linux-kernel - Re: [PATCH 07/15] x86: add xadd helper macro

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, 23 Aug 2011 12:59:32 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Jeremy Fitzhardinge <jeremy@...p.org>
Cc:	"H. Peter Anvin" <hpa@...or.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Ingo Molnar <mingo@...e.hu>,
	the arch/x86 maintainers <x86@...nel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Nick Piggin <npiggin@...nel.dk>,
	Jeremy Fitzhardinge <jeremy.fitzhardinge@...rix.com>
Subject: Re: [PATCH 07/15] x86: add xadd helper macro



What you could do is something like:

#define CASE_B	case 1
#define CASE_W	case 2
#define CASE_L	case 4
#ifdef CONFIG_64BIT
# define CASE_Q	case 8
#else
# define CASE_Q case -1 /* sizeof() won't ever return this */
#endif


> +#define xadd(ptr, inc)                                                 \
> +       do {                                                            \
> +               switch (sizeof(*(ptr))) {                               \
                 CASE_B:                                                 \
> +                       asm volatile (LOCK_PREFIX "xaddb %b0, %1\n"     \
> +                                     : "+r" (inc), "+m" (*(ptr))       \
> +                                     : : "memory", "cc");              \
> +                       break;                                          \
		 CASE_W:                                                 \
> +                       asm volatile (LOCK_PREFIX "xaddw %w0, %1\n"     \
> +                                     : "+r" (inc), "+m" (*(ptr))       \
> +                                     : : "memory", "cc");              \
> +                       break;                                          \
                 CASE_L:                                                 \
> +                       asm volatile (LOCK_PREFIX "xaddl %0, %1\n"      \
> +                                     : "+r" (inc), "+m" (*(ptr))       \
> +                                     : : "memory", "cc");              \
> +                       break;                                          \
                 CASE_Q:                                                 \
> +                       asm volatile (LOCK_PREFIX "xaddq %q0, %1\n"     \
> +                                     : "+r" (inc), "+m" (*(ptr))       \
> +                                     : : "memory", "cc");              \
> +                       break;                                          \
		 default:						 \
			 __xadd_wrong_size();				 \
> +               }                                                       \
> +       } while(0) 


--
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/