diff options
Diffstat (limited to 'target/i386/kvm/vmsr_energy.c')
| -rw-r--r-- | target/i386/kvm/vmsr_energy.c | 344 |
1 files changed, 344 insertions, 0 deletions
diff --git a/target/i386/kvm/vmsr_energy.c b/target/i386/kvm/vmsr_energy.c new file mode 100644 index 0000000..d6aad52 --- /dev/null +++ b/target/i386/kvm/vmsr_energy.c @@ -0,0 +1,344 @@ +/* + * QEMU KVM support -- x86 virtual RAPL msr + * + * Copyright 2024 Red Hat, Inc. 2024 + * + * Author: + * Anthony Harivel <aharivel@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include "qemu/osdep.h" +#include "qemu/error-report.h" +#include "vmsr_energy.h" +#include "io/channel.h" +#include "io/channel-socket.h" +#include "hw/boards.h" +#include "cpu.h" +#include "host-cpu.h" + +char *vmsr_compute_default_paths(void) +{ + g_autofree char *state = qemu_get_local_state_dir(); + + return g_build_filename(state, "run", "qemu-vmsr-helper.sock", NULL); +} + +bool is_host_cpu_intel(void) +{ + char vendor[CPUID_VENDOR_SZ + 1]; + + host_cpu_vendor_fms(vendor, NULL, NULL, NULL); + + return g_str_equal(vendor, CPUID_VENDOR_INTEL); +} + +int is_rapl_enabled(void) +{ + const char *path = "/sys/class/powercap/intel-rapl/enabled"; + FILE *file = fopen(path, "r"); + int value = 0; + + if (file != NULL) { + if (fscanf(file, "%d", &value) != 1) { + error_report("INTEL RAPL not enabled"); + } + fclose(file); + } else { + error_report("Error opening %s", path); + } + + return value; +} + +QIOChannelSocket *vmsr_open_socket(const char *path) +{ + g_autofree char *socket_path = NULL; + + socket_path = g_strdup(path); + + SocketAddress saddr = { + .type = SOCKET_ADDRESS_TYPE_UNIX, + .u.q_unix.path = socket_path + }; + + QIOChannelSocket *sioc = qio_channel_socket_new(); + Error *local_err = NULL; + + qio_channel_set_name(QIO_CHANNEL(sioc), "vmsr-helper"); + qio_channel_socket_connect_sync(sioc, + &saddr, + &local_err); + if (local_err) { + /* Close socket. */ + qio_channel_close(QIO_CHANNEL(sioc), NULL); + object_unref(OBJECT(sioc)); + sioc = NULL; + goto out; + } + + qio_channel_set_delay(QIO_CHANNEL(sioc), false); +out: + return sioc; +} + +uint64_t vmsr_read_msr(uint32_t reg, uint32_t cpu_id, uint32_t tid, + QIOChannelSocket *sioc) +{ + uint64_t data = 0; + int r = 0; + Error *local_err = NULL; + uint32_t buffer[3]; + /* + * Send the required arguments: + * 1. RAPL MSR register to read + * 2. On which CPU ID + * 3. From which vCPU (Thread ID) + */ + buffer[0] = reg; + buffer[1] = cpu_id; + buffer[2] = tid; + + r = qio_channel_write_all(QIO_CHANNEL(sioc), + (char *)buffer, sizeof(buffer), + &local_err); + if (r < 0) { + goto out_close; + } + + r = qio_channel_read(QIO_CHANNEL(sioc), + (char *)&data, sizeof(data), + &local_err); + if (r < 0) { + data = 0; + goto out_close; + } + +out_close: + return data; +} + +/* Retrieve the max number of physical package */ +unsigned int vmsr_get_max_physical_package(unsigned int max_cpus) +{ + const char *dir = "/sys/devices/system/cpu/"; + const char *topo_path = "topology/physical_package_id"; + g_autofree int *uniquePackages = g_new0(int, max_cpus); + unsigned int packageCount = 0; + FILE *file = NULL; + + for (int i = 0; i < max_cpus; i++) { + g_autofree char *filePath = NULL; + g_autofree char *cpuid = g_strdup_printf("cpu%d", i); + + filePath = g_build_filename(dir, cpuid, topo_path, NULL); + + file = fopen(filePath, "r"); + + if (file == NULL) { + error_report("Error opening physical_package_id file"); + return 0; + } + + char packageId[10]; + if (fgets(packageId, sizeof(packageId), file) == NULL) { + packageCount = 0; + } + + fclose(file); + + int currentPackageId = atoi(packageId); + + bool isUnique = true; + for (int j = 0; j < packageCount; j++) { + if (uniquePackages[j] == currentPackageId) { + isUnique = false; + break; + } + } + + if (isUnique) { + uniquePackages[packageCount] = currentPackageId; + packageCount++; + + if (packageCount >= max_cpus) { + break; + } + } + } + + return (packageCount == 0) ? 1 : packageCount; +} + +/* Retrieve the max number of physical cpu on the host */ +unsigned int vmsr_get_maxcpus(void) +{ + GDir *dir; + const gchar *entry_name; + unsigned int cpu_count = 0; + const char *path = "/sys/devices/system/cpu/"; + + dir = g_dir_open(path, 0, NULL); + if (dir == NULL) { + error_report("Unable to open cpu directory"); + return -1; + } + + while ((entry_name = g_dir_read_name(dir)) != NULL) { + if (g_ascii_strncasecmp(entry_name, "cpu", 3) == 0 && + isdigit(entry_name[3])) { + cpu_count++; + } + } + + g_dir_close(dir); + + return cpu_count; +} + +/* Count the number of physical cpu on each packages */ +unsigned int vmsr_count_cpus_per_package(unsigned int *package_count, + unsigned int max_pkgs) +{ + g_autofree char *file_contents = NULL; + g_autofree char *path = NULL; + g_autofree char *path_name = NULL; + gsize length; + + /* Iterate over cpus and count cpus in each package */ + for (int cpu_id = 0; ; cpu_id++) { + path_name = g_strdup_printf("/sys/devices/system/cpu/cpu%d/" + "topology/physical_package_id", cpu_id); + + path = g_build_filename(path_name, NULL); + + if (!g_file_get_contents(path, &file_contents, &length, NULL)) { + break; /* No more cpus */ + } + + /* Get the physical package ID for this CPU */ + int package_id = atoi(file_contents); + + /* Check if the package ID is within the known number of packages */ + if (package_id >= 0 && package_id < max_pkgs) { + /* If yes, count the cpu for this package*/ + package_count[package_id]++; + } + } + + return 0; +} + +/* Get the physical package id from a given cpu id */ +int vmsr_get_physical_package_id(int cpu_id) +{ + g_autofree char *file_contents = NULL; + g_autofree char *file_path = NULL; + int package_id = -1; + gsize length; + + file_path = g_strdup_printf("/sys/devices/system/cpu/cpu%d" + "/topology/physical_package_id", cpu_id); + + if (!g_file_get_contents(file_path, &file_contents, &length, NULL)) { + goto out; + } + + package_id = atoi(file_contents); + +out: + return package_id; +} + +/* Read the scheduled time for a given thread of a give pid */ +void vmsr_read_thread_stat(pid_t pid, + unsigned int thread_id, + unsigned long long *utime, + unsigned long long *stime, + unsigned int *cpu_id) +{ + g_autofree char *path = NULL; + g_autofree char *path_name = NULL; + + path_name = g_strdup_printf("/proc/%u/task/%d/stat", pid, thread_id); + + path = g_build_filename(path_name, NULL); + + FILE *file = fopen(path, "r"); + if (file == NULL) { + error_report("Error opening %s", path_name); + return; + } + + if (fscanf(file, "%*d (%*[^)]) %*c %*d %*d %*d %*d %*d %*u %*u %*u %*u %*u" + " %llu %llu %*d %*d %*d %*d %*d %*d %*u %*u %*d %*u %*u" + " %*u %*u %*u %*u %*u %*u %*u %*u %*u %*d %*u %*u %u", + utime, stime, cpu_id) != 3) + { + fclose(file); + error_report("Error fscanf did not report the right amount of items"); + return; + } + + fclose(file); +} + +/* Read QEMU stat task folder to retrieve all QEMU threads ID */ +pid_t *vmsr_get_thread_ids(pid_t pid, unsigned int *num_threads) +{ + g_autofree char *task_path = g_strdup_printf("%d/task", pid); + g_autofree char *path = g_build_filename("/proc", task_path, NULL); + + DIR *dir = opendir(path); + if (dir == NULL) { + error_report("Error opening /proc/qemu/task"); + return NULL; + } + + pid_t *thread_ids = NULL; + unsigned int thread_count = 0; + + g_autofree struct dirent *ent = NULL; + while ((ent = readdir(dir)) != NULL) { + if (ent->d_name[0] == '.') { + continue; + } + pid_t tid = atoi(ent->d_name); + if (pid != tid) { + thread_ids = g_renew(pid_t, thread_ids, (thread_count + 1)); + thread_ids[thread_count] = tid; + thread_count++; + } + } + + closedir(dir); + + *num_threads = thread_count; + return thread_ids; +} + +void vmsr_delta_ticks(vmsr_thread_stat *thd_stat, int i) +{ + thd_stat[i].delta_ticks = (thd_stat[i].utime[1] + thd_stat[i].stime[1]) + - (thd_stat[i].utime[0] + thd_stat[i].stime[0]); +} + +double vmsr_get_ratio(uint64_t e_delta, + unsigned long long delta_ticks, + unsigned int maxticks) +{ + return (e_delta / 100.0) * ((100.0 / maxticks) * delta_ticks); +} + +void vmsr_init_topo_info(X86CPUTopoInfo *topo_info, + const MachineState *ms) +{ + topo_info->dies_per_pkg = ms->smp.dies; + topo_info->modules_per_die = ms->smp.modules; + topo_info->cores_per_module = ms->smp.cores; + topo_info->threads_per_core = ms->smp.threads; +} + |