The patch titled Subject: checkpatch: emit fewer kmalloc_array/kcalloc conversion warnings has been added to the -mm tree. Its filename is checkpatch-emit-fewer-kmalloc_array-kcalloc-conversion-warnings.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/checkpatch-emit-fewer-kmalloc_array-kcalloc-conversion-warnings.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/checkpatch-emit-fewer-kmalloc_array-kcalloc-conversion-warnings.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Joe Perches <joe@xxxxxxxxxxx> Subject: checkpatch: emit fewer kmalloc_array/kcalloc conversion warnings Avoid matching allocs that appear to be known small multiplications of a sizeof with a constant because gcc as of 4.8 cannot optimize the code in a calloc() exactly the same way as an alloc(). Look for numeric constants or what appear to be upper case only macro #defines. Signed-off-by: Joe Perches <joe@xxxxxxxxxxx> Reported-by: Theodore Ts'o <tytso@xxxxxxx> Original-patch-by: Fabian Frederick <fabf@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- scripts/checkpatch.pl | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff -puN scripts/checkpatch.pl~checkpatch-emit-fewer-kmalloc_array-kcalloc-conversion-warnings scripts/checkpatch.pl --- a/scripts/checkpatch.pl~checkpatch-emit-fewer-kmalloc_array-kcalloc-conversion-warnings +++ a/scripts/checkpatch.pl @@ -4495,22 +4495,23 @@ sub process { # check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc if ($^V && $^V ge 5.10.0 && - $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/) { + $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)\s*,/) { my $oldfunc = $3; my $a1 = $4; my $a2 = $10; my $newfunc = "kmalloc_array"; $newfunc = "kcalloc" if ($oldfunc eq "kzalloc"); - if ($a1 =~ /^sizeof\s*\S/ || $a2 =~ /^sizeof\s*\S/) { + my $r1 = $a1; + my $r2 = $a2; + if ($a1 =~ /^sizeof\s*\S/) { + $r1 = $a2; + $r2 = $a1; + } + if ($r1 !~ /^sizeof\b/ && $r2 =~ /^sizeof\s*\S/ && + !($r1 =~ /^$Constant$/ || $r1 =~ /^[A-Z_][A-Z0-9_]*$/)) { if (WARN("ALLOC_WITH_MULTIPLY", "Prefer $newfunc over $oldfunc with multiply\n" . $herecurr) && $fix) { - my $r1 = $a1; - my $r2 = $a2; - if ($a1 =~ /^sizeof\s*\S/) { - $r1 = $a2; - $r2 = $a1; - } $fixed[$linenr - 1] =~ s/\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/$1 . ' = ' . "$newfunc(" . trim($r1) . ', ' . trim($r2)/e; } _ Patches currently in -mm which might be from joe@xxxxxxxxxxx are checkpatch-check-git-commit-descriptions.patch fs-squashfs-file_directc-replace-countsize-kmalloc-by-kmalloc_array.patch fs-asus_atk0110-fix-define_simple_attribute-semicolon-definition-and-use.patch printk-make-dynamic-kernel-ring-buffer-alignment-explicit.patch printk-move-power-of-2-practice-of-ring-buffer-size-to-a-helper.patch printk-make-dynamic-units-clear-for-the-kernel-ring-buffer.patch printk-allow-increasing-the-ring-buffer-depending-on-the-number-of-cpus.patch printk-tweak-do_syslog-to-match-comments.patch maintainers-remove-two-ancient-eata-sections.patch mm-utilc-add-kstrimdup.patch kernelh-remove-deprecated-pack_hex_byte.patch checkpatch-attempt-to-find-unnecessary-out-of-memory-messages.patch checkpatch-warn-on-unnecessary-else-after-return-or-break.patch checkpatch-fix-complex-macro-false-positive-for-escaped-constant-char.patch checkpatch-fix-function-pointers-in-blank-line-needed-after-declarations-test.patch checkpatch-ignore-email-headers-better.patch checkpatchpl-also-suggest-else-if-when-if-follows-brace.patch checkpatch-add-test-for-blank-lines-after-function-struct-union-enum.patch checkpatch-add-test-for-blank-lines-after-function-struct-union-enum-declarations.patch checkpatch-add-a-multiple-blank-lines-test.patch checkpatch-change-blank-line-after-declaration-type-to-line_spacing.patch checkpatch-quiet-kconfig-help-message-checking.patch checkpatch-warn-on-unnecessary-parentheses-around-references-of-foo-bar.patch checkpatch-allow-multiple-const-types.patch checkpatch-improve-no-space-after-cast-test.patch checkpatch-emit-fewer-kmalloc_array-kcalloc-conversion-warnings.patch fs-isofs-logging-clean-up.patch proc-constify-seq_operations.patch sysctl-remove-now-unused-typedef-ctl_table.patch sysctl-remove-now-unused-typedef-ctl_table-fix.patch adfs-add-__printf-verification-fix-format-argument-mismatches.patch fs-qnx6-convert-printk-to-pr_foo.patch fs-qnx6-use-pr_fmt-and-__func__-in-logging.patch fs-qnx6-update-debugging-to-current-functions.patch scripts-coccinelle-free-add-null-test-before-freeing-functions.patch linux-next.patch pci-dma-compat-add-pci_zalloc_consistent-helper.patch atm-use-pci_zalloc_consistent.patch block-use-pci_zalloc_consistent.patch crypto-use-pci_zalloc_consistent.patch infiniband-use-pci_zalloc_consistent.patch i810-use-pci_zalloc_consistent.patch media-use-pci_zalloc_consistent.patch amd-use-pci_zalloc_consistent.patch atl1e-use-pci_zalloc_consistent.patch enic-use-pci_zalloc_consistent.patch sky2-use-pci_zalloc_consistent.patch micrel-use-pci_zalloc_consistent.patch qlogic-use-pci_zalloc_consistent.patch irda-use-pci_zalloc_consistent.patch ipw2100-use-pci_zalloc_consistent.patch mwl8k-use-pci_zalloc_consistent.patch rtl818x-use-pci_zalloc_consistent.patch rtlwifi-use-pci_zalloc_consistent.patch scsi-use-pci_zalloc_consistent.patch staging-use-pci_zalloc_consistent.patch synclink_gt-use-pci_zalloc_consistent.patch vme-bridges-use-pci_zalloc_consistent.patch amd-neaten-and-remove-unnecessary-oom-messages.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html