linux/arch/s390/include/asm/smp.h
Sven Schnelle a052096bdd s390/topology: fix topology information when calling cpu hotplug notifiers
The cpu hotplug notifiers are called without updating the core/thread
masks when a new CPU is added. This causes problems with code setting
up data structures in a cpu hotplug notifier, and relying on that later
in normal code.

This caused a crash in the new core scheduling code (SCHED_CORE),
where rq->core was set up in a notifier depending on cpu masks.

To fix this, add a cpu_setup_mask which is used in update_cpu_masks()
instead of the cpu_online_mask to determine whether the cpu masks should
be set for a certain cpu. Also move update_cpu_masks() to update the
masks before calling notify_cpu_starting() so that the notifiers are
seeing the updated masks.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Cc: <stable@vger.kernel.org>
[hca@linux.ibm.com: get rid of cpu_online_mask handling]
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-09-07 13:38:41 +02:00

70 lines
1.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright IBM Corp. 1999, 2012
* Author(s): Denis Joseph Barrow,
* Martin Schwidefsky <schwidefsky@de.ibm.com>,
* Heiko Carstens <heiko.carstens@de.ibm.com>,
*/
#ifndef __ASM_SMP_H
#define __ASM_SMP_H
#include <asm/sigp.h>
#include <asm/lowcore.h>
#include <asm/processor.h>
#define raw_smp_processor_id() (S390_lowcore.cpu_nr)
extern struct mutex smp_cpu_state_mutex;
extern unsigned int smp_cpu_mt_shift;
extern unsigned int smp_cpu_mtid;
extern __vector128 __initdata boot_cpu_vector_save_area[__NUM_VXRS];
extern cpumask_t cpu_setup_mask;
extern int __cpu_up(unsigned int cpu, struct task_struct *tidle);
extern void arch_send_call_function_single_ipi(int cpu);
extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
extern void smp_call_online_cpu(void (*func)(void *), void *);
extern void smp_call_ipl_cpu(void (*func)(void *), void *);
extern void smp_emergency_stop(void);
extern int smp_find_processor_id(u16 address);
extern int smp_store_status(int cpu);
extern void smp_save_dump_cpus(void);
extern void smp_yield_cpu(int cpu);
extern void smp_cpu_set_polarization(int cpu, int val);
extern int smp_cpu_get_polarization(int cpu);
extern int smp_cpu_get_cpu_address(int cpu);
extern void smp_fill_possible_mask(void);
extern void smp_detect_cpus(void);
static inline void smp_stop_cpu(void)
{
u16 pcpu = stap();
for (;;) {
__pcpu_sigp(pcpu, SIGP_STOP, 0, NULL);
cpu_relax();
}
}
/* Return thread 0 CPU number as base CPU */
static inline int smp_get_base_cpu(int cpu)
{
return cpu - (cpu % (smp_cpu_mtid + 1));
}
static inline void smp_cpus_done(unsigned int max_cpus)
{
}
extern int smp_rescan_cpus(void);
extern void __noreturn cpu_die(void);
extern void __cpu_die(unsigned int cpu);
extern int __cpu_disable(void);
extern void schedule_mcck_handler(void);
void notrace smp_yield_cpu(int cpu);
#endif /* __ASM_SMP_H */