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authorDaniel J Walsh <dwalsh@redhat.com>2019-01-04 10:15:38 -0500
committerDaniel J Walsh <dwalsh@redhat.com>2019-01-04 14:54:59 -0500
commit43686072d3ff559abb0aea865509ae85f8a301de (patch)
tree54946ccc3cbe4cf01355253f3d8b91194fba4a1b /pkg/sysinfo/numcpu_linux.go
parent9ffd4806163e410d51d0f0cbece45b7405ff9fee (diff)
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Update vendor of runc
Updating the vendor or runc to pull in some fixes that we need. In order to get this vendor to work, we needed to update the vendor of docker/docker, which causes all sorts of issues, just to fix the docker/pkg/sysinfo. Rather then doing this, I pulled in pkg/sysinfo into libpod and fixed the code locally. I then switched the use of docker/pkg/sysinfo to libpod/pkg/sysinfo. I also switched out the docker/pkg/mount to containers/storage/pkg/mount Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>
Diffstat (limited to 'pkg/sysinfo/numcpu_linux.go')
-rw-r--r--pkg/sysinfo/numcpu_linux.go44
1 files changed, 44 insertions, 0 deletions
diff --git a/pkg/sysinfo/numcpu_linux.go b/pkg/sysinfo/numcpu_linux.go
new file mode 100644
index 000000000..f1d2d9db3
--- /dev/null
+++ b/pkg/sysinfo/numcpu_linux.go
@@ -0,0 +1,44 @@
+// +build linux
+
+package sysinfo
+
+import (
+ "runtime"
+ "unsafe"
+
+ "golang.org/x/sys/unix"
+)
+
+// numCPU queries the system for the count of threads available
+// for use to this process.
+//
+// Issues two syscalls.
+// Returns 0 on errors. Use |runtime.NumCPU| in that case.
+func numCPU() int {
+ // Gets the affinity mask for a process: The very one invoking this function.
+ pid, _, _ := unix.RawSyscall(unix.SYS_GETPID, 0, 0, 0)
+
+ var mask [1024 / 64]uintptr
+ _, _, err := unix.RawSyscall(unix.SYS_SCHED_GETAFFINITY, pid, uintptr(len(mask)*8), uintptr(unsafe.Pointer(&mask[0])))
+ if err != 0 {
+ return 0
+ }
+
+ // For every available thread a bit is set in the mask.
+ ncpu := 0
+ for _, e := range mask {
+ if e == 0 {
+ continue
+ }
+ ncpu += int(popcnt(uint64(e)))
+ }
+ return ncpu
+}
+
+// NumCPU returns the number of CPUs which are currently online
+func NumCPU() int {
+ if ncpu := numCPU(); ncpu > 0 {
+ return ncpu
+ }
+ return runtime.NumCPU()
+}