xen/arm: implement smp_call_function

Move smp_call_function and on_selected_cpus to common code.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Keir Fraser <keir@xen.org>

1 files changed, 112 insertions, 0 deletions

diff --git a/xen/common/smp.c b/xen/common/smp.c
new file mode 100644
index 0000000000..b2b056b5e5
--- /dev/null
+++ b/xen/common/smp.c
@@ -0,0 +1,112 @@
+/*
+ * xen/common/smp.c
+ *
+ * Generic SMP function
+ *
+ * Copyright (c) 2013 Citrix Systems.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <asm/hardirq.h>
+#include <asm/processor.h>
+#include <xen/spinlock.h>
+#include <xen/smp.h>
+
+/*
+ * Structure and data for smp_call_function()/on_selected_cpus().
+ */
+static DEFINE_SPINLOCK(call_lock);
+static struct call_data_struct {
+    void (*func) (void *info);
+    void *info;
+    int wait;
+    cpumask_t selected;
+} call_data;
+
+void smp_call_function(
+    void (*func) (void *info),
+    void *info,
+    int wait)
+{
+    cpumask_t allbutself;
+
+    cpumask_andnot(&allbutself, &cpu_online_map,
+                   cpumask_of(smp_processor_id()));
+    on_selected_cpus(&allbutself, func, info, wait);
+}
+
+void on_selected_cpus(
+    const cpumask_t *selected,
+    void (*func) (void *info),
+    void *info,
+    int wait)
+{
+    unsigned int nr_cpus;
+
+    ASSERT(local_irq_is_enabled());
+
+    spin_lock(&call_lock);
+
+    cpumask_copy(&call_data.selected, selected);
+
+    nr_cpus = cpumask_weight(&call_data.selected);
+    if ( nr_cpus == 0 )
+        goto out;
+
+    call_data.func = func;
+    call_data.info = info;
+    call_data.wait = wait;
+
+    smp_send_call_function_mask(&call_data.selected);
+
+    while ( !cpumask_empty(&call_data.selected) )
+        cpu_relax();
+
+out:
+    spin_unlock(&call_lock);
+}
+
+void smp_call_function_interrupt(void)
+{
+    void (*func)(void *info) = call_data.func;
+    void *info = call_data.info;
+    unsigned int cpu = smp_processor_id();
+
+    if ( !cpumask_test_cpu(cpu, &call_data.selected) )
+        return;
+
+    irq_enter();
+
+    if ( call_data.wait )
+    {
+        (*func)(info);
+        mb();
+        cpumask_clear_cpu(cpu, &call_data.selected);
+    }
+    else
+    {
+        mb();
+        cpumask_clear_cpu(cpu, &call_data.selected);
+        (*func)(info);
+    }
+
+    irq_exit();
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */