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| author | Mike Travis | 2007-10-19 20:35:03 +0200 |
|---|---|---|
| committer | Thomas Gleixner | 2007-10-19 20:35:03 +0200 |
| commit | 71fff5e6ca1b738ac4742580e4c0ff79d906f6c8 (patch) | |
| tree | 390e67123d684ab7f490291db987e097e5b3c728 /arch/x86/kernel/mpparse_64.c | |
| parent | i386: introduce "used_vectors" bitmap which can be used to reserve vectors. (diff) | |
| download | kernel-qcow2-linux-71fff5e6ca1b738ac4742580e4c0ff79d906f6c8.tar.gz kernel-qcow2-linux-71fff5e6ca1b738ac4742580e4c0ff79d906f6c8.tar.xz kernel-qcow2-linux-71fff5e6ca1b738ac4742580e4c0ff79d906f6c8.zip | |
x86: convert cpu_to_apicid to be a per cpu variable
This patch converts the x86_cpu_to_apicid array to be a per cpu
variable. This saves sizeof(apicid) * NR unused cpus. Access is mostly
from startup and CPU HOTPLUG functions.
MP_processor_info() is one of the functions that require access to the
x86_cpu_to_apicid array before the per_cpu data area is setup. For this
case, a pointer to the __initdata array is initialized in setup_arch()
and removed in smp_prepare_cpus() after the per_cpu data area is
initialized.
A second change is included to change the initial array value of ARCH
i386 from 0xff to BAD_APICID to be consistent with ARCH x86_64.
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/kernel/mpparse_64.c')
| -rw-r--r-- | arch/x86/kernel/mpparse_64.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/x86/kernel/mpparse_64.c b/arch/x86/kernel/mpparse_64.c index 8bf0ca03ac8e..4336c0fc3b81 100644 --- a/arch/x86/kernel/mpparse_64.c +++ b/arch/x86/kernel/mpparse_64.c @@ -86,7 +86,7 @@ static int __init mpf_checksum(unsigned char *mp, int len) return sum & 0xFF; } -static void __cpuinit MP_processor_info (struct mpc_config_processor *m) +static void __cpuinit MP_processor_info(struct mpc_config_processor *m) { int cpu; cpumask_t tmp_map; @@ -123,7 +123,18 @@ static void __cpuinit MP_processor_info (struct mpc_config_processor *m) cpu = 0; } bios_cpu_apicid[cpu] = m->mpc_apicid; - x86_cpu_to_apicid[cpu] = m->mpc_apicid; + /* + * We get called early in the the start_kernel initialization + * process when the per_cpu data area is not yet setup, so we + * use a static array that is removed after the per_cpu data + * area is created. + */ + if (x86_cpu_to_apicid_ptr) { + u8 *x86_cpu_to_apicid = (u8 *)x86_cpu_to_apicid_ptr; + x86_cpu_to_apicid[cpu] = m->mpc_apicid; + } else { + per_cpu(x86_cpu_to_apicid, cpu) = m->mpc_apicid; + } cpu_set(cpu, cpu_possible_map); cpu_set(cpu, cpu_present_map); |