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/include/linux/cpumask.h b/include/linux/cpumask.h
index 629102f..259c805 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -222,8 +222,13 @@
#define next_cpu(n, src) ({ (void)(src); 1; })
#endif
+#ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP
+extern cpumask_t *cpumask_of_cpu_map;
+#define cpumask_of_cpu(cpu) (cpumask_of_cpu_map[cpu])
+
+#else
#define cpumask_of_cpu(cpu) \
-({ \
+(*({ \
typeof(_unused_cpumask_arg_) m; \
if (sizeof(m) == sizeof(unsigned long)) { \
m.bits[0] = 1UL<<(cpu); \
@@ -231,8 +236,9 @@
cpus_clear(m); \
cpu_set((cpu), m); \
} \
- m; \
-})
+ &m; \
+}))
+#endif
#define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS)