* Relocate the x86_64 percpu variables to begin at zero. Then we can directly use the x86_32 percpu operations. x86_32 offsets %fs by __per_cpu_start. x86_64 has %gs pointing directly to the pda and the per cpu area thereby allowing access to the pda with the x86_64 pda operations and access to the per cpu variables using x86_32 percpu operations. * This also supports further integration of x86_32/64. Based on 2.6.24-rc8-mm1 Signed-off-by: Mike Travis Reviewed-by: Christoph Lameter --- arch/x86/Kconfig | 3 +++ arch/x86/kernel/setup64.c | 2 +- arch/x86/kernel/vmlinux_64.lds.S | 1 + kernel/module.c | 7 ++++--- 4 files changed, 9 insertions(+), 4 deletions(-) --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -107,6 +107,9 @@ config GENERIC_TIME_VSYSCALL bool default X86_64 +config HAVE_ZERO_BASED_PER_CPU + def_bool X86_64 + config ARCH_SUPPORTS_OPROFILE bool default y --- a/arch/x86/kernel/setup64.c +++ b/arch/x86/kernel/setup64.c @@ -152,7 +152,7 @@ void __init setup_per_cpu_areas(void) } if (!ptr) panic("Cannot allocate cpu data for CPU %d\n", i); - memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start); + memcpy(ptr, __per_cpu_load, __per_cpu_size); /* Relocate the pda */ memcpy(ptr, cpu_pda(i), sizeof(struct x8664_pda)); cpu_pda(i) = (struct x8664_pda *)ptr; --- a/arch/x86/kernel/vmlinux_64.lds.S +++ b/arch/x86/kernel/vmlinux_64.lds.S @@ -16,6 +16,7 @@ jiffies_64 = jiffies; _proxy_pda = 1; PHDRS { text PT_LOAD FLAGS(5); /* R_E */ + percpu PT_LOAD FLAGS(4); /* R__ */ data PT_LOAD FLAGS(7); /* RWE */ user PT_LOAD FLAGS(7); /* RWE */ data.init PT_LOAD FLAGS(7); /* RWE */ --- a/kernel/module.c +++ b/kernel/module.c @@ -45,6 +45,7 @@ #include #include #include +#include #include #include @@ -351,7 +352,7 @@ static void *percpu_modalloc(unsigned lo align = PAGE_SIZE; } - ptr = __per_cpu_start; + ptr = __per_cpu_load; for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) { /* Extra for alignment requirement. */ extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr; @@ -386,7 +387,7 @@ static void *percpu_modalloc(unsigned lo static void percpu_modfree(void *freeme) { unsigned int i; - void *ptr = __per_cpu_start + block_size(pcpu_size[0]); + void *ptr = __per_cpu_load + block_size(pcpu_size[0]); /* First entry is core kernel percpu data. */ for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) { @@ -437,7 +438,7 @@ static int percpu_modinit(void) pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated, GFP_KERNEL); /* Static in-kernel percpu data (used). */ - pcpu_size[0] = -(__per_cpu_end-__per_cpu_start); + pcpu_size[0] = -__per_cpu_size; /* Free room. */ pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0]; if (pcpu_size[1] < 0) { -- -- 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/