linux-kernel

Open Source and information security mailing list archives

Message-Id: <1204340690.15052.457.camel@pasglop>
Date:	Sat, 01 Mar 2008 14:04:50 +1100
From:	Benjamin Herrenschmidt <benh@...nel.crashing.org>
To:	Steven Rostedt <rostedt@...dmis.org>
Cc:	paulus@...ba.org, linuxppc-dev@...abs.org,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] add strncmp to PowerPC

On Fri, 2008-02-29 at 11:04 -0500, Steven Rostedt wrote:
> strncmp is defined in assembly for bootup, but it is not defined in the
> normal running kernel. This patch takes the strncmp code from the bootup
> and copies it to the kernel proper.
> 
> Signed-off-by: Steven Rostedt <srostedt@...hat.com>
> ---

Do we have any indication that it performs better than the C one ?

Ben.

>  arch/powerpc/kernel/ppc_ksyms.c |    1 +
>  arch/powerpc/lib/string.S       |   12 ++++++++++++
>  include/asm-powerpc/string.h    |    2 ++
>  3 files changed, 15 insertions(+)
> 
> Index: linux-sched-devel.git/arch/powerpc/kernel/ppc_ksyms.c
> ===================================================================
> --- linux-sched-devel.git.orig/arch/powerpc/kernel/ppc_ksyms.c	2008-02-27 14:01:38.000000000 -0800
> +++ linux-sched-devel.git/arch/powerpc/kernel/ppc_ksyms.c	2008-02-29 07:24:22.000000000 -0800
> @@ -78,6 +78,7 @@ EXPORT_SYMBOL(strncpy);
>  EXPORT_SYMBOL(strcat);
>  EXPORT_SYMBOL(strlen);
>  EXPORT_SYMBOL(strcmp);
> +EXPORT_SYMBOL(strncmp);
>  
>  EXPORT_SYMBOL(csum_partial);
>  EXPORT_SYMBOL(csum_partial_copy_generic);
> Index: linux-sched-devel.git/arch/powerpc/lib/string.S
> ===================================================================
> --- linux-sched-devel.git.orig/arch/powerpc/lib/string.S	2008-02-27 14:01:38.000000000 -0800
> +++ linux-sched-devel.git/arch/powerpc/lib/string.S	2008-02-29 07:24:22.000000000 -0800
> @@ -75,6 +75,18 @@ _GLOBAL(strcmp)
>  	beq	1b
>  	blr
>  
> +_GLOBAL(strncmp)
> +	mtctr	r5
> +	addi	r5,r3,-1
> +	addi	r4,r4,-1
> +1:	lbzu	r3,1(r5)
> +	cmpwi	1,r3,0
> +	lbzu	r0,1(r4)
> +	subf.	r3,r0,r3
> +	beqlr	1
> +	bdnzt	eq,1b
> +	blr
> +
>  _GLOBAL(strlen)
>  	addi	r4,r3,-1
>  1:	lbzu	r0,1(r4)
> Index: linux-sched-devel.git/include/asm-powerpc/string.h
> ===================================================================
> --- linux-sched-devel.git.orig/include/asm-powerpc/string.h	2008-02-27 14:01:58.000000000 -0800
> +++ linux-sched-devel.git/include/asm-powerpc/string.h	2008-02-29 07:24:22.000000000 -0800
> @@ -7,6 +7,7 @@
>  #define __HAVE_ARCH_STRNCPY
>  #define __HAVE_ARCH_STRLEN
>  #define __HAVE_ARCH_STRCMP
> +#define __HAVE_ARCH_STRNCMP
>  #define __HAVE_ARCH_STRCAT
>  #define __HAVE_ARCH_MEMSET
>  #define __HAVE_ARCH_MEMCPY
> @@ -18,6 +19,7 @@ extern char * strcpy(char *,const char *
>  extern char * strncpy(char *,const char *, __kernel_size_t);
>  extern __kernel_size_t strlen(const char *);
>  extern int strcmp(const char *,const char *);
> +extern int strncmp(const char *,const char *,__kernel_size_t);
>  extern char * strcat(char *, const char *);
>  extern void * memset(void *,int,__kernel_size_t);
>  extern void * memcpy(void *,const void *,__kernel_size_t);
> 
> 
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@...abs.org
> https://ozlabs.org/mailman/listinfo/linuxppc-dev

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

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