<!doctype html public "-//w3c//dtd html 4.0 transitional//en"> <html> Haren Myneni wrote: <blockquote TYPE=CITE> <tt>crash-utility-bounces@redhat.com wrote on 03/09/2006 12:24:26 PM:</tt> <tt>> Dave Anderson wrote:</tt> <tt>></tt> <tt>> > Sorry -- I see that NR_CPUS is 128 for ppc64 in crash...</tt> <tt>> ></tt> <tt>> > But the question remains, do you want to absolutely depend</tt> <tt>> > upon that always being the case in the kernel?</tt> <tt>> ></tt> <tt>> > Dave</tt> <tt>></tt> <tt>> Actually, looking again at the paca code, it doesn't seem that</tt> <tt>> it is dependent upon the kernel NR_CPUS value.</tt> <tt>Dave,</tt> <tt>Since, we are iterating on nr_paca, though that it may not be an issue even if the kernel changed NR_CPUS to < 128. The only issue is we are reading NR_CPUS/8 for cpu_online_map - not using the remaining part.</tt> <tt>Probably, it will be more clear if you the cpu_online_map size is based on nr_paca.</tt> <tt>Like moving the following line after calculated nr_paca:</tt> + readmem(symbol_value("cpu_online_map"), KVADDR, &cpu_online_map[0], + nr_paca/8, "cpu_online_map", FAULT_ON_ERROR); + <tt>Can I go ahead and change it? - drawback of this approach is if the NR_CPUS in the kernel is greater than 128.</tt> </blockquote> <tt>Well, if NR_CPUS goes above 128 in the kernel, then</tt> <tt>crash will fail in kernel_init() with:</tt> <tt> </tt> <tt> if (kt->cpus > NR_CPUS) {</tt> <tt> error(WARNING,</tt> <tt> "calculated number of cpus (%d) greater than compiled-in NR_CPUS (%d)\n",</tt> <tt> kt->cpus, NR_CPUS);</tt> <tt> error(FATAL, "recompile crash with larger NR_CPUS\n");</tt> <tt> }</tt><tt></tt> <tt>so that's not really a problem.</tt> <blockquote TYPE=CITE> <tt>or do you prefer actual allocating the online_map based on nr_paca? I will make changes based on your suggestions.</tt> </blockquote> <tt>I don't care either way -- I just want you guys to be happy. ;-)</tt><tt></tt> <tt>So just tell me how you want it, i.e., either keep the patch as is,</tt> <tt>or send an updated one.</tt><tt></tt> <tt>Dave</tt> <tt></tt> </html>