Add performance tracing for virtual machines

Author: m8

src/hypervisor/kvm/perf.hpp

@@ -0,0 +1,88 @@
+#pragma once
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <linux/perf_event.h>
+#include <asm/unistd.h>
+#include <sys/mman.h>
+#include <vector>
+#include <cstdio>
+
+__u32 buf_size_shift = 8;
+__u32 PERF_FD = 0;
+
+static long perf_event_open(perf_event_attr *hw_event, pid_t pid, int cpu, int group_fd, unsigned long flags)
+{
+    int ret;
+    ret = syscall(__NR_perf_event_open, hw_event, pid, cpu,
+                  group_fd, flags);
+    return ret;
+}
+
+static unsigned perf_mmap_size(int buf_size_shift)
+{
+    return ((1U << buf_size_shift) + 1) * sysconf(_SC_PAGESIZE);
+}
+
+
+int mumu_perf_init()
+{
+    struct perf_event_attr pe;
+    long long count;
+    int fd;
+
+    memset(&pe, 0, sizeof(pe));
+    pe.type = PERF_TYPE_HW_CACHE;
+    pe.size = sizeof(pe);
+    pe.config = (PERF_COUNT_HW_CACHE_LL) | (PERF_COUNT_HW_CACHE_OP_READ << 8) | (PERF_COUNT_HW_CACHE_RESULT_MISS << 16);
+
+    pe.exclude_host = 1;   
+    pe.exclude_hv = 0; 
+    
+    fd = perf_event_open(&pe, 0, -1, -1,0);
+    if (fd == -1)
+    {
+        fprintf(stderr, "Error opening leader %llx\n", pe.config);
+        exit(EXIT_FAILURE);
+    }
+
+    struct perf_event_mmap_page *mpage;
+    mpage = (perf_event_mmap_page *) mmap(NULL,  perf_mmap_size(buf_size_shift), PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+    
+    if (mpage == (struct perf_event_mmap_page *)-1L) {
+        close(fd);
+        exit(EXIT_FAILURE);
+    }
+
+    PERF_FD = fd;
+    return PERF_FD;
+}
+
+
+void mumu_perf_reset_counters()
+{
+    ioctl(PERF_FD, PERF_EVENT_IOC_RESET, 0);
+    return;
+}
+
+void mumu_perf_start_counters()
+{
+    ioctl(PERF_FD, PERF_EVENT_IOC_ENABLE, 0);
+    return;
+}
+
+void mumu_perf_stop_counters()
+{
+    ioctl(PERF_FD, PERF_EVENT_IOC_DISABLE, 0);
+    return;
+}
+
+long long mumu_perf_read_counters()
+{
+    long long count;
+    read(PERF_FD, &count, sizeof(count));
+    return count;
+}