From 9939ddaff52787b2a7c1adf1b2afc95421aa0884 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 13 Jan 2009 20:41:35 +0900 Subject: x86: merge 64 and 32 SMP percpu handling Now that pda is allocated as part of percpu, percpu doesn't need to be accessed through pda. Unify x86_64 SMP percpu access with x86_32 SMP one. Other than the segment register, operand size and the base of percpu symbols, they behave identical now. This patch replaces now unnecessary pda->data_offset with a dummy field which is necessary to keep stack_canary at its place. This patch also moves per_cpu_offset initialization out of init_gdt() into setup_per_cpu_areas(). Note that this change also necessitates explicit per_cpu_offset initializations in voyager_smp.c. With this change, x86_OP_percpu()'s are as efficient on x86_64 as on x86_32 and also x86_64 can use assembly PER_CPU macros. Signed-off-by: Tejun Heo Signed-off-by: Ingo Molnar --- arch/x86/kernel/setup_percpu.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'arch/x86/kernel/setup_percpu.c') diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index 63d462802272..be1ff34db112 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -125,14 +125,14 @@ static void __init setup_per_cpu_maps(void) #endif } -#ifdef CONFIG_X86_32 -/* - * Great future not-so-futuristic plan: make i386 and x86_64 do it - * the same way - */ +#ifdef CONFIG_X86_64 +unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = { + [0] = (unsigned long)__per_cpu_load, +}; +#else unsigned long __per_cpu_offset[NR_CPUS] __read_mostly; -EXPORT_SYMBOL(__per_cpu_offset); #endif +EXPORT_SYMBOL(__per_cpu_offset); /* * Great future plan: @@ -178,6 +178,7 @@ void __init setup_per_cpu_areas(void) #endif memcpy(ptr, __per_cpu_load, __per_cpu_end - __per_cpu_start); + per_cpu_offset(cpu) = ptr - __per_cpu_start; #ifdef CONFIG_X86_64 cpu_pda(cpu) = (void *)ptr; @@ -190,7 +191,7 @@ void __init setup_per_cpu_areas(void) else memset(cpu_pda(cpu), 0, sizeof(*cpu_pda(cpu))); #endif - per_cpu_offset(cpu) = ptr - __per_cpu_start; + per_cpu(this_cpu_off, cpu) = per_cpu_offset(cpu); DBG("PERCPU: cpu %4d %p\n", cpu, ptr); } -- cgit v1.2.3