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| author | Thomas Gleixner <tglx@linutronix.de> | 2014-12-05 08:48:29 +0000 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2014-12-06 00:19:25 +0100 |
| commit | dd60143c04f257bace7c8d805eb1f4aec461b138 (patch) | |
| tree | 4f663cee7e93d33cbbde780dfbc3ef1ba3a98e82 | |
| parent | e7faf4ec46409eb07914beabd224eefbdc48a61a (diff) | |
| download | apic-dd60143c04f257bace7c8d805eb1f4aec461b138.tar.gz | |
x86, smpboot: Remove pointless preempt_disable() in native_smp_prepare_cpus()
There is no reason to keep preemption disabled in this function.
We only have two other threads live: kthreadd and idle. Neither of
them is going to preempt. But that preempt_disable forces all the code
inside to do GFP_ATOMIC allocations which is just insane.
Remove it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20141205084147.153643952@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | arch/x86/kernel/smpboot.c | 8 |
1 files changed, 1 insertions, 7 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 4d2128ac70bdab..2dc789da90eb3c 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1084,7 +1084,6 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) { unsigned int i; - preempt_disable(); smp_cpu_index_default(); /* @@ -1102,22 +1101,19 @@ 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"); disable_smp(); - goto out; + return; } default_setup_apic_routing(); - preempt_disable(); if (read_apic_id() != boot_cpu_physical_apicid) { panic("Boot APIC ID in local APIC unexpected (%d vs %d)", read_apic_id(), boot_cpu_physical_apicid); /* Or can we switch back to PIC here? */ } - preempt_enable(); connect_bsp_APIC(); @@ -1151,8 +1147,6 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) uv_system_init(); set_mtrr_aps_delayed_init(); -out: - preempt_enable(); } void arch_enable_nonboot_cpus_begin(void) |