x86: convert cpumask_of_cpu macro to allocated array
* Here is a simple patch to use an allocated array of cpumasks to
represent cpumask_of_cpu() instead of constructing one on the stack.
It's based on the Kconfig option "HAVE_CPUMASK_OF_CPU_MAP" which is
currently only set for x86_64 SMP. Otherwise the the existing
cpumask_of_cpu() is used but has been changed to produce an lvalue
so a pointer to it can be used.
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2a59dbb..7f30b75 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -117,6 +117,9 @@
config HAVE_SETUP_PER_CPU_AREA
def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
+config HAVE_CPUMASK_OF_CPU_MAP
+ def_bool X86_64_SMP
+
config ARCH_HIBERNATION_POSSIBLE
def_bool y
depends on !SMP || !X86_VOYAGER
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index ed157c9..0d1f44a 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -54,6 +54,24 @@
#endif
}
+#ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP
+cpumask_t *cpumask_of_cpu_map __read_mostly;
+EXPORT_SYMBOL(cpumask_of_cpu_map);
+
+/* requires nr_cpu_ids to be initialized */
+static void __init setup_cpumask_of_cpu(void)
+{
+ int i;
+
+ /* alloc_bootmem zeroes memory */
+ cpumask_of_cpu_map = alloc_bootmem_low(sizeof(cpumask_t) * nr_cpu_ids);
+ for (i = 0; i < nr_cpu_ids; i++)
+ cpu_set(i, cpumask_of_cpu_map[i]);
+}
+#else
+static inline void setup_cpumask_of_cpu(void) { }
+#endif
+
#ifdef CONFIG_X86_32
/*
* Great future not-so-futuristic plan: make i386 and x86_64 do it
@@ -70,7 +88,7 @@
*/
void __init setup_per_cpu_areas(void)
{
- int i;
+ int i, highest_cpu = 0;
unsigned long size;
#ifdef CONFIG_HOTPLUG_CPU
@@ -104,10 +122,18 @@
__per_cpu_offset[i] = ptr - __per_cpu_start;
#endif
memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
+
+ highest_cpu = i;
}
+ nr_cpu_ids = highest_cpu + 1;
+ printk(KERN_DEBUG "NR_CPUS: %d, nr_cpu_ids: %d\n", NR_CPUS, nr_cpu_ids);
+
/* Setup percpu data maps */
setup_per_cpu_maps();
+
+ /* Setup cpumask_of_cpu map */
+ setup_cpumask_of_cpu();
}
#endif