[PATCH] Change any_online_cpu()

Rusty Russell (rusty@rustcorp.com.au)
Sat, 07 Jun 2003 16:16:13 +1000


Linus, please apply.

Noone calls it yet, but Matt Fleming points out that returning int
from any_online_cpu where cpu numbers are passed as unsigned ints
elsewhere is awkward and a little dangerous.

Make any_online_cpu() match find_first_bit(), by returning NR_CPUS
when no cpu is found, rather than -1. This also simplifies the future
case where NR_CPUS > BITS_PER_LONG.

Thanks,
Rusty.

--
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.

diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.70-bk11/include/asm-i386/smp.h working-2.5.70-bk11-tmp/include/asm-i386/smp.h --- linux-2.5.70-bk11/include/asm-i386/smp.h 2003-06-07 15:22:56.000000000 +1000 +++ working-2.5.70-bk11-tmp/include/asm-i386/smp.h 2003-06-07 16:05:01.000000000 +1000 @@ -78,12 +78,12 @@ static inline int num_booting_cpus(void) extern void map_cpu_to_logical_apicid(void); extern void unmap_cpu_to_logical_apicid(int cpu); -extern inline int any_online_cpu(unsigned int mask) +extern inline unsigned int any_online_cpu(unsigned int mask) { if (mask & cpu_online_map) return __ffs(mask & cpu_online_map); - return -1; + return NR_CPUS; } #ifdef CONFIG_X86_LOCAL_APIC diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.70-bk11/include/asm-ia64/smp.h working-2.5.70-bk11-tmp/include/asm-ia64/smp.h --- linux-2.5.70-bk11/include/asm-ia64/smp.h 2003-06-07 15:22:56.000000000 +1000 +++ working-2.5.70-bk11-tmp/include/asm-ia64/smp.h 2003-06-07 16:07:09.000000000 +1000 @@ -56,12 +56,12 @@ num_online_cpus (void) return hweight64(cpu_online_map); } -static inline int +static inline unsigned int any_online_cpu (unsigned int mask) { if (mask & cpu_online_map) return __ffs(mask & cpu_online_map); - return -1; + return NR_CPUS; } /* diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.70-bk11/include/asm-parisc/smp.h working-2.5.70-bk11-tmp/include/asm-parisc/smp.h --- linux-2.5.70-bk11/include/asm-parisc/smp.h 2003-02-11 14:26:16.000000000 +1100 +++ working-2.5.70-bk11-tmp/include/asm-parisc/smp.h 2003-06-07 16:07:21.000000000 +1000 @@ -60,12 +60,12 @@ extern inline unsigned int num_online_cp return hweight32(cpu_online_map); } -extern inline int any_online_cpu(unsigned int mask) +extern inline unsigned int any_online_cpu(unsigned int mask) { if (mask & cpu_online_map) return __ffs(mask & cpu_online_map); - return -1; + return NR_CPUS; } #endif /* CONFIG_SMP */ diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.70-bk11/include/asm-ppc/smp.h working-2.5.70-bk11-tmp/include/asm-ppc/smp.h --- linux-2.5.70-bk11/include/asm-ppc/smp.h 2003-01-02 12:27:50.000000000 +1100 +++ working-2.5.70-bk11-tmp/include/asm-ppc/smp.h 2003-06-07 16:07:27.000000000 +1000 @@ -53,12 +53,12 @@ extern inline unsigned int num_online_cp return hweight32(cpu_online_map); } -extern inline int any_online_cpu(unsigned int mask) +extern inline unsigned int any_online_cpu(unsigned int mask) { if (mask & cpu_online_map) return __ffs(mask & cpu_online_map); - return -1; + return NR_CPUS; } extern int __cpu_up(unsigned int cpu); diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.70-bk11/include/asm-s390/smp.h working-2.5.70-bk11-tmp/include/asm-s390/smp.h --- linux-2.5.70-bk11/include/asm-s390/smp.h 2003-04-20 18:05:13.000000000 +1000 +++ working-2.5.70-bk11-tmp/include/asm-s390/smp.h 2003-06-07 16:07:35.000000000 +1000 @@ -59,12 +59,12 @@ extern inline unsigned int num_online_cp #endif /* __s390x__ */ } -extern inline int any_online_cpu(unsigned int mask) +extern inline unsigned int any_online_cpu(unsigned int mask) { if (mask & cpu_online_map) return __ffs(mask & cpu_online_map); - return -1; + return NR_CPUS; } extern __inline__ __u16 hard_smp_processor_id(void) diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.70-bk11/include/asm-sparc64/smp.h working-2.5.70-bk11-tmp/include/asm-sparc64/smp.h --- linux-2.5.70-bk11/include/asm-sparc64/smp.h 2003-02-07 19:20:43.000000000 +1100 +++ working-2.5.70-bk11-tmp/include/asm-sparc64/smp.h 2003-06-07 16:07:42.000000000 +1000 @@ -80,11 +80,11 @@ extern atomic_t sparc64_num_cpus_online; extern atomic_t sparc64_num_cpus_possible; #define num_possible_cpus() (atomic_read(&sparc64_num_cpus_possible)) -static inline int any_online_cpu(unsigned long mask) +static inline unsigned int any_online_cpu(unsigned long mask) { if ((mask &= cpu_online_map) != 0UL) return __ffs(mask); - return -1; + return NR_CPUS; } /* diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.70-bk11/include/asm-x86_64/smp.h working-2.5.70-bk11-tmp/include/asm-x86_64/smp.h --- linux-2.5.70-bk11/include/asm-x86_64/smp.h 2003-06-07 15:22:57.000000000 +1000 +++ working-2.5.70-bk11-tmp/include/asm-x86_64/smp.h 2003-06-07 16:07:54.000000000 +1000 @@ -64,12 +64,12 @@ extern volatile unsigned long cpu_callou cpu = __ffs(mask), mask != 0; \ mask &= ~(1UL<<cpu)) -extern inline int any_online_cpu(unsigned int mask) +extern inline unsigned int any_online_cpu(unsigned int mask) { if (mask & cpu_online_map) return __ffs(mask & cpu_online_map); - return -1; + return NR_CPUS; } extern inline unsigned int num_online_cpus(void) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/