[PATCH v3 3/6] dcdbas: make use of smp_call_sync_on_phys_cpu()

From: Juergen Gross
Date: Fri Apr 01 2016 - 03:14:52 EST


Use smp_call_sync_on_phys_cpu() to raise SMI on cpu 0.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
drivers/firmware/dcdbas.c | 46 ++++++++++++++++++++--------------------------
1 file changed, 20 insertions(+), 26 deletions(-)

diff --git a/drivers/firmware/dcdbas.c b/drivers/firmware/dcdbas.c
index 829eec8..d15ad0b 100644
--- a/drivers/firmware/dcdbas.c
+++ b/drivers/firmware/dcdbas.c
@@ -238,33 +238,14 @@ 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;
+ struct smi_cmd *smi_cmd = par;

- if (smi_cmd->magic != SMI_CMD_MAGIC) {
- dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
- __func__);
- return -EBADR;
- }
-
- /* 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 */
@@ -280,10 +261,23 @@ int dcdbas_smi_request(struct smi_cmd *smi_cmd)
: "memory"
);

-out:
- set_cpus_allowed_ptr(current, old_mask);
- free_cpumask_var(old_mask);
- return ret;
+ return 0;
+}
+/**
+ * dcdbas_smi_request: generate SMI request
+ *
+ * Called with smi_data_lock.
+ */
+int dcdbas_smi_request(struct smi_cmd *smi_cmd)
+{
+ if (smi_cmd->magic != SMI_CMD_MAGIC) {
+ dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
+ __func__);
+ return -EBADR;
+ }
+
+ /* SMI requires CPU 0 */
+ return smp_call_sync_on_phys_cpu(0, raise_smi, smi_cmd);
}

/**
--
2.6.2