powerpc/pseries: Update CPU hotplug error recovery

Update the cpu dlpar add/remove paths to do better error recovery when
a failure occurs during the add/remove operation.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Nathan Fontenot 2015-12-16 14:52:39 -06:00 committed by Michael Ellerman
parent d98389f375
commit e666ae0b10

View File

@ -18,6 +18,8 @@
* 2 of the License, or (at your option) any later version.
*/
#define pr_fmt(fmt) "pseries-hotplug-cpu: " fmt
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
@ -405,38 +407,67 @@ static bool dlpar_cpu_exists(struct device_node *parent, u32 drc_index)
static ssize_t dlpar_cpu_add(u32 drc_index)
{
struct device_node *dn, *parent;
int rc;
int rc, saved_rc;
pr_debug("Attempting to add CPU, drc index: %x\n", drc_index);
parent = of_find_node_by_path("/cpus");
if (!parent)
if (!parent) {
pr_warn("Failed to find CPU root node \"/cpus\"\n");
return -ENODEV;
}
if (dlpar_cpu_exists(parent, drc_index)) {
of_node_put(parent);
printk(KERN_WARNING "CPU with drc index %x already exists\n",
drc_index);
pr_warn("CPU with drc index %x already exists\n", drc_index);
return -EINVAL;
}
rc = dlpar_acquire_drc(drc_index);
if (rc) {
pr_warn("Failed to acquire DRC, rc: %d, drc index: %x\n",
rc, drc_index);
of_node_put(parent);
return -EINVAL;
}
dn = dlpar_configure_connector(cpu_to_be32(drc_index), parent);
of_node_put(parent);
if (!dn)
if (!dn) {
pr_warn("Failed call to configure-connector, drc index: %x\n",
drc_index);
dlpar_release_drc(drc_index);
return -EINVAL;
}
rc = dlpar_attach_node(dn);
if (rc) {
dlpar_release_drc(drc_index);
dlpar_free_cc_nodes(dn);
return rc;
saved_rc = rc;
pr_warn("Failed to attach node %s, rc: %d, drc index: %x\n",
dn->name, rc, drc_index);
rc = dlpar_release_drc(drc_index);
if (!rc)
dlpar_free_cc_nodes(dn);
return saved_rc;
}
rc = dlpar_online_cpu(dn);
if (rc) {
saved_rc = rc;
pr_warn("Failed to online cpu %s, rc: %d, drc index: %x\n",
dn->name, rc, drc_index);
rc = dlpar_detach_node(dn);
if (!rc)
dlpar_release_drc(drc_index);
return saved_rc;
}
pr_debug("Successfully added CPU %s, drc index: %x\n", dn->name,
drc_index);
return rc;
}
@ -500,19 +531,38 @@ static ssize_t dlpar_cpu_remove(struct device_node *dn, u32 drc_index)
{
int rc;
pr_debug("Attemping to remove CPU %s, drc index: %x\n",
dn->name, drc_index);
rc = dlpar_offline_cpu(dn);
if (rc)
if (rc) {
pr_warn("Failed to offline CPU %s, rc: %d\n", dn->name, rc);
return -EINVAL;
}
rc = dlpar_release_drc(drc_index);
if (rc)
if (rc) {
pr_warn("Failed to release drc (%x) for CPU %s, rc: %d\n",
drc_index, dn->name, rc);
dlpar_online_cpu(dn);
return rc;
}
rc = dlpar_detach_node(dn);
if (rc)
dlpar_acquire_drc(drc_index);
if (rc) {
int saved_rc = rc;
return rc;
pr_warn("Failed to detach CPU %s, rc: %d", dn->name, rc);
rc = dlpar_acquire_drc(drc_index);
if (!rc)
dlpar_online_cpu(dn);
return saved_rc;
}
pr_debug("Successfully removed CPU, drc index: %x\n", drc_index);
return 0;
}
#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE