linux-kernel - [PATCH 11/17] powerpc: Implement arch_xor_unlock_is_negative

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20230915183707.2707298-12-willy@infradead.org>
Date:   Fri, 15 Sep 2023 19:37:01 +0100
From:   "Matthew Wilcox (Oracle)" <willy@...radead.org>
To:     linux-kernel@...r.kernel.org
Cc:     "Matthew Wilcox (Oracle)" <willy@...radead.org>,
        linux-fsdevel@...r.kernel.org, linux-arch@...r.kernel.org,
        torvalds@...ux-foundation.org, Nicholas Piggin <npiggin@...il.com>
Subject: [PATCH 11/17] powerpc: Implement arch_xor_unlock_is_negative_byte on 32-bit

Simply remove the ifdef.  The assembly is identical to that in the
non-optimised case of test_and_clear_bits() on PPC32, and it's not clear
to me how the PPC32 optimisation works, nor whether it would work for
arch_xor_unlock_is_negative_byte().  If that optimisation would work,
someone can implement it later, but this is more efficient than the
implementation in filemap.c.

Signed-off-by: Matthew Wilcox (Oracle) <willy@...radead.org>
---
 arch/powerpc/include/asm/bitops.h | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arch/powerpc/include/asm/bitops.h b/arch/powerpc/include/asm/bitops.h
index 40cc3ded60cb..671ecc6711e3 100644
--- a/arch/powerpc/include/asm/bitops.h
+++ b/arch/powerpc/include/asm/bitops.h
@@ -233,7 +233,6 @@ static inline int arch_test_and_change_bit(unsigned long nr,
 	return test_and_change_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0;
 }
 
-#ifdef CONFIG_PPC64
 static inline bool arch_xor_unlock_is_negative_byte(unsigned long mask,
 		volatile unsigned long *p)
 {
@@ -251,11 +250,8 @@ static inline bool arch_xor_unlock_is_negative_byte(unsigned long mask,
 
 	return (old & BIT_MASK(7)) != 0;
 }
-
 #define arch_xor_unlock_is_negative_byte arch_xor_unlock_is_negative_byte
 
-#endif /* CONFIG_PPC64 */
-
 #include <asm-generic/bitops/non-atomic.h>
 
 static inline void arch___clear_bit_unlock(int nr, volatile unsigned long *addr)
-- 
2.40.1