X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fcpu.c;h=e202a68d1cc180cf62ade78b025ec2329c8aabcd;hb=987c402ac31988f7ecdb38b657bcfeea5831d479;hp=29510d68338a3ef7bfd80def013f8f15f650155e;hpb=eeec4fad963490821348a331cca6102ae1c4a7a3;p=linux-2.6

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 29510d6833..e202a68d1c 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -455,3 +455,28 @@ out:
 #endif /* CONFIG_PM_SLEEP_SMP */
 
 #endif /* CONFIG_SMP */
+
+/*
+ * cpu_bit_bitmap[] is a special, "compressed" data structure that
+ * represents all NR_CPUS bits binary values of 1<<nr.
+ *
+ * It is used by cpumask_of_cpu() to get a constant address to a CPU
+ * mask value that has a single bit set only.
+ */
+
+/* cpu_bit_bitmap[0] is empty - so we can back into it */
+#define MASK_DECLARE_1(x)	[x+1][0] = 1UL << (x)
+#define MASK_DECLARE_2(x)	MASK_DECLARE_1(x), MASK_DECLARE_1(x+1)
+#define MASK_DECLARE_4(x)	MASK_DECLARE_2(x), MASK_DECLARE_2(x+2)
+#define MASK_DECLARE_8(x)	MASK_DECLARE_4(x), MASK_DECLARE_4(x+4)
+
+const unsigned long cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)] = {
+
+	MASK_DECLARE_8(0),	MASK_DECLARE_8(8),
+	MASK_DECLARE_8(16),	MASK_DECLARE_8(24),
+#if BITS_PER_LONG > 32
+	MASK_DECLARE_8(32),	MASK_DECLARE_8(40),
+	MASK_DECLARE_8(48),	MASK_DECLARE_8(56),
+#endif
+};
+EXPORT_SYMBOL_GPL(cpu_bit_bitmap);