forked from luck/tmp_suning_uos_patched
67664c8f7e
This patch introduces a startup parameter no_broadcast. When we enable CONFIG_HOTPLUG_CPU, we dont want to use broadcast shortcut as it has ill effects on a offline cpu. If we issue broadcast, the IPI is also delivered to offline cpus, or partially up cpu causing stale IPI's to be handled, which is a problem and can cause undesirable effects. Introduces a new startup cmdline option no_ipi_broadcast, that can be switched at cmdline if necessary. Signed-off-by: Ashok Raj <ashok.raj@intel.com> Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
54 lines
1.1 KiB
C
54 lines
1.1 KiB
C
#ifndef __ASM_MACH_IPI_H
|
|
#define __ASM_MACH_IPI_H
|
|
|
|
void send_IPI_mask_bitmask(cpumask_t mask, int vector);
|
|
void __send_IPI_shortcut(unsigned int shortcut, int vector);
|
|
|
|
extern int no_broadcast;
|
|
|
|
static inline void send_IPI_mask(cpumask_t mask, int vector)
|
|
{
|
|
send_IPI_mask_bitmask(mask, vector);
|
|
}
|
|
|
|
static inline void __local_send_IPI_allbutself(int vector)
|
|
{
|
|
if (no_broadcast) {
|
|
cpumask_t mask = cpu_online_map;
|
|
int this_cpu = get_cpu();
|
|
|
|
cpu_clear(this_cpu, mask);
|
|
send_IPI_mask(mask, vector);
|
|
put_cpu();
|
|
} else
|
|
__send_IPI_shortcut(APIC_DEST_ALLBUT, vector);
|
|
}
|
|
|
|
static inline void __local_send_IPI_all(int vector)
|
|
{
|
|
if (no_broadcast)
|
|
send_IPI_mask(cpu_online_map, vector);
|
|
else
|
|
__send_IPI_shortcut(APIC_DEST_ALLINC, vector);
|
|
}
|
|
|
|
static inline void send_IPI_allbutself(int vector)
|
|
{
|
|
/*
|
|
* if there are no other CPUs in the system then we get an APIC send
|
|
* error if we try to broadcast, thus avoid sending IPIs in this case.
|
|
*/
|
|
if (!(num_online_cpus() > 1))
|
|
return;
|
|
|
|
__local_send_IPI_allbutself(vector);
|
|
return;
|
|
}
|
|
|
|
static inline void send_IPI_all(int vector)
|
|
{
|
|
__local_send_IPI_all(vector);
|
|
}
|
|
|
|
#endif /* __ASM_MACH_IPI_H */
|