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| author |   Jesse Brandeburg <jesse.brandeburg@intel.com> | 2020-06-04 16:50:27 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2020-06-04 19:06:25 -0700 |
| commit | c348c16305280fe3e6c1186378f96c8634c149f9 (patch) | |
| tree | aa53fa861170b36756d7d1aa14c1ce4c00089da5 /lib/Makefile | |
| parent | lib/flex_proportions.c: cleanup __fprop_inc_percpu_max (diff) | |
| download | linux-dev-c348c16305280fe3e6c1186378f96c8634c149f9.tar.xz linux-dev-c348c16305280fe3e6c1186378f96c8634c149f9.zip | |
lib: make a test module with set/clear bit
Test some bit clears/sets to make sure assembly doesn't change, and that
the set_bit and clear_bit functions work and don't cause sparse warnings.
Instruct Kbuild to build this file with extra warning level -Wextra, to
catch new issues, and also doesn't hurt to build with C=1.
This was used to test changes to arch/x86/include/asm/bitops.h.
In particular, sparse (C=1) was very concerned when the last bit before a
natural boundary, like 7, or 31, was being tested, as this causes sign
extension (0xffffff7f) for instance when clearing bit 7.
Recommended usage:
make defconfig
scripts/config -m CONFIG_TEST_BITOPS
make modules_prepare
make C=1 W=1 lib/test_bitops.ko
objdump -S -d lib/test_bitops.ko
insmod lib/test_bitops.ko
rmmod lib/test_bitops.ko
<check dmesg>, there should be no compiler/sparse warnings and no
error messages in log.
Link: http://lkml.kernel.org/r/20200310221747.2848474-2-jesse.brandeburg@intel.com
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
CcL Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/Makefile')
| -rw-r--r-- | lib/Makefile | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/lib/Makefile b/lib/Makefile index 5adf8949a757..32f19b4d1d2a 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -56,6 +56,8 @@ obj-y += kstrtox.o obj-$(CONFIG_FIND_BIT_BENCHMARK) += find_bit_benchmark.o obj-$(CONFIG_TEST_BPF) += test_bpf.o obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o +obj-$(CONFIG_TEST_BITOPS) += test_bitops.o +CFLAGS_test_bitops.o += -Werror obj-$(CONFIG_TEST_SYSCTL) += test_sysctl.o obj-$(CONFIG_TEST_HASH) += test_hash.o test_siphash.o obj-$(CONFIG_TEST_IDA) += test_ida.o |