The presence or absence of EBB is advertised to userspace via the presence
or absence of PPC_FEATURE2_EBB in cpu_user_features2.
Because the kernel can be built without PMU support, we should only add
PPC_FEATURE2_EBB to cpu_user_features2 when we successfully register the
power8 PMU support.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
static int __init init_power8_pmu(void)
{
+ int rc;
+
if (!cur_cpu_spec->oprofile_cpu_type ||
strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power8"))
return -ENODEV;
- return register_power_pmu(&power8_pmu);
+ rc = register_power_pmu(&power8_pmu);
+ if (rc)
+ return rc;
+
+ /* Tell userspace that EBB is supported */
+ cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_EBB;
+
+ return 0;
}
early_initcall(init_power8_pmu);