Commit 52aeda7a authored by Alexander Gordeev's avatar Alexander Gordeev Committed by Vasily Gorbik
Browse files

s390/topology: remove offline CPUs from CPU topology masks 



The CPU topology masks on s390 contain also bits of CPUs which
are offline. Currently this is already a problem, since common
code scheduler expects e.g. cpu_smt_mask() to reflect reality.

This update changes the described behaviour and s390 starts to
behave like all other architectures.

Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent cd8e702f

arch/s390/include/asm/topology.h

+2 −0
Original line number Diff line number Diff line
@@ -43,6 +43,7 @@ int topology_cpu_init(struct cpu *); 
int topology_set_cpu_management(int fc);

void topology_schedule_update(void);

void store_topology(struct sysinfo_15_1_x *info);

void update_cpu_masks(void);

void topology_expect_change(void);

const struct cpumask *cpu_coregroup_mask(int cpu);
@@ -52,6 +53,7 @@ static inline void topology_init_early(void) { } 
static inline void topology_schedule_update(void) { }

static inline int topology_cpu_init(struct cpu *cpu) { return 0; }

static inline int topology_cpu_dedicated(int cpu_nr) { return 0; }

static inline void update_cpu_masks(void) { }

static inline void topology_expect_change(void) { }



#endif /* CONFIG_SCHED_TOPOLOGY */

arch/s390/kernel/smp.c

+4 −2
Original line number Diff line number Diff line
@@ -858,12 +858,13 @@ static void smp_init_secondary(void) 
	init_cpu_timer();

	vtime_init();

	pfault_init();

	notify_cpu_starting(smp_processor_id());

	notify_cpu_starting(cpu);

	if (topology_cpu_dedicated(cpu))

		set_cpu_flag(CIF_DEDICATED_CPU);

	else

		clear_cpu_flag(CIF_DEDICATED_CPU);

	set_cpu_online(smp_processor_id(), true);

	set_cpu_online(cpu, true);

	update_cpu_masks();

	inc_irq_stat(CPU_RST);

	local_irq_enable();

	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
@@ -935,6 +936,7 @@ int __cpu_disable(void) 
	/* Handle possible pending IPIs */

	smp_handle_ext_call();

	set_cpu_online(smp_processor_id(), false);

	update_cpu_masks();

	/* Disable pseudo page faults on this cpu. */

	pfault_fini();

	/* Disable interrupt sources via control register. */

arch/s390/kernel/topology.c

+3 −1
Original line number Diff line number Diff line
@@ -88,6 +88,7 @@ static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu) 
		cpumask_copy(&mask, cpumask_of(cpu));

		break;

	}

	cpumask_and(&mask, &mask, cpu_online_mask);

	return mask;

}
@@ -103,6 +104,7 @@ static cpumask_t cpu_thread_map(unsigned int cpu) 
	for (i = 0; i <= smp_cpu_mtid; i++)

		if (cpu_present(cpu + i))

			cpumask_set_cpu(cpu + i, &mask);

	cpumask_and(&mask, &mask, cpu_online_mask);

	return mask;

}
@@ -241,7 +243,7 @@ int topology_set_cpu_management(int fc) 
	return rc;

}



static void update_cpu_masks(void)

void update_cpu_masks(void)

{

	struct cpu_topology_s390 *topo;

	int cpu, id;

CRA Git | Maintained and supported by SUSTech CRA and CCSE