Commit 4327b15f authored by Frederic Weisbecker's avatar Frederic Weisbecker
Browse files

nohz: Consolidate nohz full init code 



The supports for CONFIG_NO_HZ_FULL_ALL=y and the nohz_full= kernel
parameter both have their own way to do the same thing: allocate
full dynticks cpumasks, fill them and initialize some state variables.

Lets consolidate that all in the same place.

While at it, convert some regular printk message to warnings when
fundamental allocations fail.

Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
parent 36310736

kernel/time/tick-sched.c

+19 −19
Original line number Original line Diff line number Diff line
@@ -295,22 +295,12 @@ out: 
/* Parse the boot-time nohz CPU list from the kernel parameters. */

/* Parse the boot-time nohz CPU list from the kernel parameters. */

static int __init tick_nohz_full_setup(char *str)

static int __init tick_nohz_full_setup(char *str)

{

{

	int cpu;



	alloc_bootmem_cpumask_var(&tick_nohz_full_mask);

	alloc_bootmem_cpumask_var(&tick_nohz_full_mask);

	alloc_bootmem_cpumask_var(&housekeeping_mask);

	if (cpulist_parse(str, tick_nohz_full_mask) < 0) {

	if (cpulist_parse(str, tick_nohz_full_mask) < 0) {

		pr_warning("NOHZ: Incorrect nohz_full cpumask\n");

		pr_warning("NOHZ: Incorrect nohz_full cpumask\n");

		free_bootmem_cpumask_var(tick_nohz_full_mask);

		return 1;

		return 1;

	}

	}



	cpu = smp_processor_id();

	if (cpumask_test_cpu(cpu, tick_nohz_full_mask)) {

		pr_warning("NO_HZ: Clearing %d from nohz_full range for timekeeping\n", cpu);

		cpumask_clear_cpu(cpu, tick_nohz_full_mask);

	}

	cpumask_andnot(housekeeping_mask,

		       cpu_possible_mask, tick_nohz_full_mask);

	tick_nohz_full_running = true;

	tick_nohz_full_running = true;





	return 1;

	return 1;
@@ -349,18 +339,11 @@ static int tick_nohz_init_all(void) 




#ifdef CONFIG_NO_HZ_FULL_ALL

#ifdef CONFIG_NO_HZ_FULL_ALL

	if (!alloc_cpumask_var(&tick_nohz_full_mask, GFP_KERNEL)) {

	if (!alloc_cpumask_var(&tick_nohz_full_mask, GFP_KERNEL)) {

		pr_err("NO_HZ: Can't allocate full dynticks cpumask\n");

		WARN(1, "NO_HZ: Can't allocate full dynticks cpumask\n");

		return err;

	}

	if (!alloc_cpumask_var(&housekeeping_mask, GFP_KERNEL)) {

		pr_err("NO_HZ: Can't allocate not-full dynticks cpumask\n");

		return err;

		return err;

	}

	}

	err = 0;

	err = 0;

	cpumask_setall(tick_nohz_full_mask);

	cpumask_setall(tick_nohz_full_mask);

	cpumask_clear_cpu(smp_processor_id(), tick_nohz_full_mask);

	cpumask_clear(housekeeping_mask);

	cpumask_set_cpu(smp_processor_id(), housekeeping_mask);

	tick_nohz_full_running = true;

	tick_nohz_full_running = true;

#endif

#endif

	return err;

	return err;
@@ -375,6 +358,23 @@ void __init tick_nohz_init(void) 
			return;

			return;

	}

	}





	if (!alloc_cpumask_var(&housekeeping_mask, GFP_KERNEL)) {

		WARN(1, "NO_HZ: Can't allocate not-full dynticks cpumask\n");

		cpumask_clear(tick_nohz_full_mask);

		tick_nohz_full_running = false;

		return;

	}



	cpu = smp_processor_id();



	if (cpumask_test_cpu(cpu, tick_nohz_full_mask)) {

		pr_warning("NO_HZ: Clearing %d from nohz_full range for timekeeping\n", cpu);

		cpumask_clear_cpu(cpu, tick_nohz_full_mask);

	}



	cpumask_andnot(housekeeping_mask,

		       cpu_possible_mask, tick_nohz_full_mask);



	for_each_cpu(cpu, tick_nohz_full_mask)

	for_each_cpu(cpu, tick_nohz_full_mask)

		context_tracking_cpu_set(cpu);

		context_tracking_cpu_set(cpu);

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