[PATCH] 2.5.32: is_smp() and can_be_smp()

From: Luca Barbieri (ldb@ldb.ods.org)
Date: Tue Aug 27 2002 - 17:07:27 EST

Will be used by another patch that I'll post in the very near future.
For i386 cpucount is used rather than computing the hweight of
cpu_online_map since it's faster and already there.
Ideally the same should be done for all architectures in both these
macros and num_online_cpus and num_possible_cpus.

diff --exclude-from=/home/ldb/src/linux-exclude -urNdp linux-2.5.32/include/asm-i386/smp.h linux-2.5.32_smp/include/asm-i386/smp.h
--- linux-2.5.32/include/asm-i386/smp.h 2002-08-27 21:26:32.000000000 +0200
+++ linux-2.5.32_smp/include/asm-i386/smp.h 2002-08-27 23:25:09.000000000 +0200
@@ -94,6 +94,10 @@ extern inline unsigned int num_online_cp
         return hweight32(cpu_online_map);
 }
 
+extern int cpucount;
+#define is_smp() (cpucount)
+#define can_be_smp() (cpucount)
+
 extern inline int any_online_cpu(unsigned int mask)
 {
         if (mask & cpu_online_map)
diff --exclude-from=/home/ldb/src/linux-exclude -urNdp linux-2.5.32/include/linux/smp.h linux-2.5.32_smp/include/linux/smp.h
--- linux-2.5.32/include/linux/smp.h 2002-08-27 21:26:43.000000000 +0200
+++ linux-2.5.32_smp/include/linux/smp.h 2002-08-27 23:25:47.000000000 +0200
@@ -78,6 +78,19 @@ extern int register_cpu_notifier(struct
 extern void unregister_cpu_notifier(struct notifier_block *nb);
 
 int cpu_up(unsigned int cpu);
+
+#ifndef is_smp
+#define is_smp() (num_online_cpus() > 1)
+#endif
+
+#ifndef can_be_smp
+#ifdef num_possible_cpus
+#define can_be_smp() (num_possible_cpus() > 1)
+#else
+#define can_be_smp() is_smp()
+#endif
+#endif
+
 #else /* !SMP */
 
 /*
@@ -96,6 +109,8 @@ static inline void smp_send_reschedule_a
 #define cpu_online_map 1
 #define cpu_online(cpu) ({ cpu; 1; })
 #define num_online_cpus() 1
+#define is_smp() 0
+#define can_be_smp() 0
 #define num_booting_cpus() 1
 
 struct notifier_block;


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This archive was generated by hypermail 2b29 : Sat Aug 31 2002 - 22:00:20 EST