linux-kernel - [PATCH v5 2/3] lib/lzo: 64-bit CTZ on arm64

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]

Date:   Tue, 5 Feb 2019 14:20:07 +0000
From:   Dave Rodgman <dave.rodgman@....com>
To:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Matt Sealey <Matt.Sealey@....com>,
        Dave Rodgman <dave.rodgman@....com>,
        "davem@...emloft.net" <davem@...emloft.net>,
        "gregkh@...uxfoundation.org" <gregkh@...uxfoundation.org>,
        "herbert@...dor.apana.org.au" <herbert@...dor.apana.org.au>,
        "markus@...rhumer.com" <markus@...rhumer.com>,
        "minchan@...nel.org" <minchan@...nel.org>,
        "nitingupta910@...il.com" <nitingupta910@...il.com>,
        "rpurdie@...nedhand.com" <rpurdie@...nedhand.com>,
        "sergey.senozhatsky.work@...il.com" 
        <sergey.senozhatsky.work@...il.com>,
        "sonnyrao@...gle.com" <sonnyrao@...gle.com>,
        "akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
        "sfr@...b.auug.org.au" <sfr@...b.auug.org.au>
CC:     nd <nd@....com>
Subject: [PATCH v5 2/3] lib/lzo: 64-bit CTZ on arm64

From: Matt Sealey <matt.sealey@....com>

LZO leaves some performance on the table by not realising that arm64 can
optimize count-trailing-zeros bit operations.

Add CONFIG_ARM64 to the checked definitions alongside CONFIG_X86_64 to
enable the use of rbit/clz instructions on full 64-bit quantities.

Link: http://lkml.kernel.org/r/20181127161913.23863-5-dave.rodgman@arm.com
Signed-off-by: Matt Sealey <matt.sealey@....com>
Signed-off-by: Dave Rodgman <dave.rodgman@....com>
Cc: David S. Miller <davem@...emloft.net>
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc: Herbert Xu <herbert@...dor.apana.org.au>
Cc: Markus F.X.J. Oberhumer <markus@...rhumer.com>
Cc: Minchan Kim <minchan@...nel.org>
Cc: Nitin Gupta <nitingupta910@...il.com>
Cc: Richard Purdie <rpurdie@...nedhand.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@...il.com>
Cc: Sonny Rao <sonnyrao@...gle.com>
Signed-off-by: Andrew Morton <akpm@...ux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@...b.auug.org.au>
---
 lib/lzo/lzodefs.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/lzo/lzodefs.h b/lib/lzo/lzodefs.h
index 497f9c9f03a8..00d1080155e4 100644
--- a/lib/lzo/lzodefs.h
+++ b/lib/lzo/lzodefs.h
@@ -25,7 +25,7 @@
 
 #if defined(__BIG_ENDIAN) && defined(__LITTLE_ENDIAN)
 #error "conflicting endian definitions"
-#elif defined(CONFIG_X86_64)
+#elif defined(CONFIG_X86_64) || defined(CONFIG_ARM64)
 #define LZO_USE_CTZ64	1
 #define LZO_USE_CTZ32	1
 #elif defined(CONFIG_X86) || defined(CONFIG_PPC)
-- 
2.17.1