--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/version.h>
+#include <linux/ptrace.h>
+#include <uapi/linux/bpf.h>
+#include "bpf_helpers.h"
+
+/*
+ * The CPU number, cstate number and pstate number are based
+ * on 96boards Hikey with octa CA53 CPUs.
+ *
+ * Every CPU have three idle states for cstate:
+ * WFI, CPU_OFF, CLUSTER_OFF
+ *
+ * Every CPU have 5 operating points:
+ * 208MHz, 432MHz, 729MHz, 960MHz, 1200MHz
+ *
+ * This code is based on these assumption and other platforms
+ * need to adjust these definitions.
+ */
+#define MAX_CPU 8
+#define MAX_PSTATE_ENTRIES 5
+#define MAX_CSTATE_ENTRIES 3
+
+static int cpu_opps[] = { 208000, 432000, 729000, 960000, 1200000 };
+
+/*
+ * my_map structure is used to record cstate and pstate index and
+ * timestamp (Idx, Ts), when new event incoming we need to update
+ * combination for new state index and timestamp (Idx`, Ts`).
+ *
+ * Based on (Idx, Ts) and (Idx`, Ts`) we can calculate the time
+ * interval for the previous state: Duration(Idx) = Ts` - Ts.
+ *
+ * Every CPU has one below array for recording state index and
+ * timestamp, and record for cstate and pstate saperately:
+ *
+ * +--------------------------+
+ * | cstate timestamp |
+ * +--------------------------+
+ * | cstate index |
+ * +--------------------------+
+ * | pstate timestamp |
+ * +--------------------------+
+ * | pstate index |
+ * +--------------------------+
+ */
+#define MAP_OFF_CSTATE_TIME 0
+#define MAP_OFF_CSTATE_IDX 1
+#define MAP_OFF_PSTATE_TIME 2
+#define MAP_OFF_PSTATE_IDX 3
+#define MAP_OFF_NUM 4
+
+struct bpf_map_def SEC("maps") my_map = {
+ .type = BPF_MAP_TYPE_ARRAY,
+ .key_size = sizeof(u32),
+ .value_size = sizeof(u64),
+ .max_entries = MAX_CPU * MAP_OFF_NUM,
+};
+
+/* cstate_duration records duration time for every idle state per CPU */
+struct bpf_map_def SEC("maps") cstate_duration = {
+ .type = BPF_MAP_TYPE_ARRAY,
+ .key_size = sizeof(u32),
+ .value_size = sizeof(u64),
+ .max_entries = MAX_CPU * MAX_CSTATE_ENTRIES,
+};
+
+/* pstate_duration records duration time for every operating point per CPU */
+struct bpf_map_def SEC("maps") pstate_duration = {
+ .type = BPF_MAP_TYPE_ARRAY,
+ .key_size = sizeof(u32),
+ .value_size = sizeof(u64),
+ .max_entries = MAX_CPU * MAX_PSTATE_ENTRIES,
+};
+
+/*
+ * The trace events for cpu_idle and cpu_frequency are taken from:
+ * /sys/kernel/debug/tracing/events/power/cpu_idle/format
+ * /sys/kernel/debug/tracing/events/power/cpu_frequency/format
+ *
+ * These two events have same format, so define one common structure.
+ */
+struct cpu_args {
+ u64 pad;
+ u32 state;
+ u32 cpu_id;
+};
+
+/* calculate pstate index, returns MAX_PSTATE_ENTRIES for failure */
+static u32 find_cpu_pstate_idx(u32 frequency)
+{
+ u32 i;
+
+ for (i = 0; i < sizeof(cpu_opps) / sizeof(u32); i++) {
+ if (frequency == cpu_opps[i])
+ return i;
+ }
+
+ return i;
+}
+
+SEC("tracepoint/power/cpu_idle")
+int bpf_prog1(struct cpu_args *ctx)
+{
+ u64 *cts, *pts, *cstate, *pstate, prev_state, cur_ts, delta;
+ u32 key, cpu, pstate_idx;
+ u64 *val;
+
+ if (ctx->cpu_id > MAX_CPU)
+ return 0;
+
+ cpu = ctx->cpu_id;
+
+ key = cpu * MAP_OFF_NUM + MAP_OFF_CSTATE_TIME;
+ cts = bpf_map_lookup_elem(&my_map, &key);
+ if (!cts)
+ return 0;
+
+ key = cpu * MAP_OFF_NUM + MAP_OFF_CSTATE_IDX;
+ cstate = bpf_map_lookup_elem(&my_map, &key);
+ if (!cstate)
+ return 0;
+
+ key = cpu * MAP_OFF_NUM + MAP_OFF_PSTATE_TIME;
+ pts = bpf_map_lookup_elem(&my_map, &key);
+ if (!pts)
+ return 0;
+
+ key = cpu * MAP_OFF_NUM + MAP_OFF_PSTATE_IDX;
+ pstate = bpf_map_lookup_elem(&my_map, &key);
+ if (!pstate)
+ return 0;
+
+ prev_state = *cstate;
+ *cstate = ctx->state;
+
+ if (!*cts) {
+ *cts = bpf_ktime_get_ns();
+ return 0;
+ }
+
+ cur_ts = bpf_ktime_get_ns();
+ delta = cur_ts - *cts;
+ *cts = cur_ts;
+
+ /*
+ * When state doesn't equal to (u32)-1, the cpu will enter
+ * one idle state; for this case we need to record interval
+ * for the pstate.
+ *
+ * OPP2
+ * +---------------------+
+ * OPP1 | |
+ * ---------+ |
+ * | Idle state
+ * +---------------
+ *
+ * |<- pstate duration ->|
+ * ^ ^
+ * pts cur_ts
+ */
+ if (ctx->state != (u32)-1) {
+
+ /* record pstate after have first cpu_frequency event */
+ if (!*pts)
+ return 0;
+
+ delta = cur_ts - *pts;
+
+ pstate_idx = find_cpu_pstate_idx(*pstate);
+ if (pstate_idx >= MAX_PSTATE_ENTRIES)
+ return 0;
+
+ key = cpu * MAX_PSTATE_ENTRIES + pstate_idx;
+ val = bpf_map_lookup_elem(&pstate_duration, &key);
+ if (val)
+ __sync_fetch_and_add((long *)val, delta);
+
+ /*
+ * When state equal to (u32)-1, the cpu just exits from one
+ * specific idle state; for this case we need to record
+ * interval for the pstate.
+ *
+ * OPP2
+ * -----------+
+ * | OPP1
+ * | +-----------
+ * | Idle state |
+ * +---------------------+
+ *
+ * |<- cstate duration ->|
+ * ^ ^
+ * cts cur_ts
+ */
+ } else {
+
+ key = cpu * MAX_CSTATE_ENTRIES + prev_state;
+ val = bpf_map_lookup_elem(&cstate_duration, &key);
+ if (val)
+ __sync_fetch_and_add((long *)val, delta);
+ }
+
+ /* Update timestamp for pstate as new start time */
+ if (*pts)
+ *pts = cur_ts;
+
+ return 0;
+}
+
+SEC("tracepoint/power/cpu_frequency")
+int bpf_prog2(struct cpu_args *ctx)
+{
+ u64 *pts, *cstate, *pstate, prev_state, cur_ts, delta;
+ u32 key, cpu, pstate_idx;
+ u64 *val;
+
+ cpu = ctx->cpu_id;
+
+ key = cpu * MAP_OFF_NUM + MAP_OFF_PSTATE_TIME;
+ pts = bpf_map_lookup_elem(&my_map, &key);
+ if (!pts)
+ return 0;
+
+ key = cpu * MAP_OFF_NUM + MAP_OFF_PSTATE_IDX;
+ pstate = bpf_map_lookup_elem(&my_map, &key);
+ if (!pstate)
+ return 0;
+
+ key = cpu * MAP_OFF_NUM + MAP_OFF_CSTATE_IDX;
+ cstate = bpf_map_lookup_elem(&my_map, &key);
+ if (!cstate)
+ return 0;
+
+ prev_state = *pstate;
+ *pstate = ctx->state;
+
+ if (!*pts) {
+ *pts = bpf_ktime_get_ns();
+ return 0;
+ }
+
+ cur_ts = bpf_ktime_get_ns();
+ delta = cur_ts - *pts;
+ *pts = cur_ts;
+
+ /* When CPU is in idle, bail out to skip pstate statistics */
+ if (*cstate != (u32)(-1))
+ return 0;
+
+ /*
+ * The cpu changes to another different OPP (in below diagram
+ * change frequency from OPP3 to OPP1), need recording interval
+ * for previous frequency OPP3 and update timestamp as start
+ * time for new frequency OPP1.
+ *
+ * OPP3
+ * +---------------------+
+ * OPP2 | |
+ * ---------+ |
+ * | OPP1
+ * +---------------
+ *
+ * |<- pstate duration ->|
+ * ^ ^
+ * pts cur_ts
+ */
+ pstate_idx = find_cpu_pstate_idx(*pstate);
+ if (pstate_idx >= MAX_PSTATE_ENTRIES)
+ return 0;
+
+ key = cpu * MAX_PSTATE_ENTRIES + pstate_idx;
+ val = bpf_map_lookup_elem(&pstate_duration, &key);
+ if (val)
+ __sync_fetch_and_add((long *)val, delta);
+
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
+u32 _version SEC("version") = LINUX_VERSION_CODE;
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <sched.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <linux/bpf.h>
+#include <locale.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <sys/wait.h>
+
+#include "libbpf.h"
+#include "bpf_load.h"
+
+#define MAX_CPU 8
+#define MAX_PSTATE_ENTRIES 5
+#define MAX_CSTATE_ENTRIES 3
+#define MAX_STARS 40
+
+#define CPUFREQ_MAX_SYSFS_PATH "/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq"
+#define CPUFREQ_LOWEST_FREQ "208000"
+#define CPUFREQ_HIGHEST_FREQ "12000000"
+
+struct cpu_stat_data {
+ unsigned long cstate[MAX_CSTATE_ENTRIES];
+ unsigned long pstate[MAX_PSTATE_ENTRIES];
+};
+
+static struct cpu_stat_data stat_data[MAX_CPU];
+
+static void cpu_stat_print(void)
+{
+ int i, j;
+ char state_str[sizeof("cstate-9")];
+ struct cpu_stat_data *data;
+
+ /* Clear screen */
+ printf("\033[2J");
+
+ /* Header */
+ printf("\nCPU states statistics:\n");
+ printf("%-10s ", "state(ms)");
+
+ for (i = 0; i < MAX_CSTATE_ENTRIES; i++) {
+ sprintf(state_str, "cstate-%d", i);
+ printf("%-11s ", state_str);
+ }
+
+ for (i = 0; i < MAX_PSTATE_ENTRIES; i++) {
+ sprintf(state_str, "pstate-%d", i);
+ printf("%-11s ", state_str);
+ }
+
+ printf("\n");
+
+ for (j = 0; j < MAX_CPU; j++) {
+ data = &stat_data[j];
+
+ printf("CPU-%-6d ", j);
+ for (i = 0; i < MAX_CSTATE_ENTRIES; i++)
+ printf("%-11ld ", data->cstate[i] / 1000000);
+
+ for (i = 0; i < MAX_PSTATE_ENTRIES; i++)
+ printf("%-11ld ", data->pstate[i] / 1000000);
+
+ printf("\n");
+ }
+}
+
+static void cpu_stat_update(int cstate_fd, int pstate_fd)
+{
+ unsigned long key, value;
+ int c, i;
+
+ for (c = 0; c < MAX_CPU; c++) {
+ for (i = 0; i < MAX_CSTATE_ENTRIES; i++) {
+ key = c * MAX_CSTATE_ENTRIES + i;
+ bpf_map_lookup_elem(cstate_fd, &key, &value);
+ stat_data[c].cstate[i] = value;
+ }
+
+ for (i = 0; i < MAX_PSTATE_ENTRIES; i++) {
+ key = c * MAX_PSTATE_ENTRIES + i;
+ bpf_map_lookup_elem(pstate_fd, &key, &value);
+ stat_data[c].pstate[i] = value;
+ }
+ }
+}
+
+/*
+ * This function is copied from 'idlestat' tool function
+ * idlestat_wake_all() in idlestate.c.
+ *
+ * It sets the self running task affinity to cpus one by one so can wake up
+ * the specific CPU to handle scheduling; this results in all cpus can be
+ * waken up once and produce ftrace event 'trace_cpu_idle'.
+ */
+static int cpu_stat_inject_cpu_idle_event(void)
+{
+ int rcpu, i, ret;
+ cpu_set_t cpumask;
+ cpu_set_t original_cpumask;
+
+ ret = sysconf(_SC_NPROCESSORS_CONF);
+ if (ret < 0)
+ return -1;
+
+ rcpu = sched_getcpu();
+ if (rcpu < 0)
+ return -1;
+
+ /* Keep track of the CPUs we will run on */
+ sched_getaffinity(0, sizeof(original_cpumask), &original_cpumask);
+
+ for (i = 0; i < ret; i++) {
+
+ /* Pointless to wake up ourself */
+ if (i == rcpu)
+ continue;
+
+ /* Pointless to wake CPUs we will not run on */
+ if (!CPU_ISSET(i, &original_cpumask))
+ continue;
+
+ CPU_ZERO(&cpumask);
+ CPU_SET(i, &cpumask);
+
+ sched_setaffinity(0, sizeof(cpumask), &cpumask);
+ }
+
+ /* Enable all the CPUs of the original mask */
+ sched_setaffinity(0, sizeof(original_cpumask), &original_cpumask);
+ return 0;
+}
+
+/*
+ * It's possible to have no any frequency change for long time and cannot
+ * get ftrace event 'trace_cpu_frequency' for long period, this introduces
+ * big deviation for pstate statistics.
+ *
+ * To solve this issue, below code forces to set 'scaling_max_freq' to 208MHz
+ * for triggering ftrace event 'trace_cpu_frequency' and then recovery back to
+ * the maximum frequency value 1.2GHz.
+ */
+static int cpu_stat_inject_cpu_frequency_event(void)
+{
+ int len, fd;
+
+ fd = open(CPUFREQ_MAX_SYSFS_PATH, O_WRONLY);
+ if (fd < 0) {
+ printf("failed to open scaling_max_freq, errno=%d\n", errno);
+ return fd;
+ }
+
+ len = write(fd, CPUFREQ_LOWEST_FREQ, strlen(CPUFREQ_LOWEST_FREQ));
+ if (len < 0) {
+ printf("failed to open scaling_max_freq, errno=%d\n", errno);
+ goto err;
+ }
+
+ len = write(fd, CPUFREQ_HIGHEST_FREQ, strlen(CPUFREQ_HIGHEST_FREQ));
+ if (len < 0) {
+ printf("failed to open scaling_max_freq, errno=%d\n", errno);
+ goto err;
+ }
+
+err:
+ close(fd);
+ return len;
+}
+
+static void int_exit(int sig)
+{
+ cpu_stat_inject_cpu_idle_event();
+ cpu_stat_inject_cpu_frequency_event();
+ cpu_stat_update(map_fd[1], map_fd[2]);
+ cpu_stat_print();
+ exit(0);
+}
+
+int main(int argc, char **argv)
+{
+ char filename[256];
+ int ret;
+
+ snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+ if (load_bpf_file(filename)) {
+ printf("%s", bpf_log_buf);
+ return 1;
+ }
+
+ ret = cpu_stat_inject_cpu_idle_event();
+ if (ret < 0)
+ return 1;
+
+ ret = cpu_stat_inject_cpu_frequency_event();
+ if (ret < 0)
+ return 1;
+
+ signal(SIGINT, int_exit);
+ signal(SIGTERM, int_exit);
+
+ while (1) {
+ cpu_stat_update(map_fd[1], map_fd[2]);
+ cpu_stat_print();
+ sleep(5);
+ }
+
+ return 0;
+}
projects / mirror_ubuntu-disco-kernel.git / commitdiff