svn commit: r214412 - in head: lib/libthr/thread sys/kern

[David Xu]

Garrett Cooper wrote:
> On Wed, Oct 27, 2010 at 2:29 AM, David Xu <davidxu at freebsd.org> wrote:
>> Author: davidxu
>> Date: Wed Oct 27 09:29:03 2010
>> New Revision: 214412
>> URL: http://svn.freebsd.org/changeset/base/214412
>>
>> Log:
>>  - Revert r214409.
>>  - Use long word to figure out sizeof kernel cpuset, hope it works.
>>
>> Modified:
>>  head/lib/libthr/thread/thr_attr.c
>>  head/sys/kern/kern_cpuset.c
>>
>> Modified: head/lib/libthr/thread/thr_attr.c
>> ==============================================================================
>> --- head/lib/libthr/thread/thr_attr.c   Wed Oct 27 07:14:46 2010        (r214411)
>> +++ head/lib/libthr/thread/thr_attr.c   Wed Oct 27 09:29:03 2010        (r214412)
>> @@ -574,13 +574,14 @@ _get_kern_cpuset_size(void)
>>
>>        if (kern_cpuset_size == 0) {
>>                size_t len;
>> +               int maxcpus;
>>
>> -               len = sizeof(kern_cpuset_size);
>> -               if (sysctlbyname("kern.smp.maxcpus", &kern_cpuset_size,
>> -                   &len, NULL, 0))
>> +               len = sizeof(maxcpus);
>> +               if (sysctlbyname("kern.smp.maxcpus", &maxcpus, &len, NULL, 0))
>>                        PANIC("failed to get sysctl kern.smp.maxcpus");
>> -
>> -               kern_cpuset_size = (kern_cpuset_size + 7) / 8;
>> +               int nbits_long = sizeof(long) * NBBY;
>> +               int num_long = (maxcpus + nbits_long - 1) / nbits_long;
>> +               kern_cpuset_size = num_long * sizeof(long);
>>        }
>>
>>        return (kern_cpuset_size);
>>
>> Modified: head/sys/kern/kern_cpuset.c
>> ==============================================================================
>> --- head/sys/kern/kern_cpuset.c Wed Oct 27 07:14:46 2010        (r214411)
>> +++ head/sys/kern/kern_cpuset.c Wed Oct 27 09:29:03 2010        (r214412)
>> @@ -889,10 +889,6 @@ cpuset_getaffinity(struct thread *td, st
>>        int error;
>>        size_t size;
>>
>> -       if (uap->cpusetsize == 0) {
>> -               td->td_retval[0] = sizeof(cpuset_t);
>> -               return (0);
>> -       }
>>        if (uap->cpusetsize < sizeof(cpuset_t) ||
>>            uap->cpusetsize > CPU_MAXSIZE / NBBY)
>>                return (ERANGE);
> 
> Are you sure this won't break 32-bit on 64-bit architectures, i.e.
> amd64, mips, powerpc64, sparc64?
> Thanks,
> -Garrett
> 
Unfortunately, I have not thought 32-bit on 64-bit kernel,
we have a bunch of system calls, but still can not get a
simple size.