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authorIsabella Basso <isabbasso@riseup.net>2022-01-20 05:09:02 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2022-01-20 09:52:54 +0300
commitfd0a1462405b087377e59b84e119fe7e2d08499a (patch)
tree9e66a7f2d69c34d16bc48183dab93477fbf702d1 /tools/include/linux/hash.h
parenta31f9336ed48317d61c2299d595ed14294ffe5f9 (diff)
downloadlinux-fd0a1462405b087377e59b84e119fe7e2d08499a.tar.xz
hash.h: remove unused define directive
Patch series "test_hash.c: refactor into KUnit", v3. We refactored the lib/test_hash.c file into KUnit as part of the student group LKCAMP [1] introductory hackathon for kernel development. This test was pointed to our group by Daniel Latypov [2], so its full conversion into a pure KUnit test was our goal in this patch series, but we ran into many problems relating to it not being split as unit tests, which complicated matters a bit, as the reasoning behind the original tests is quite cryptic for those unfamiliar with hash implementations. Some interesting developments we'd like to highlight are: - In patch 1/5 we noticed that there was an unused define directive that could be removed. - In patch 4/5 we noticed how stringhash and hash tests are all under the lib/test_hash.c file, which might cause some confusion, and we also broke those kernel config entries up. Overall KUnit developments have been made in the other patches in this series: In patches 2/5, 3/5 and 5/5 we refactored the lib/test_hash.c file so as to make it more compatible with the KUnit style, whilst preserving the original idea of the maintainer who designed it (i.e. George Spelvin), which might be undesirable for unit tests, but we assume it is enough for a first patch. This patch (of 5): Currently, there exist hash_32() and __hash_32() functions, which were introduced in a patch [1] targeting architecture specific optimizations. These functions can be overridden on a per-architecture basis to achieve such optimizations. They must set their corresponding define directive (HAVE_ARCH_HASH_32 and HAVE_ARCH__HASH_32, respectively) so that header files can deal with these overrides properly. As the supported 32-bit architectures that have their own hash function implementation (i.e. m68k, Microblaze, H8/300, pa-risc) have only been making use of the (more general) __hash_32() function (which only lacks a right shift operation when compared to the hash_32() function), remove the define directive corresponding to the arch-specific hash_32() implementation. [1] https://lore.kernel.org/lkml/20160525073311.5600.qmail@ns.sciencehorizons.net/ [akpm@linux-foundation.org: hash_32_generic() becomes hash_32()] Link: https://lkml.kernel.org/r/20211208183711.390454-1-isabbasso@riseup.net Link: https://lkml.kernel.org/r/20211208183711.390454-2-isabbasso@riseup.net Reviewed-by: David Gow <davidgow@google.com> Tested-by: David Gow <davidgow@google.com> Co-developed-by: Augusto Durães Camargo <augusto.duraes33@gmail.com> Signed-off-by: Augusto Durães Camargo <augusto.duraes33@gmail.com> Co-developed-by: Enzo Ferreira <ferreiraenzoa@gmail.com> Signed-off-by: Enzo Ferreira <ferreiraenzoa@gmail.com> Signed-off-by: Isabella Basso <isabbasso@riseup.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Daniel Latypov <dlatypov@google.com> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com> Cc: kernel test robot <lkp@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'tools/include/linux/hash.h')
-rw-r--r--tools/include/linux/hash.h5
1 files changed, 1 insertions, 4 deletions
diff --git a/tools/include/linux/hash.h b/tools/include/linux/hash.h
index ad6fa21d977b..38edaa08f862 100644
--- a/tools/include/linux/hash.h
+++ b/tools/include/linux/hash.h
@@ -62,10 +62,7 @@ static inline u32 __hash_32_generic(u32 val)
return val * GOLDEN_RATIO_32;
}
-#ifndef HAVE_ARCH_HASH_32
-#define hash_32 hash_32_generic
-#endif
-static inline u32 hash_32_generic(u32 val, unsigned int bits)
+static inline u32 hash_32(u32 val, unsigned int bits)
{
/* High bits are more random, so use them. */
return __hash_32(val) >> (32 - bits);