pseries/pseries: Add code to online/offline CPUs of a DLPAR node

Currently the cpu-allocation/deallocation on pSeries is a
two step process from the Userspace.

- Set the indicators and update the device tree by writing to the sysfs
  tunable "probe" during allocation and "release" during deallocation.
- Online / Offline the CPUs of the allocated/would_be_deallocated node by
  writing to the sysfs tunable "online".

This patch adds kernel code to online/offline the CPUs soon_after/just_before
they have been allocated/would_be_deallocated. This way, the userspace tool
that performs DLPAR operations would only have to deal with one set of sysfs
tunables namely "probe" and release".

Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Acked-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Gautham R Shenoy 2009-11-26 09:58:55 +00:00 committed by Benjamin Herrenschmidt
parent 8389b37dff
commit b6db63d1a7

View file

@ -16,6 +16,7 @@
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/cpu.h>
#include "offline_states.h"
#include <asm/prom.h>
#include <asm/machdep.h>
@ -287,6 +288,98 @@ int dlpar_detach_node(struct device_node *dn)
return 0;
}
int online_node_cpus(struct device_node *dn)
{
int rc = 0;
unsigned int cpu;
int len, nthreads, i;
const u32 *intserv;
intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
if (!intserv)
return -EINVAL;
nthreads = len / sizeof(u32);
cpu_maps_update_begin();
for (i = 0; i < nthreads; i++) {
for_each_present_cpu(cpu) {
if (get_hard_smp_processor_id(cpu) != intserv[i])
continue;
BUG_ON(get_cpu_current_state(cpu)
!= CPU_STATE_OFFLINE);
cpu_maps_update_done();
rc = cpu_up(cpu);
if (rc)
goto out;
cpu_maps_update_begin();
break;
}
if (cpu == num_possible_cpus())
printk(KERN_WARNING "Could not find cpu to online "
"with physical id 0x%x\n", intserv[i]);
}
cpu_maps_update_done();
out:
return rc;
}
int offline_node_cpus(struct device_node *dn)
{
int rc = 0;
unsigned int cpu;
int len, nthreads, i;
const u32 *intserv;
intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
if (!intserv)
return -EINVAL;
nthreads = len / sizeof(u32);
cpu_maps_update_begin();
for (i = 0; i < nthreads; i++) {
for_each_present_cpu(cpu) {
if (get_hard_smp_processor_id(cpu) != intserv[i])
continue;
if (get_cpu_current_state(cpu) == CPU_STATE_OFFLINE)
break;
if (get_cpu_current_state(cpu) == CPU_STATE_ONLINE) {
cpu_maps_update_done();
rc = cpu_down(cpu);
if (rc)
goto out;
cpu_maps_update_begin();
break;
}
/*
* The cpu is in CPU_STATE_INACTIVE.
* Upgrade it's state to CPU_STATE_OFFLINE.
*/
set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
BUG_ON(plpar_hcall_norets(H_PROD, intserv[i])
!= H_SUCCESS);
__cpu_die(cpu);
break;
}
if (cpu == num_possible_cpus())
printk(KERN_WARNING "Could not find cpu to offline "
"with physical id 0x%x\n", intserv[i]);
}
cpu_maps_update_done();
out:
return rc;
}
#define DR_ENTITY_SENSE 9003
#define DR_ENTITY_PRESENT 1
#define DR_ENTITY_UNUSABLE 2
@ -385,6 +478,8 @@ static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
dlpar_free_cc_nodes(dn);
}
rc = online_node_cpus(dn);
return rc ? rc : count;
}
@ -404,6 +499,12 @@ static ssize_t dlpar_cpu_release(const char *buf, size_t count)
return -EINVAL;
}
rc = offline_node_cpus(dn);
if (rc) {
of_node_put(dn);
return -EINVAL;
}
rc = dlpar_release_drc(*drc_index);
if (rc) {
of_node_put(dn);