Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 17 Dec 2002 14:52:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 17 Dec 2002 14:52:48 -0500 Received: from neon-gw-l3.transmeta.com ([63.209.4.196]:2569 "EHLO neon-gw.transmeta.com") by vger.kernel.org with ESMTP id ; Tue, 17 Dec 2002 14:52:07 -0500 Date: Tue, 17 Dec 2002 12:01:06 -0800 (PST) From: Linus Torvalds To: Ulrich Drepper cc: Matti Aarnio , Hugh Dickins , Dave Jones , Ingo Molnar , , Subject: Re: Intel P6 vs P7 system call performance In-Reply-To: <3DFF80BC.2020709@redhat.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2896 Lines: 109 How about this diff? It does both the 6-parameter thing _and_ the AT_SYSINFO addition. Untested, since I have to run off and watch my kids do their winter program ;) Linus ----- ===== arch/i386/kernel/entry.S 1.42 vs edited ===== --- 1.42/arch/i386/kernel/entry.S Mon Dec 16 21:39:04 2002 +++ edited/arch/i386/kernel/entry.S Tue Dec 17 11:59:13 2002 @@ -232,7 +232,7 @@ #endif /* Points to after the "sysenter" instruction in the vsyscall page */ -#define SYSENTER_RETURN 0xfffff007 +#define SYSENTER_RETURN 0xffffe007 # sysenter call handler stub ALIGN @@ -243,6 +243,21 @@ pushfl pushl $(__USER_CS) pushl $SYSENTER_RETURN + +/* + * Load the potential sixth argument from user stack. + * Careful about security. + */ + cmpl $0xc0000000,%ebp + jae syscall_badsys +1: movl (%ebp),%ebp +.section .fixup,"ax" +2: xorl %ebp,%ebp +.previous +.section __ex_table,"a" + .align 4 + .long 1b,2b +.previous pushl %eax SAVE_ALL ===== arch/i386/kernel/sysenter.c 1.1 vs edited ===== --- 1.1/arch/i386/kernel/sysenter.c Mon Dec 16 21:39:04 2002 +++ edited/arch/i386/kernel/sysenter.c Tue Dec 17 11:39:39 2002 @@ -48,14 +48,14 @@ 0xc3 /* ret */ }; static const char sysent[] = { - 0x55, /* push %ebp */ 0x51, /* push %ecx */ 0x52, /* push %edx */ + 0x55, /* push %ebp */ 0x89, 0xe5, /* movl %esp,%ebp */ 0x0f, 0x34, /* sysenter */ + 0x5d, /* pop %ebp */ 0x5a, /* pop %edx */ 0x59, /* pop %ecx */ - 0x5d, /* pop %ebp */ 0xc3 /* ret */ }; unsigned long page = get_zeroed_page(GFP_ATOMIC); ===== include/asm-i386/elf.h 1.3 vs edited ===== --- 1.3/include/asm-i386/elf.h Thu Oct 17 00:48:55 2002 +++ edited/include/asm-i386/elf.h Tue Dec 17 10:12:58 2002 @@ -100,6 +100,12 @@ #define ELF_PLATFORM (system_utsname.machine) +/* + * Architecture-neutral AT_ values in 0-17, leave some room + * for more of them, start the x86-specific ones at 32. + */ +#define AT_SYSINFO 32 + #ifdef __KERNEL__ #define SET_PERSONALITY(ex, ibcs2) set_personality((ibcs2)?PER_SVR4:PER_LINUX) @@ -115,6 +121,11 @@ extern void dump_smp_unlazy_fpu(void); #define ELF_CORE_SYNC dump_smp_unlazy_fpu #endif + +#define ARCH_DLINFO \ +do { \ + NEW_AUX_ENT(AT_SYSINFO, 0xffffe000); \ +} while (0) #endif ===== include/asm-i386/fixmap.h 1.9 vs edited ===== --- 1.9/include/asm-i386/fixmap.h Mon Dec 16 21:39:04 2002 +++ edited/include/asm-i386/fixmap.h Tue Dec 17 10:11:31 2002 @@ -42,8 +42,8 @@ * task switches. */ enum fixed_addresses { - FIX_VSYSCALL, FIX_HOLE, + FIX_VSYSCALL, #ifdef CONFIG_X86_LOCAL_APIC FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */ #endif - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/