wireguard-openbsd/lib/libc/gen/sysconf.c, branch jd/queueboosts

Add hw.ncpuonline to count the number of online CPUs.

2018-07-12T01:23:38Z

The introduction of hw.smt means that logical CPUs can be disabled after boot and prior to suspend/resume. If hw.smt=0 (the default), there needs to be a way to count the number of hardware threads available on the system at any given time. So, import HW_NCPUONLINE/hw.ncpuonline from NetBSD and document it. hw.ncpu becomes equal to the number of CPUs given to sched_init_cpu() during boot, while hw.ncpuonline is equal to the number of CPUs available to the scheduler in the cpuset "sched_all_cpus". Set_SC_NPROCESSORS_ONLN equal to this new sysctl and keep _SC_NPROCESSORS_CONF equal to hw.ncpu. This is preferable to adding a new sysctl to count the number of configured CPUs and keeping hw.ncpu equal to the number of online CPUs because such a change would break software in the ecosystem that relies on HW_NCPU/hw.ncpu to measure CPU usage and the like. Such software in base includes top(1), systat(1), and snmpd(8), and perhaps others. We don't need additional locking to count the cardinality of a cpuset in this case because the only interfaces that can modify said cardinality are sysctl(2) and ioctl(2), both of which are under the KERNEL_LOCK. Software using HW_NCPU/hw.ncpu to determine optimal parallism will need to be updated to use HW_NCPUONLINE/hw.ncpuonline. Until then, such software may perform suboptimally. However, most changes will be similar to the change included here for libcxx's std::thread:hardware_concurrency(): using HW_NCPUONLINE in lieu of HW_NCPU should be sufficient for determining optimal parallelism for most software if the change to _SC_NPROCESSORS_ONLN is insufficient. Prompted by deraadt. Discussed at length with kettenis, deraadt, and sthen. Lots of patch tweaks from kettenis. ok kettenis, "proceed" deraadt

shm_open(), sysconf(), tcflow(), and tcsendbreak() are not permitted to be

2017-09-10T18:20:00Z

cancellation points in POSIX, so change them to invoke the non-cancellation point versions of open(), close(), nanosleep(), and write() ok deraadt@ millert@

Rearrange C runtime bits: now that ld.so exports environ and __progname,

2016-03-20T02:32:39Z

move their definitions and initialization in static links to libc.a Make crt0 always invoke a new func _csu_finish() in libc to process the auxv and to either register the ld.so cleanup function (in dynamic links) or initialize environ and __progname and do MC_DISABLE_KBIND (in static links). In libc, get pagesize from auxv; cache that between getpagesize() and sysconf(_SC_PAGESIZE) ok mpi@ "good time" deraadt@

Wrap so that internal calls go direct and they're all weak symbols

2015-09-12T14:56:50Z

Delete unused 'fd' argument from internal function oldttyname()

Replace HOST_NAME_MAX+1-1 with HOST_NAME_MAX. OK deraad@

2015-01-16T18:18:58Z

Move to the universe.

2015-01-16T16:48:51Z

review by millert, binary checking process with doug, concept with guenther

decouple struct uvmexp into a new file, so that uvm_extern.h and sysctl.h

2014-07-08T17:19:21Z

don't need to be married. ok guenther miod beck jsing kettenis

Use VM_UVMEXP instead of VM_METER for memory usages and directly

2014-04-08T14:04:11Z

include where it is needed instead of relying on it being included by . miod@ likes it, ok guenther@

sysconf(_SC_SEM_VALUE_MAX) should return SEM_VALUE_MAX, not some

2013-03-24T20:04:35Z

unrelated sysv sem limit. Similarly, sysconf(_SC_SEM_NSEMS_MAX) should return -1 instead of another sysv sem limit.

Fix _SC_CHILD_MAX, _SC_OPEN_MAX, and _SC_STREAM_MAX to correctly

2012-08-29T21:46:29Z

handle rlim_cur set to RLIM_INFINITY or values greater than LONG_MAX, as unlikely as those are to happen. Further limit _SC_STREAM_MAX to at most SHRT_MAX, because struct __sFILE uses a short int for storing the file descriptor. While here, also remove a dead label that Clang complains about. From FreeBSD via Brad.