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Commit d05d15da authored by Heiko Carstens's avatar Heiko Carstens Committed by Martin Schwidefsky
Browse files

s390/topology: delay initialization of topology cpu masks 



There is no reason to initialize the topology cpu masks already while
setup_arch() is being called. It is sufficient to initialize the masks
before the scheduler becomes SMP aware.
Therefore a pre-SMP initcall aka early_initcall is suffucient.

This also allows to convert the cpu_topology array into a per cpu
variable with a later patch. Without this patch this wouldn't be
possible since the per cpu memory areas are not allocated while setup_arch
is executed.

Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 49253925

arch/s390/include/asm/topology.h

+0 −8
Original line number Diff line number Diff line
@@ -51,14 +51,6 @@ static inline void topology_expect_change(void) { } 
#define POLARIZATION_VM		(2)

#define POLARIZATION_VH		(3)



#ifdef CONFIG_SCHED_BOOK

void s390_init_cpu_topology(void);

#else

static inline void s390_init_cpu_topology(void)

{

};

#endif



#include <asm-generic/topology.h>



#endif /* _ASM_S390_TOPOLOGY_H */

arch/s390/kernel/setup.c

+0 −1
Original line number Diff line number Diff line
@@ -909,7 +909,6 @@ void __init setup_arch(char **cmdline_p) 
	setup_lowcore();

	smp_fill_possible_mask();

        cpu_init();

	s390_init_cpu_topology();



	/*

	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).

arch/s390/kernel/topology.c

+47 −53
Original line number Diff line number Diff line
@@ -7,14 +7,14 @@ 
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt



#include <linux/workqueue.h>

#include <linux/bootmem.h>

#include <linux/cpuset.h>

#include <linux/device.h>

#include <linux/export.h>

#include <linux/kernel.h>

#include <linux/sched.h>

#include <linux/init.h>

#include <linux/delay.h>

#include <linux/init.h>

#include <linux/slab.h>

#include <linux/cpu.h>

#include <linux/smp.h>

#include <linux/mm.h>
@@ -334,50 +334,6 @@ void topology_expect_change(void) 
	set_topology_timer();

}



static int __init early_parse_topology(char *p)

{

	if (strncmp(p, "off", 3))

		return 0;

	topology_enabled = 0;

	return 0;

}

early_param("topology", early_parse_topology);



static void __init alloc_masks(struct sysinfo_15_1_x *info,

			       struct mask_info *mask, int offset)

{

	int i, nr_masks;



	nr_masks = info->mag[TOPOLOGY_NR_MAG - offset];

	for (i = 0; i < info->mnest - offset; i++)

		nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i];

	nr_masks = max(nr_masks, 1);

	for (i = 0; i < nr_masks; i++) {

		mask->next = alloc_bootmem_align(

			roundup_pow_of_two(sizeof(struct mask_info)),

			roundup_pow_of_two(sizeof(struct mask_info)));

		mask = mask->next;

	}

}



void __init s390_init_cpu_topology(void)

{

	struct sysinfo_15_1_x *info;

	int i;



	if (!MACHINE_HAS_TOPOLOGY)

		return;

	tl_info = alloc_bootmem_pages(PAGE_SIZE);

	info = tl_info;

	store_topology(info);

	pr_info("The CPU configuration topology of the machine is:");

	for (i = 0; i < TOPOLOGY_NR_MAG; i++)

		printk(KERN_CONT " %d", info->mag[i]);

	printk(KERN_CONT " / %d\n", info->mnest);

	alloc_masks(info, &socket_info, 1);

	alloc_masks(info, &book_info, 2);

}



static int cpu_management;



static ssize_t dispatching_show(struct device *dev,
@@ -481,6 +437,15 @@ static const struct cpumask *cpu_book_mask(int cpu) 
	return &cpu_topology[cpu].book_mask;

}



static int __init early_parse_topology(char *p)

{

	if (strncmp(p, "off", 3))

		return 0;

	topology_enabled = 0;

	return 0;

}

early_param("topology", early_parse_topology);



static struct sched_domain_topology_level s390_topology[] = {

	{ cpu_thread_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },

	{ cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
@@ -489,6 +454,42 @@ static struct sched_domain_topology_level s390_topology[] = { 
	{ NULL, },

};



static void __init alloc_masks(struct sysinfo_15_1_x *info,

			       struct mask_info *mask, int offset)

{

	int i, nr_masks;



	nr_masks = info->mag[TOPOLOGY_NR_MAG - offset];

	for (i = 0; i < info->mnest - offset; i++)

		nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i];

	nr_masks = max(nr_masks, 1);

	for (i = 0; i < nr_masks; i++) {

		mask->next = kzalloc(sizeof(*mask->next), GFP_KERNEL);

		mask = mask->next;

	}

}



static int __init s390_topology_init(void)

{

	struct sysinfo_15_1_x *info;

	int i;



	if (!MACHINE_HAS_TOPOLOGY)

		return 0;

	tl_info = (struct sysinfo_15_1_x *)__get_free_page(GFP_KERNEL);

	info = tl_info;

	store_topology(info);

	pr_info("The CPU configuration topology of the machine is:");

	for (i = 0; i < TOPOLOGY_NR_MAG; i++)

		printk(KERN_CONT " %d", info->mag[i]);

	printk(KERN_CONT " / %d\n", info->mnest);

	alloc_masks(info, &socket_info, 1);

	alloc_masks(info, &book_info, 2);

	set_sched_topology(s390_topology);

	return 0;

}

early_initcall(s390_topology_init);



static int __init topology_init(void)

{

	if (MACHINE_HAS_TOPOLOGY)
@@ -498,10 +499,3 @@ static int __init topology_init(void) 
	return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching);

}

device_initcall(topology_init);
 


static int __init early_topology_init(void)

{

	set_sched_topology(s390_topology);

	return 0;

}

early_initcall(early_topology_init);