/*
* This runs only on the current cpu. We try to find an LVT offset and
* setup the local APIC. For this we must disable preemption. On
* success we initialize all nodes with this offset. This updates then
* the offset in the IBS_CTL per-node msr. The per-core APIC setup of
* the IBS interrupt vector is handled by perf_ibs_cpu_notifier that
* is using the new offset.
*/
static void force_ibs_eilvt_setup(void)
{
int offset;
int ret;
preempt_disable();
/* find the next free available EILVT entry, skip offset 0 */
for (offset = 1; offset < APIC_EILVT_NR_MAX; offset++) {
if (get_eilvt(offset))
break;
}
preempt_enable();
if (offset == APIC_EILVT_NR_MAX) {
printk(KERN_DEBUG "No EILVT entry available\n");
return;
}
ret = setup_ibs_ctl(offset);
if (ret)
goto out;
if (!ibs_eilvt_valid())
goto out;
pr_info("IBS: LVT offset %d assigned\n", offset);
return;
out:
preempt_disable();
put_eilvt(offset);
preempt_enable();
return;
}
static __init int amd_ibs_init(void)
{
u32 caps;
int ret = -EINVAL;
caps = __get_ibs_caps();
if (!caps)
return -ENODEV; /* ibs not supported by the cpu */
ibs_eilvt_setup();
if (!ibs_eilvt_valid())
goto out;
perf_ibs_pm_init();
cpu_notifier_register_begin();
ibs_caps = caps;
/* make ibs_caps visible to other cpus: */
smp_mb();
smp_call_function(setup_APIC_ibs, NULL, 1);
__perf_cpu_notifier(perf_ibs_cpu_notifier);
cpu_notifier_register_done();
ret = perf_event_ibs_init();
out:
if (ret)
pr_err("Failed to setup IBS, %d\n", ret);
return ret;
}
static __init int amd_ibs_init(void)
{
u32 caps;
int ret = -EINVAL;
caps = __get_ibs_caps();
if (!caps)
return -ENODEV; /* ibs not supported by the cpu */
/*
* Force LVT offset assignment for family 10h: The offsets are
* not assigned by the BIOS for this family, so the OS is
* responsible for doing it. If the OS assignment fails, fall
* back to BIOS settings and try to setup this.
*/
if (boot_cpu_data.x86 == 0x10)
force_ibs_eilvt_setup();
if (!ibs_eilvt_valid())
goto out;
get_online_cpus();
ibs_caps = caps;
/* make ibs_caps visible to other cpus: */
smp_mb();
perf_cpu_notifier(perf_ibs_cpu_notifier);
smp_call_function(setup_APIC_ibs, NULL, 1);
put_online_cpus();
ret = perf_event_ibs_init();
out:
if (ret)
pr_err("Failed to setup IBS, %d\n", ret);
return ret;
}
