freebsd-skq/sys/ia64/include/smp.h
attilio e85ca71aad * Completely Remove the option STOP_NMI from the kernel. This option
has proven to have a good effect when entering KDB by using a NMI,
but it completely violates all the good rules about interrupts
disabled while holding a spinlock in other occasions.  This can be the
cause of deadlocks on events where a normal IPI_STOP is expected.
* Adds an new IPI called IPI_STOP_HARD on all the supported architectures.
This IPI is responsible for sending a stop message among CPUs using a
privileged channel when disponible. In other cases it just does match a
normal IPI_STOP.
Right now the IPI_STOP_HARD functionality uses a NMI on ia32 and amd64
architectures, while on the other has a normal IPI_STOP effect. It is
responsibility of maintainers to eventually implement an hard stop
when necessary and possible.
* Use the new IPI facility in order to implement a new userend SMP kernel
function called stop_cpus_hard(). That is specular to stop_cpu() but
it does use the privileged channel for the stopping facility.
* Let KDB use the newly introduced function stop_cpus_hard() and leave
stop_cpus() for all the other cases
* Disable interrupts on CPU0 when starting the process of APs suspension.
* Style cleanup and comments adding

This patch should fix the reboot/shutdown deadlocks many users are
constantly reporting on mailing lists.

Please don't forget to update your config file with the STOP_NMI
option removal

Reviewed by:	jhb
Tested by:	pho, bz, rink
Approved by:	re (kib)
2009-08-13 17:09:45 +00:00

42 lines
881 B
C

/*
* $FreeBSD$
*/
#ifndef _MACHINE_SMP_H_
#define _MACHINE_SMP_H_
#ifdef _KERNEL
/*
* Interprocessor interrupts for SMP. The following values are indices
* into the IPI vector table. The SAL gives us the vector used for AP
* wake-up. We base the other vectors on that. Keep IPI_AP_WAKEUP at
* index 0. See sal.c for details.
*/
/* Architecture specific IPIs. */
#define IPI_AP_WAKEUP 0
#define IPI_HIGH_FP 1
#define IPI_MCA_CMCV 2
#define IPI_MCA_RENDEZ 3
/* Machine independent IPIs. */
#define IPI_AST 4
#define IPI_RENDEZVOUS 5
#define IPI_STOP 6
#define IPI_STOP_HARD 6
#define IPI_PREEMPT 7
#define IPI_COUNT 8
#ifndef LOCORE
struct pcpu;
extern int ipi_vector[];
void ipi_all_but_self(int ipi);
void ipi_selected(cpumask_t cpus, int ipi);
void ipi_send(struct pcpu *, int ipi);
#endif /* !LOCORE */
#endif /* _KERNEL */
#endif /* !_MACHINE_SMP_H */