<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW --- - cairo-perf does not deal with cpus larger then 1024 well." href="https://bugs.freedesktop.org/show_bug.cgi?id=66783#c2">Comment # 2</a> on <a class="bz_bug_link bz_status_NEW " title="NEW --- - cairo-perf does not deal with cpus larger then 1024 well." href="https://bugs.freedesktop.org/show_bug.cgi?id=66783">bug 66783</a> from <a class="email" href="mailto:nzimmer@sgi.com" title="Nathan Zimmer <nzimmer@sgi.com>"> Nathan Zimmer</a> <pre>Ah, you are correct I was misreading the code. >If CPU_SETSIZE doesn't match the value as used by the kernel, sched_getaffinity() is meant >to return -EINVAL. Is that the case on your system? They don't need to match but the user does need to provide enough space for the bitmask. So it works fine on systems where CPU_SETSIZE is greater then or equal to the number of configured cpus. I don't think ignoring a error status is wise. If you don't think the check is needed that would be fine by me. But if someone is insistent here are the two standard ways I found: #ifdef _SC_NPROCESSORS_CONF int nrcpus = sysconf(_SC_NPROCESSORS_CONF); cpu_set_t * cpu_mask; cpu_mask = CPU_ALLOC(nrcpus); mask_size = CPU_ALLOC_SIZE(nrcpus); sched_getaffinity(0, mask_size, &cpu_mask); cpu_count = CPU_COUNT_S(mask_size, cpu_mask); CPU_FREE(cpu_mask); #endif or if someone has and aversion to _SC_NPROCESSORS_CONF int nrcpus = 1024; realloc: cpus = CPU_ALLOC(nrcpus); size = CPU_ALLOC_SIZE(nrcpus); CPU_ZERO_S(size, cpus); if (sched_getaffinity(0, size, cpus)) { if( errno == EINVAL && nrcpus < (4096<<4) ) { CPU_FREE(cpus); nrcpus <= 1; goto realloc; } fatal("sched_getaffinity", ERR_SYSCALL, "Can't get CPU info\n"); } cpu_count = CPU_COUNT_S(size, cpus); CPU_FREE(cpus);</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>