Merge branch 'core-smp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull core SMP updates from Ingo Molnar:
 "Two main change is generic vCPU pinning and physical CPU SMP-call
  support, for Xen to be able to perform certain calls on specific
  physical CPUs - by Juergen Gross"

* 'core-smp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp: Allocate smp_call_on_cpu() workqueue on stack too
  hwmon: Use smp_call_on_cpu() for dell-smm i8k
  dcdbas: Make use of smp_call_on_cpu()
  xen: Add xen_pin_vcpu() to support calling functions on a dedicated pCPU
  smp: Add function to execute a function synchronously on a CPU
  virt, sched: Add generic vCPU pinning support
  xen: Sync xen header

1 files changed, 26 insertions, 25 deletions

diff --git a/drivers/firmware/dcdbas.c b/drivers/firmware/dcdbas.c
index 829eec8959f2..2fe1a130189f 100644
--- a/drivers/firmware/dcdbas.c
+++ b/drivers/firmware/dcdbas.c
@@ -23,6 +23,7 @@
 #include <linux/platform_device.h>
 #include <linux/dma-mapping.h>
 #include <linux/errno.h>
+#include <linux/cpu.h>
 #include <linux/gfp.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
@@ -238,33 +239,14 @@ static ssize_t host_control_on_shutdown_store(struct device *dev,
         return count;
 }
 
-/**
- * dcdbas_smi_request: generate SMI request
- *
- * Called with smi_data_lock.
- */
-int dcdbas_smi_request(struct smi_cmd *smi_cmd)
+static int raise_smi(void *par)
 {
-        cpumask_var_t old_mask;
-        int ret = 0;
-
-        if (smi_cmd->magic != SMI_CMD_MAGIC) {
-                dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
-                         __func__);
-                return -EBADR;
-        }
+        struct smi_cmd *smi_cmd = par;
 
-        /* SMI requires CPU 0 */
-        if (!alloc_cpumask_var(&old_mask, GFP_KERNEL))
-                return -ENOMEM;
-
-        cpumask_copy(old_mask, &current->cpus_allowed);
-        set_cpus_allowed_ptr(current, cpumask_of(0));
         if (smp_processor_id() != 0) {
                 dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n",
                         __func__);
-                ret = -EBUSY;
-                goto out;
+                return -EBUSY;
         }
 
         /* generate SMI */
@@ -280,9 +262,28 @@ int dcdbas_smi_request(struct smi_cmd *smi_cmd)
                 : "memory"
         );
 
-out:
-        set_cpus_allowed_ptr(current, old_mask);
-        free_cpumask_var(old_mask);
+        return 0;
+}
+/**
+ * dcdbas_smi_request: generate SMI request
+ *
+ * Called with smi_data_lock.
+ */
+int dcdbas_smi_request(struct smi_cmd *smi_cmd)
+{
+        int ret;
+
+        if (smi_cmd->magic != SMI_CMD_MAGIC) {
+                dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
+                         __func__);
+                return -EBADR;
+        }
+
+        /* SMI requires CPU 0 */
+        get_online_cpus();
+        ret = smp_call_on_cpu(0, raise_smi, smi_cmd, true);
+        put_online_cpus();
+
         return ret;
 }