and defines under likely()/unlikely().
This check is based on the coccinelle rule developed by Enrico Weigelt
https://lore.kernel.org/lkml/1559767582-11081-1-git-send-email-info@metux.net/
Link: http://lkml.kernel.org/r/20190829165025.15750-1-efremov@linux.com
Signed-off-by: Denis Efremov <efremov@linux.com>
Cc: Joe Perches <joe@perches.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Anton Altaparmakov <anton@tuxera.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Boris Pismenny <borisp@mellanox.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Denis Efremov <efremov@linux.com>
Cc: Dennis Dalessandro <dennis.dalessandro@intel.com>
Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Mike Marciniszyn <mike.marciniszyn@intel.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Sean Paul <sean@poorly.run>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'scripts')
| -rwxr-xr-x | scripts/checkpatch.pl | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 4eb355d8ae73..6fcc66afb088 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -6507,6 +6507,12 @@ sub process { "Using $1 should generally have parentheses around the comparison\n" . $herecurr); } +# nested likely/unlikely calls + if ($line =~ /\b(?:(?:un)?likely)\s*\(\s*!?\s*(IS_ERR(?:_OR_NULL|_VALUE)?|WARN)/) { + WARN("LIKELY_MISUSE", + "nested (un)?likely() calls, $1 already uses unlikely() internally\n" . $herecurr); + } + # whine mightly about in_atomic if ($line =~ /\bin_atomic\s*\(/) { if ($realfile =~ m@^drivers/@) { |