diff options
Diffstat (limited to 'arch/ia64/kernel/mca.c')
| -rw-r--r-- | arch/ia64/kernel/mca.c | 60 |
1 files changed, 53 insertions, 7 deletions
diff --git a/arch/ia64/kernel/mca.c b/arch/ia64/kernel/mca.c index 1ead5ea6c5c..4b5daa3cc0f 100644 --- a/arch/ia64/kernel/mca.c +++ b/arch/ia64/kernel/mca.c @@ -57,6 +57,9 @@ * * 2006-09-15 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> * Add printing support for MCA/INIT. + * + * 2007-04-27 Russ Anderson <rja@sgi.com> + * Support multiple cpus going through OS_MCA in the same event. */ #include <linux/types.h> #include <linux/init.h> @@ -96,7 +99,6 @@ #endif /* Used by mca_asm.S */ -u32 ia64_mca_serialize; DEFINE_PER_CPU(u64, ia64_mca_data); /* == __per_cpu_mca[smp_processor_id()] */ DEFINE_PER_CPU(u64, ia64_mca_per_cpu_pte); /* PTE to map per-CPU area */ DEFINE_PER_CPU(u64, ia64_mca_pal_pte); /* PTE to map PAL code */ @@ -963,11 +965,12 @@ ia64_mca_modify_original_stack(struct pt_regs *regs, goto no_mod; } + if (r13 != sos->prev_IA64_KR_CURRENT) { + msg = "inconsistent previous current and r13"; + goto no_mod; + } + if (!mca_recover_range(ms->pmsa_iip)) { - if (r13 != sos->prev_IA64_KR_CURRENT) { - msg = "inconsistent previous current and r13"; - goto no_mod; - } if ((r12 - r13) >= KERNEL_STACK_SIZE) { msg = "inconsistent r12 and r13"; goto no_mod; @@ -1187,6 +1190,13 @@ all_in: * further MCA logging is enabled by clearing logs. * Monarch also has the duty of sending wakeup-IPIs to pull the * slave processors out of rendezvous spinloop. + * + * If multiple processors call into OS_MCA, the first will become + * the monarch. Subsequent cpus will be recorded in the mca_cpu + * bitmask. After the first monarch has processed its MCA, it + * will wake up the next cpu in the mca_cpu bitmask and then go + * into the rendezvous loop. When all processors have serviced + * their MCA, the last monarch frees up the rest of the processors. */ void ia64_mca_handler(struct pt_regs *regs, struct switch_stack *sw, @@ -1196,16 +1206,32 @@ ia64_mca_handler(struct pt_regs *regs, struct switch_stack *sw, struct task_struct *previous_current; struct ia64_mca_notify_die nd = { .sos = sos, .monarch_cpu = &monarch_cpu }; + static atomic_t mca_count; + static cpumask_t mca_cpu; + if (atomic_add_return(1, &mca_count) == 1) { + monarch_cpu = cpu; + sos->monarch = 1; + } else { + cpu_set(cpu, mca_cpu); + sos->monarch = 0; + } mprintk(KERN_INFO "Entered OS MCA handler. PSP=%lx cpu=%d " "monarch=%ld\n", sos->proc_state_param, cpu, sos->monarch); previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "MCA"); - monarch_cpu = cpu; + if (notify_die(DIE_MCA_MONARCH_ENTER, "MCA", regs, (long)&nd, 0, 0) == NOTIFY_STOP) ia64_mca_spin(__FUNCTION__); - ia64_wait_for_slaves(cpu, "MCA"); + if (sos->monarch) { + ia64_wait_for_slaves(cpu, "MCA"); + } else { + ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_CONCURRENT_MCA; + while (cpu_isset(cpu, mca_cpu)) + cpu_relax(); /* spin until monarch wakes us */ + ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE; + } /* Wakeup all the processors which are spinning in the rendezvous loop. * They will leave SAL, then spin in the OS with interrupts disabled @@ -1244,6 +1270,26 @@ ia64_mca_handler(struct pt_regs *regs, struct switch_stack *sw, == NOTIFY_STOP) ia64_mca_spin(__FUNCTION__); + + if (atomic_dec_return(&mca_count) > 0) { + int i; + + /* wake up the next monarch cpu, + * and put this cpu in the rendez loop. + */ + ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_CONCURRENT_MCA; + for_each_online_cpu(i) { + if (cpu_isset(i, mca_cpu)) { + monarch_cpu = i; + cpu_clear(i, mca_cpu); /* wake next cpu */ + while (monarch_cpu != -1) + cpu_relax(); /* spin until last cpu leaves */ + ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE; + set_curr_task(cpu, previous_current); + return; + } + } + } set_curr_task(cpu, previous_current); monarch_cpu = -1; } |