Hi, David,
On Sat, Oct 2, 2021 at 4:20 AM David Gow davidgow@google.com wrote:
On Mon, Sep 27, 2021 at 6:33 AM Isabella Basso isabellabdoamaral@usp.br wrote:
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.ne...
Changes since v1:
- As suggested by David Gow:
- Reword commit message.
Maybe move this changelog to below the "---", so it doesn't show up in the final commit message?
Oh, okay! Thanks for pointing that out :) I didn't quite know how I should put these.
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 isabellabdoamaral@usp.br
This looks sensible enough to me. Since no-one seems to be speaking up in architecture-specific hash_32()'s defence, let's get rid of it.
Reviewed-by: David Gow davidgow@google.com
Alright! Thanks for the review.
Cheers, -- Isabella B.
include/linux/hash.h | 5 +---- lib/test_hash.c | 24 +----------------------- tools/include/linux/hash.h | 5 +---- 3 files changed, 3 insertions(+), 31 deletions(-)
diff --git a/include/linux/hash.h b/include/linux/hash.h index ad6fa21d977b..38edaa08f862 100644 --- a/include/linux/hash.h +++ b/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); diff --git a/lib/test_hash.c b/lib/test_hash.c index 0ee40b4a56dd..d4b0cfdb0377 100644 --- a/lib/test_hash.c +++ b/lib/test_hash.c @@ -94,22 +94,7 @@ test_int_hash(unsigned long long h64, u32 hash_or[2][33]) pr_err("hash_32(%#x, %d) = %#x > %#x", h0, k, h1, m); return false; } -#ifdef HAVE_ARCH_HASH_32
h2 = hash_32_generic(h0, k);-#if HAVE_ARCH_HASH_32 == 1
if (h1 != h2) {pr_err("hash_32(%#x, %d) = %#x != hash_32_generic() "" = %#x", h0, k, h1, h2);return false;}-#else
if (h2 > m) {pr_err("hash_32_generic(%#x, %d) = %#x > %#x",h0, k, h1, m);return false;}-#endif -#endif
/* Test hash_64 */ hash_or[1][k] |= h1 = hash_64(h64, k); if (h1 > m) {@@ -227,13 +212,6 @@ test_hash_init(void) #else pr_info("__hash_32() has no arch implementation to test."); #endif -#ifdef HAVE_ARCH_HASH_32 -#if HAVE_ARCH_HASH_32 != 1
pr_info("hash_32() is arch-specific; not compared to generic.");-#endif -#else
pr_info("hash_32() has no arch implementation to test.");-#endif #ifdef HAVE_ARCH_HASH_64 #if HAVE_ARCH_HASH_64 != 1 pr_info("hash_64() is arch-specific; not compared to generic."); 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); -- 2.33.0