[tip:x86/urgent] x86/kconfig: Disable CONFIG_GENERIC_HWEIGHT and remove __HAVE_ARCH_SW_HWEIGHT

From: tip-bot for Masahiro Yamada
Date: Mon May 13 2019 - 05:12:28 EST


Commit-ID: 409ca45526a428620d8efb362ccfd4b1e6b80642
Gitweb: https://git.kernel.org/tip/409ca45526a428620d8efb362ccfd4b1e6b80642
Author: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
AuthorDate: Sun, 12 May 2019 21:52:01 +0900
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Mon, 13 May 2019 11:07:33 +0200

x86/kconfig: Disable CONFIG_GENERIC_HWEIGHT and remove __HAVE_ARCH_SW_HWEIGHT

Remove an unnecessary arch complication:

arch/x86/include/asm/arch_hweight.h uses __sw_hweight{32,64} as
alternatives, and they are implemented in arch/x86/lib/hweight.S

x86 does not rely on the generic C implementation lib/hweight.c
at all, so CONFIG_GENERIC_HWEIGHT should be disabled.

__HAVE_ARCH_SW_HWEIGHT is not necessary either.

No change in functionality intended.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Uros Bizjak <ubizjak@xxxxxxxxx>
Link: http://lkml.kernel.org/r/1557665521-17570-1-git-send-email-yamada.masahiro@xxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/Kconfig | 3 ---
arch/x86/include/asm/arch_hweight.h | 2 --
lib/hweight.c | 4 ----
3 files changed, 9 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0a3cc347143f..de071d7e67b6 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -261,9 +261,6 @@ config GENERIC_BUG
config GENERIC_BUG_RELATIVE_POINTERS
bool

-config GENERIC_HWEIGHT
- def_bool y
-
config ARCH_MAY_HAVE_PC_FDC
def_bool y
depends on ISA_DMA_API
diff --git a/arch/x86/include/asm/arch_hweight.h b/arch/x86/include/asm/arch_hweight.h
index fc0693569f7a..ba88edd0d58b 100644
--- a/arch/x86/include/asm/arch_hweight.h
+++ b/arch/x86/include/asm/arch_hweight.h
@@ -12,8 +12,6 @@
#define REG_OUT "a"
#endif

-#define __HAVE_ARCH_SW_HWEIGHT
-
static __always_inline unsigned int __arch_hweight32(unsigned int w)
{
unsigned int res;
diff --git a/lib/hweight.c b/lib/hweight.c
index 7660d88fd496..c94586b62551 100644
--- a/lib/hweight.c
+++ b/lib/hweight.c
@@ -10,7 +10,6 @@
* The Hamming Weight of a number is the total number of bits set in it.
*/

-#ifndef __HAVE_ARCH_SW_HWEIGHT
unsigned int __sw_hweight32(unsigned int w)
{
#ifdef CONFIG_ARCH_HAS_FAST_MULTIPLIER
@@ -27,7 +26,6 @@ unsigned int __sw_hweight32(unsigned int w)
#endif
}
EXPORT_SYMBOL(__sw_hweight32);
-#endif

unsigned int __sw_hweight16(unsigned int w)
{
@@ -46,7 +44,6 @@ unsigned int __sw_hweight8(unsigned int w)
}
EXPORT_SYMBOL(__sw_hweight8);

-#ifndef __HAVE_ARCH_SW_HWEIGHT
unsigned long __sw_hweight64(__u64 w)
{
#if BITS_PER_LONG == 32
@@ -69,4 +66,3 @@ unsigned long __sw_hweight64(__u64 w)
#endif
}
EXPORT_SYMBOL(__sw_hweight64);
-#endif