powerpc/pseries: Factor out common cpu hotplug code

Re-factor the cpu hotplug code to support doing cpu hotplug completely in
the kernel and using the existing sysfs probe/release interfaces. This
patch pulls out pieces of existing cpu hotplug code into common routines,
dlpar_cpu_add() and dlpar_cpu_remove(), to be used by both interfaces.
There are no functional changes introduced.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
index 66d8c2c64aa9ba572036ed6cc6a0b445addad110..6fb28cf229e7e96ebcff9e6e5b9d29d7e288fae2 100644 (file)
--- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -335,8 +335,6 @@ static void pseries_remove_processor(struct device_node *np)
        cpu_maps_update_done();
 }
 
-#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
-
 static int dlpar_online_cpu(struct device_node *dn)
 {
        int rc = 0;
@@ -404,16 +402,11 @@ static bool dlpar_cpu_exists(struct device_node *parent, u32 drc_index)
        return found;
 }
 
-static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
+static ssize_t dlpar_cpu_add(u32 drc_index)
 {
        struct device_node *dn, *parent;
-       u32 drc_index;
        int rc;
 
-       rc = kstrtou32(buf, 0, &drc_index);
-       if (rc)
-               return -EINVAL;
-
        parent = of_find_node_by_path("/cpus");
        if (!parent)
                return -ENODEV;
@@ -444,10 +437,7 @@ static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
        }
 
        rc = dlpar_online_cpu(dn);
-       if (rc)
-               return rc;
-
-       return count;
+       return rc;
 }
 
 static int dlpar_offline_cpu(struct device_node *dn)
@@ -506,6 +496,41 @@ out:
 
 }
 
+static ssize_t dlpar_cpu_remove(struct device_node *dn, u32 drc_index)
+{
+       int rc;
+
+       rc = dlpar_offline_cpu(dn);
+       if (rc)
+               return -EINVAL;
+
+       rc = dlpar_release_drc(drc_index);
+       if (rc)
+               return rc;
+
+       rc = dlpar_detach_node(dn);
+       if (rc)
+               dlpar_acquire_drc(drc_index);
+
+       return rc;
+}
+
+#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
+
+static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
+{
+       u32 drc_index;
+       int rc;
+
+       rc = kstrtou32(buf, 0, &drc_index);
+       if (rc)
+               return -EINVAL;
+
+       rc = dlpar_cpu_add(drc_index);
+
+       return rc ? rc : count;
+}
+
 static ssize_t dlpar_cpu_release(const char *buf, size_t count)
 {
        struct device_node *dn;
@@ -522,27 +547,10 @@ static ssize_t dlpar_cpu_release(const char *buf, size_t count)
                return -EINVAL;
        }
 
-       rc = dlpar_offline_cpu(dn);
-       if (rc) {
-               of_node_put(dn);
-               return -EINVAL;
-       }
-
-       rc = dlpar_release_drc(drc_index);
-       if (rc) {
-               of_node_put(dn);
-               return rc;
-       }
-
-       rc = dlpar_detach_node(dn);
-       if (rc) {
-               dlpar_acquire_drc(drc_index);
-               return rc;
-       }
-
+       rc = dlpar_cpu_remove(dn, drc_index);
        of_node_put(dn);
 
-       return count;
+       return rc ? rc : count;
 }
 
 #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */