Commit-ID: 613c25efbdc763ee8b9d732368106d2456279356 Gitweb: http://git.kernel.org/tip/613c25efbdc763ee8b9d732368106d2456279356 Author: Thomas Gleixner <t...@linutronix.de> AuthorDate: Thu, 15 Jan 2015 21:22:42 +0000 Committer: Thomas Gleixner <t...@linutronix.de> CommitDate: Thu, 22 Jan 2015 15:10:56 +0100
x86/smpboot: Sanitize uniprocessor init The UP related setups for local apic are mangled into smp_sanity_check(). That results in duplicate calls to disable_smp() and makes the code hard to follow. Let smp_sanity_check() return dedicated values for the various exit reasons and handle them at the call site. Signed-off-by: Thomas Gleixner <t...@linutronix.de> Acked-by: Borislav Petkov <b...@alien8.de> Cc: Jiang Liu <jiang....@linux.intel.com> Cc: Joerg Roedel <j...@8bytes.org> Cc: Tony Luck <tony.l...@intel.com> Link: http://lkml.kernel.org/r/20150115211703.987833...@linutronix.de Signed-off-by: Thomas Gleixner <t...@linutronix.de> --- arch/x86/kernel/smpboot.c | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index d538709..fe8783d 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -990,6 +990,8 @@ void arch_disable_smp_support(void) */ static __init void disable_smp(void) { + pr_info("SMP disabled\n"); + disable_ioapic_support(); init_cpu_present(cpumask_of(0)); @@ -1003,6 +1005,13 @@ static __init void disable_smp(void) cpumask_set_cpu(0, cpu_core_mask(0)); } +enum { + SMP_OK, + SMP_NO_CONFIG, + SMP_NO_APIC, + SMP_FORCE_UP, +}; + /* * Various sanity checks. */ @@ -1050,10 +1059,7 @@ static int __init smp_sanity_check(unsigned max_cpus) if (!smp_found_config && !acpi_lapic) { preempt_enable(); pr_notice("SMP motherboard not detected\n"); - disable_smp(); - if (APIC_init_uniprocessor()) - pr_notice("Local APIC not detected. Using dummy APIC emulation.\n"); - return -1; + return SMP_NO_CONFIG; } /* @@ -1077,7 +1083,7 @@ static int __init smp_sanity_check(unsigned max_cpus) boot_cpu_physical_apicid); pr_err("... forcing use of dummy APIC emulation (tell your hw vendor)\n"); } - return -1; + return SMP_NO_APIC; } verify_local_APIC(); @@ -1087,12 +1093,10 @@ static int __init smp_sanity_check(unsigned max_cpus) */ if (!max_cpus) { pr_info("SMP mode deactivated\n"); - disable_ioapic_support(); - apic_bsp_setup(); - return -1; + return SMP_FORCE_UP; } - return 0; + return SMP_OK; } static void __init smp_cpu_index_default(void) @@ -1132,10 +1136,21 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) } set_cpu_sibling_map(0); - if (smp_sanity_check(max_cpus) < 0) { - pr_info("SMP disabled\n"); + switch (smp_sanity_check(max_cpus)) { + case SMP_NO_CONFIG: disable_smp(); + if (APIC_init_uniprocessor()) + pr_notice("Local APIC not detected. Using dummy APIC emulation.\n"); + return; + case SMP_NO_APIC: + disable_smp(); + return; + case SMP_FORCE_UP: + disable_smp(); + apic_bsp_setup(); return; + case SMP_OK: + break; } default_setup_apic_routing(); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
