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-rw-r--r--extras/hs-test/cpu.go69
1 files changed, 69 insertions, 0 deletions
diff --git a/extras/hs-test/cpu.go b/extras/hs-test/cpu.go
new file mode 100644
index 00000000000..e17bc11fbe0
--- /dev/null
+++ b/extras/hs-test/cpu.go
@@ -0,0 +1,69 @@
+package main
+
+import (
+ "bufio"
+ "fmt"
+ "os"
+)
+
+var CPU_PATH = "/sys/fs/cgroup/cpuset.cpus.effective"
+
+type CpuContext struct {
+ cpuAllocator *CpuAllocatorT
+ cpus []int
+}
+
+func (c *CpuContext) Release() {
+ c.cpuAllocator.cpus = append(c.cpuAllocator.cpus, c.cpus...)
+ c.cpus = c.cpus[:0] // empty the list
+}
+
+type CpuAllocatorT struct {
+ cpus []int
+}
+
+var cpuAllocator *CpuAllocatorT = nil
+
+func (c *CpuAllocatorT) Allocate(nCpus int) (*CpuContext, error) {
+ var cpuCtx CpuContext
+
+ if len(c.cpus) < nCpus {
+ return nil, fmt.Errorf("could not allocate %d CPUs; available: %d", nCpus, len(c.cpus))
+ }
+ cpuCtx.cpus = c.cpus[0:nCpus]
+ cpuCtx.cpuAllocator = c
+ c.cpus = c.cpus[nCpus:]
+ return &cpuCtx, nil
+}
+
+func (c *CpuAllocatorT) readCpus(fname string) error {
+ var first, last int
+ file, err := os.Open(CPU_PATH)
+ if err != nil {
+ return err
+ }
+ defer file.Close()
+
+ sc := bufio.NewScanner(file)
+ sc.Scan()
+ line := sc.Text()
+ _, err = fmt.Sscanf(line, "%d-%d", &first, &last)
+ if err != nil {
+ return err
+ }
+ for i := first; i <= last; i++ {
+ c.cpus = append(c.cpus, i)
+ }
+ return nil
+}
+
+func CpuAllocator() (*CpuAllocatorT, error) {
+ if cpuAllocator == nil {
+ cpuAllocator = new(CpuAllocatorT)
+ err := cpuAllocator.readCpus(CPU_PATH)
+ if err != nil {
+ return nil, err
+ }
+ }
+ return cpuAllocator, nil
+}