Commit f6bf1a8a authored by Heiko Carstens's avatar Heiko Carstens Committed by Martin Schwidefsky
Browse files

[S390] topology: fix topology on z10 machines 



Make sure that all cpus in a book on a z10 appear as book siblings
and not as core siblings. This fixes some performance regressions that
appeared after the book scheduling domain got introduced.

Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 6ed54387

arch/s390/kernel/topology.c

+38 −7
Original line number Diff line number Diff line
@@ -68,8 +68,10 @@ static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu) 
	return mask;

}



static void add_cpus_to_mask(struct topology_cpu *tl_cpu,

			     struct mask_info *book, struct mask_info *core)

static struct mask_info *add_cpus_to_mask(struct topology_cpu *tl_cpu,

					  struct mask_info *book,

					  struct mask_info *core,

					  int z10)

{

	unsigned int cpu;
@@ -88,10 +90,16 @@ static void add_cpus_to_mask(struct topology_cpu *tl_cpu, 
			cpu_book_id[lcpu] = book->id;

#endif

			cpumask_set_cpu(lcpu, &core->mask);

			if (z10) {

				cpu_core_id[lcpu] = rcpu;

				core = core->next;

			} else {

				cpu_core_id[lcpu] = core->id;

			}

			smp_cpu_polarization[lcpu] = tl_cpu->pp;

		}

	}

	return core;

}



static void clear_masks(void)
@@ -123,18 +131,41 @@ static void tl_to_cores(struct sysinfo_15_1_x *info) 
{

#ifdef CONFIG_SCHED_BOOK

	struct mask_info *book = &book_info;

	struct cpuid cpu_id;

#else

	struct mask_info *book = NULL;

#endif

	struct mask_info *core = &core_info;

	union topology_entry *tle, *end;

	int z10 = 0;





#ifdef CONFIG_SCHED_BOOK

	get_cpu_id(&cpu_id);

	z10 = cpu_id.machine == 0x2097 || cpu_id.machine == 0x2098;

#endif

	spin_lock_irq(&topology_lock);

	clear_masks();

	tle = info->tle;

	end = (union topology_entry *)((unsigned long)info + info->length);

	while (tle < end) {

#ifdef CONFIG_SCHED_BOOK

		if (z10) {

			switch (tle->nl) {

			case 1:

				book = book->next;

				book->id = tle->container.id;

				break;

			case 0:

				core = add_cpus_to_mask(&tle->cpu, book, core, z10);

				break;

			default:

				clear_masks();

				goto out;

			}

			tle = next_tle(tle);

			continue;

		}

#endif

		switch (tle->nl) {

#ifdef CONFIG_SCHED_BOOK

		case 2:
@@ -147,7 +178,7 @@ static void tl_to_cores(struct sysinfo_15_1_x *info) 
			core->id = tle->container.id;

			break;

		case 0:

			add_cpus_to_mask(&tle->cpu, book, core);

			add_cpus_to_mask(&tle->cpu, book, core, z10);

			break;

		default:

			clear_masks();
@@ -328,8 +359,8 @@ void __init s390_init_cpu_topology(void) 
	for (i = 0; i < TOPOLOGY_NR_MAG; i++)

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

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

	alloc_masks(info, &core_info, 2);

	alloc_masks(info, &core_info, 1);

#ifdef CONFIG_SCHED_BOOK

	alloc_masks(info, &book_info, 3);

	alloc_masks(info, &book_info, 2);

#endif

}