Revert "x86/smpboot: Initialize secondary CPU only if master CPU will wait for it" (bb077d60) · Commits · 戴 / test

arch/x86/kernel/cpu/common.c

+11 −16

Original line number	Diff line number	Diff line
		@@ -1221,17 +1221,6 @@ static void dbg_restore_debug_regs(void)
		#define dbg_restore_debug_regs()
		#endif /* ! CONFIG_KGDB */

		static void wait_for_master_cpu(int cpu)
		{
		/*
		* wait for ACK from master CPU before continuing
		* with AP initialization
		*/
		WARN_ON(cpumask_test_and_set_cpu(cpu, cpu_initialized_mask));
		while (!cpumask_test_cpu(cpu, cpu_callout_mask))
		cpu_relax();
		}

		/*
		* cpu_init() initializes state that is per-CPU. Some data is already
		* initialized (naturally) in the bootstrap process, such as the GDT
		@@ -1247,17 +1236,16 @@ void cpu_init(void)
		struct task_struct *me;
		struct tss_struct *t;
		unsigned long v;
		int cpu = stack_smp_processor_id();
		int cpu;
		int i;

		wait_for_master_cpu(cpu);

		/*
		* Load microcode on this cpu if a valid microcode is available.
		* This is early microcode loading procedure.
		*/
		load_ucode_ap();

		cpu = stack_smp_processor_id();
		t = &per_cpu(init_tss, cpu);
		oist = &per_cpu(orig_ist, cpu);

		@@ -1269,6 +1257,9 @@ void cpu_init(void)

		me = current;

		if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask))
		panic("CPU#%d already initialized!\n", cpu);

		pr_debug("Initializing CPU#%d\n", cpu);

		clear_in_cr4(X86_CR4_VME\|X86_CR4_PVI\|X86_CR4_TSD\|X86_CR4_DE);
		@@ -1345,10 +1336,14 @@ void cpu_init(void)
		struct tss_struct *t = &per_cpu(init_tss, cpu);
		struct thread_struct *thread = &curr->thread;

		wait_for_master_cpu(cpu);

		show_ucode_info_early();

		if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask)) {
		printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
		for (;;)
		local_irq_enable();
		}

		printk(KERN_INFO "Initializing CPU#%d\n", cpu);

		if (cpu_has_vme \|\| cpu_has_tsc \|\| cpu_has_de)

arch/x86/kernel/smpboot.c

+68 −31

Original line number	Diff line number	Diff line
		@@ -111,6 +111,7 @@ atomic_t init_deasserted;
		static void smp_callin(void)
		{
		int cpuid, phys_id;
		unsigned long timeout;

		/*
		* If waken up by an INIT in an 82489DX configuration
		@@ -129,6 +130,37 @@ static void smp_callin(void)
		* (This works even if the APIC is not enabled.)
		*/
		phys_id = read_apic_id();
		if (cpumask_test_cpu(cpuid, cpu_callin_mask)) {
		panic("%s: phys CPU#%d, CPU#%d already present??\n", __func__,
		phys_id, cpuid);
		}
		pr_debug("CPU#%d (phys ID: %d) waiting for CALLOUT\n", cpuid, phys_id);

		/*
		* STARTUP IPIs are fragile beasts as they might sometimes
		* trigger some glue motherboard logic. Complete APIC bus
		* silence for 1 second, this overestimates the time the
		* boot CPU is spending to send the up to 2 STARTUP IPIs
		* by a factor of two. This should be enough.
		*/

		/*
		* Waiting 2s total for startup (udelay is not yet working)
		*/
		timeout = jiffies + 2*HZ;
		while (time_before(jiffies, timeout)) {
		/*
		* Has the boot CPU finished it's STARTUP sequence?
		*/
		if (cpumask_test_cpu(cpuid, cpu_callout_mask))
		break;
		cpu_relax();
		}

		if (!time_before(jiffies, timeout)) {
		panic("%s: CPU%d started up but did not get a callout!\n",
		__func__, cpuid);
		}

		/*
		* the boot CPU has finished the init stage and is spinning
		@@ -718,8 +750,8 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
		unsigned long start_ip = real_mode_header->trampoline_start;

		unsigned long boot_error = 0;
		int timeout;
		int cpu0_nmi_registered = 0;
		unsigned long timeout;

		/* Just in case we booted with a single CPU. */
		alternatives_enable_smp();
		@@ -766,15 +798,6 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
		}
		}

		/*
		* AP might wait on cpu_callout_mask in cpu_init() with
		* cpu_initialized_mask set if previous attempt to online
		* it timed-out. Clear cpu_initialized_mask so that after
		* INIT/SIPI it could start with a clean state.
		*/
		cpumask_clear_cpu(cpu, cpu_initialized_mask);
		smp_mb();

		/*
		* Wake up a CPU in difference cases:
		* - Use the method in the APIC driver if it's defined
		@@ -787,41 +810,55 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
		boot_error = wakeup_cpu_via_init_nmi(cpu, start_ip, apicid,
		&cpu0_nmi_registered);


		if (!boot_error) {
		/*
		* Wait 10s total for a response from AP
		*/
		boot_error = -1;
		timeout = jiffies + 10*HZ;
		while (time_before(jiffies, timeout)) {
		if (cpumask_test_cpu(cpu, cpu_initialized_mask)) {
		/*
		* Tell AP to proceed with initialization
		* allow APs to start initializing.
		*/
		pr_debug("Before Callout %d\n", cpu);
		cpumask_set_cpu(cpu, cpu_callout_mask);
		boot_error = 0;
		break;
		}
		udelay(100);
		schedule();
		}
		}
		pr_debug("After Callout %d\n", cpu);

		if (!boot_error) {
		/*
		* Wait till AP completes initial initialization
		* Wait 5s total for a response
		*/
		while (!cpumask_test_cpu(cpu, cpu_callin_mask)) {
		for (timeout = 0; timeout < 50000; timeout++) {
		if (cpumask_test_cpu(cpu, cpu_callin_mask))
		break; /* It has booted */
		udelay(100);
		/*
		* Allow other tasks to run while we wait for the
		* AP to come online. This also gives a chance
		* for the MTRR work(triggered by the AP coming online)
		* to be completed in the stop machine context.
		*/
		udelay(100);
		schedule();
		}

		if (cpumask_test_cpu(cpu, cpu_callin_mask)) {
		print_cpu_msr(&cpu_data(cpu));
		pr_debug("CPU%d: has booted.\n", cpu);
		} else {
		boot_error = 1;
		if (*trampoline_status == 0xA5A5A5A5)
		/* trampoline started but...? */
		pr_err("CPU%d: Stuck ??\n", cpu);
		else
		/* trampoline code not run */
		pr_err("CPU%d: Not responding\n", cpu);
		if (apic->inquire_remote_apic)
		apic->inquire_remote_apic(apicid);
		}
		}

		if (boot_error) {
		/* Try to put things back the way they were before ... */
		numa_remove_cpu(cpu); /* was set by numa_add_cpu */

		/* was set by do_boot_cpu() */
		cpumask_clear_cpu(cpu, cpu_callout_mask);

		/* was set by cpu_init() */
		cpumask_clear_cpu(cpu, cpu_initialized_mask);
		}

		/* mark "stuck" area as not stuck */

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