powerpc/cacheinfo: add cacheinfo_teardown, cacheinfo_rebuild
Allow external callers to force the cacheinfo code to release all its
references to cache nodes, e.g. before processing device tree updates
post-migration, and to rebuild the hierarchy afterward.
CPU online/offline must be blocked by callers; enforce this.
Fixes: 410bccf97881 ("powerpc/pseries: Partition migration in the kernel")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/kernel/cacheinfo.c b/arch/powerpc/kernel/cacheinfo.c
index 862e289..42c559ef 100644
--- a/arch/powerpc/kernel/cacheinfo.c
+++ b/arch/powerpc/kernel/cacheinfo.c
@@ -896,4 +896,25 @@ void cacheinfo_cpu_offline(unsigned int cpu_id)
if (cache)
cache_cpu_clear(cache, cpu_id);
}
+
+void cacheinfo_teardown(void)
+{
+ unsigned int cpu;
+
+ lockdep_assert_cpus_held();
+
+ for_each_online_cpu(cpu)
+ cacheinfo_cpu_offline(cpu);
+}
+
+void cacheinfo_rebuild(void)
+{
+ unsigned int cpu;
+
+ lockdep_assert_cpus_held();
+
+ for_each_online_cpu(cpu)
+ cacheinfo_cpu_online(cpu);
+}
+
#endif /* (CONFIG_PPC_PSERIES && CONFIG_SUSPEND) || CONFIG_HOTPLUG_CPU */
