Initialize struct cpufreq_pstates with initial P-state of CPUs and allocate struct cpufreq_pstate dynamically when parsing trace file to solve the issue caused by missing "scaling_avaialable_freqs" attr when using intel_pstate driver.
Changes v2 to v3: Initialize struct cpufreq_pstates with initial P-state of all CPUs and beginning timestamp before trace acquisition and close all P-states with ending timestamp
hanges v1 to v2: Sort the cpufreq_pstate list when parsing events
Signed-off-by: Pi-Cheng Chen pi-cheng.chen@linaro.org --- idlestat.c | 259 ++++++++++++++++++++++++++++++++++++++++++++----------------- idlestat.h | 7 ++ trace.h | 1 + 3 files changed, 195 insertions(+), 72 deletions(-)
diff --git a/idlestat.c b/idlestat.c index da615cb..8230067 100644 --- a/idlestat.c +++ b/idlestat.c @@ -536,6 +536,121 @@ static struct cpuidle_cstates *build_cstate_info(int nrcpus) return cstates; }
+#define TRACE_STAT_FORMAT "%*[^:]:%lf" + +static double get_trace_ts(void) +{ + FILE *f; + double ts; + + f = fopen(TRACE_STAT_FILE, "r"); + if (!f) + return -1; + + while (fgets(buffer, BUFSIZE, f)) { + if (!strstr(buffer, "now ts")) + continue; + if (!sscanf(buffer, TRACE_STAT_FORMAT, &ts)) + ts = -1; + break; + } + fclose(f); + + return ts; +} + +static void release_init_pstates(struct init_pstates *init) +{ + free(init->freqs); + free(init); +} + +static struct init_pstates *build_init_pstates(void) +{ + struct init_pstates *init; + int nr_cpus, cpu; + unsigned int *freqs; + + nr_cpus = sysconf(_SC_NPROCESSORS_CONF); + if (nr_cpus < 0) + return NULL; + + init = malloc(sizeof(*init)); + if (!init) + return NULL; + + freqs = calloc(nr_cpus, sizeof(*freqs)); + if (!freqs) { + free(init); + return NULL; + } + memset(freqs, 0, sizeof(*freqs) * nr_cpus); + + for (cpu = 0; cpu < nr_cpus; cpu++) { + char *fpath; + unsigned int *freq = &(freqs[cpu]); + + if (asprintf(&fpath, CPUFREQ_CURFREQ_PATH_FORMAT, cpu) < 0) { + release_init_pstates(init); + return NULL; + } + if (read_int(fpath, (int *)freq)) + *freq = 0; + free(fpath); + } + init->nr_cpus = nr_cpus; + init->freqs = freqs; + + return init; +} + +/** + * alloc_pstate - allocate, sort, and initialize pstate struct + * to maintain statistics of P-state transitions + * @pstates: per-CPU P-state statistics struct + * @freq: frequency for which the newly pstate is allocated + * + * Return: the index of the newly allocated pstate struct + */ +static int alloc_pstate(struct cpufreq_pstates *pstates, unsigned int freq) +{ + struct cpufreq_pstate *pstate, *tmp; + int nrfreq, i, next = 0; + + pstate = pstates->pstate; + nrfreq = pstates->max; + + tmp = realloc(pstate, sizeof(*pstate) * (nrfreq + 1)); + if (!tmp) { + perror("realloc pstate"); + return -1; + } + pstate = tmp; + pstates->pstate = tmp; + pstates->max = nrfreq + 1; + + for (i = 0; i < nrfreq && freq <= pstate[i].freq; i++) + ; + + next = i; + for (i = nrfreq; i > next && i > 0; i--) { + pstate[i] = pstate[i - 1]; + pstate[i].id = i; + pstates->current = (pstates->current == i - 1)? + i : pstates->current; + } + + pstate[next].id = next; + pstate[next].freq = freq; + pstate[next].count = 0; + pstate[next].min_time = DBL_MAX; + pstate[next].max_time = 0; + pstate[next].avg_time = 0; + pstate[next].duration = 0; + + return next; +} + /** * release_pstate_info - free all P-state related structs * @pstates: per-cpu array of P-state statistics structs @@ -560,14 +675,16 @@ static void release_pstate_info(struct cpufreq_pstates *pstates, int nrcpus) return; }
-/** - * build_pstate_info - parse cpufreq sysfs entries and build per-CPU - * structs to maintain statistics of P-state transitions +/* build_pstate_info - allocate and initialize per-CPU structs to + * maintain statistics of P-state transitions * @nrcpus: number of CPUs + * @initp: initial P-state of CPUs before trace acquistion + * @start_ts: timestamp when trace acquisition started * * Return: per-CPU array of structs (success) or NULL (error) */ -static struct cpufreq_pstates *build_pstate_info(int nrcpus) +static struct cpufreq_pstates *build_pstate_info(int nrcpus, + struct init_pstates *initp, double start_ts) { int cpu; struct cpufreq_pstates *pstates; @@ -577,67 +694,28 @@ static struct cpufreq_pstates *build_pstate_info(int nrcpus) return NULL; memset(pstates, 0, sizeof(*pstates) * nrcpus);
- for (cpu = 0; cpu < nrcpus; cpu++) { - struct cpufreq_pstate *pstate; - int nrfreq; - char *fpath, *freq, line[256]; - FILE *sc_av_freq; - - if (asprintf(&fpath, CPUFREQ_AVFREQ_PATH_FORMAT, cpu) < 0) - goto clean_exit; - - /* read scaling_available_frequencies for the CPU */ - sc_av_freq = fopen(fpath, "r"); - free(fpath); - if (!sc_av_freq) { - fprintf(stderr, "warning: P-states not supported for " - "CPU%d\n", cpu); - continue; - } - freq = fgets(line, sizeof(line)/sizeof(line[0]), sc_av_freq); - fclose(sc_av_freq); - if (!freq) { - /* unlikely to be here, but just in case... */ - fprintf(stderr, "warning: P-state info not found for " - "CPU%d\n", cpu); - continue; - } + if (initp) + assert(initp->nr_cpus == nrcpus);
- /* tokenize line and populate each frequency */ - nrfreq = 0; - pstate = NULL; - while ((freq = strtok(freq, "\n ")) != NULL) { - struct cpufreq_pstate *tmp = realloc(pstate, sizeof(*pstate) * (nrfreq+1)); - if (!tmp) - goto clean_exit; - pstate = tmp; - - /* initialize pstate record */ - pstate[nrfreq].id = nrfreq; - pstate[nrfreq].freq = atol(freq); - pstate[nrfreq].count = 0; - pstate[nrfreq].min_time = DBL_MAX; - pstate[nrfreq].max_time = 0.; - pstate[nrfreq].avg_time = 0.; - pstate[nrfreq].duration = 0.; - nrfreq++; - freq = NULL; + for (cpu = 0; cpu < nrcpus; cpu++) { + struct cpufreq_pstates *ps = &(pstates[cpu]); + + ps->pstate = NULL; + ps->max = 0; + ps->current = -1; /* unknown */ + ps->idle = -1; /* unknown */ + ps->time_enter = 0.; + ps->time_exit = 0.; + + if (initp && initp->freqs[cpu] > 0 && start_ts > 0) { + ps->current = alloc_pstate(ps, initp->freqs[cpu]); + assert(ps->current >= 0); + ps->time_enter = start_ts; + ps->idle = 0; } - - /* now populate cpufreq_pstates for this CPU */ - pstates[cpu].pstate = pstate; - pstates[cpu].max = nrfreq; - pstates[cpu].current = -1; /* unknown */ - pstates[cpu].idle = -1; /* unknown */ - pstates[cpu].time_enter = 0.; - pstates[cpu].time_exit = 0.; }
return pstates; - -clean_exit: - release_pstate_info(pstates, nrcpus); - return NULL; }
static int get_current_pstate(struct cpuidle_datas *datas, int cpu, @@ -712,6 +790,9 @@ static void cpu_change_pstate(struct cpuidle_datas *datas, int cpu,
cur = get_current_pstate(datas, cpu, &ps, &p); next = freq_to_pstate_index(ps, freq); + if (next < 0) + next = alloc_pstate(ps, freq); + assert(next >= 0);
switch (cur) { case 1: @@ -742,6 +823,19 @@ static void cpu_change_pstate(struct cpuidle_datas *datas, int cpu, } }
+static void cpu_close_all_pstate(struct cpuidle_datas *datas, double time) +{ + struct cpufreq_pstates *ps; + struct cpufreq_pstate *p; + int cpu, cur; + + for (cpu = 0; cpu < datas->nrcpus; cpu++) { + cur = get_current_pstate(datas, cpu, &ps, &p); + if (p && !cur && time > 0) + close_current_pstate(ps, time); + } +} + static void cpu_pstate_idle(struct cpuidle_datas *datas, int cpu, double time) { struct cpufreq_pstates *ps = &(datas->pstates[cpu]); @@ -763,7 +857,6 @@ static int store_data(double time, int state, int cpu, struct cpuidle_datas *datas, int count) { struct cpuidle_cstates *cstates = &datas->cstates[cpu]; - struct cpufreq_pstate *pstate = datas->pstates[cpu].pstate; struct cpuidle_cstate *cstate; struct cpuidle_data *data, *tmp; int nrdata, last_cstate = cstates->last_cstate; @@ -826,9 +919,8 @@ static int store_data(double time, int state, int cpu, /* need indication if CPU is idle or not */ cstates->last_cstate = -1;
- /* update P-state stats if supported */ - if (pstate) - cpu_pstate_running(datas, cpu, time); + /* update P-state stats */ + cpu_pstate_running(datas, cpu, time);
return 0; } @@ -846,9 +938,8 @@ static int store_data(double time, int state, int cpu, cstates->cstate_max = MAX(cstates->cstate_max, state); cstates->last_cstate = state; cstates->wakeirq = NULL; - /* update P-state stats if supported */ - if (pstate) - cpu_pstate_idle(datas, cpu, time); + /* update P-state stats*/ + cpu_pstate_idle(datas, cpu, time);
return 0; } @@ -932,7 +1023,8 @@ static int get_wakeup_irq(struct cpuidle_datas *datas, char *buffer, int count) return -1; }
-static struct cpuidle_datas *idlestat_load(struct program_options *options) +static struct cpuidle_datas *idlestat_load(struct program_options *options, + struct init_pstates *initp, double start_ts, double end_ts) { FILE *f; unsigned int state = 0, freq = 0, cpu = 0, nrcpus = 0; @@ -988,14 +1080,13 @@ static struct cpuidle_datas *idlestat_load(struct program_options *options) return ptrerror("build_cstate_info: out of memory"); }
- datas->pstates = build_pstate_info(nrcpus); + datas->pstates = build_pstate_info(nrcpus, initp, start_ts); if (!datas->pstates) { free(datas->cstates); free(datas); fclose(f); return ptrerror("build_pstate_info: out of memory"); } - datas->nrcpus = nrcpus;
/* read topology information */ @@ -1018,7 +1109,6 @@ static struct cpuidle_datas *idlestat_load(struct program_options *options) } else if (strstr(buffer, "cpu_frequency")) { assert(sscanf(buffer, TRACE_FORMAT, &time, &freq, &cpu) == 3); - assert(datas->pstates[cpu].pstate != NULL); cpu_change_pstate(datas, cpu, freq, time); count++; continue; @@ -1031,6 +1121,9 @@ static struct cpuidle_datas *idlestat_load(struct program_options *options)
fclose(f);
+ /* close all p-state with end timestamp */ + cpu_close_all_pstate(datas, end_ts); + fprintf(stderr, "Log is %lf secs long with %zd events\n", end - begin, count);
@@ -1481,7 +1574,9 @@ int main(int argc, char *argv[], char *const envp[]) { struct cpuidle_datas *datas; struct program_options options; + struct init_pstates *initp = NULL; int args; + double start_ts, end_ts;
args = getoptions(argc, argv, &options); if (args <= 0) @@ -1527,6 +1622,14 @@ int main(int argc, char *argv[], char *const envp[]) if (idlestat_flush_trace()) return -1;
+ /* Get current P-state of all CPUs */ + if (options.display & FREQUENCY_DISPLAY) + initp = build_init_pstates(); + + /* Get timestamp before trace acquisition */ + if (options.display & FREQUENCY_DISPLAY) + start_ts = get_trace_ts(); + /* Start the recording */ if (idlestat_trace_enable(true)) return -1; @@ -1549,6 +1652,17 @@ int main(int argc, char *argv[], char *const envp[]) if (idlestat_trace_enable(false)) return -1;
+ /* Get timestamp after trace acquisition */ + if (options.display & FREQUENCY_DISPLAY) + end_ts = get_trace_ts(); + + /* Emit warning messages when P-state info might be partial */ + if (options.display & FREQUENCY_DISPLAY && + (!initp || start_ts < 0 || end_ts < 0)) + fprintf(stderr, "Unable to get initial P-state," + " beginning timestamp, or ending timestamp!\n" + "P-state statistics data might be partial!\n"); + /* At this point we should have some spurious wake up * at the beginning of the traces and at the end (wake * up all cpus and timer expiration for the timer @@ -1559,7 +1673,7 @@ int main(int argc, char *argv[], char *const envp[]) }
/* Load the idle states information */ - datas = idlestat_load(&options); + datas = idlestat_load(&options, initp, start_ts, end_ts);
if (!datas) return 1; @@ -1590,6 +1704,7 @@ int main(int argc, char *argv[], char *const envp[]) } }
+ release_init_pstates(initp); release_cpu_topo_cstates(); release_cpu_topo_info(); release_pstate_info(datas->pstates, datas->nrcpus); diff --git a/idlestat.h b/idlestat.h index 735f0fe..39ba4d7 100644 --- a/idlestat.h +++ b/idlestat.h @@ -41,6 +41,8 @@ "/sys/devices/system/cpu/cpu%d/cpuidle/state%d/residency" #define CPUFREQ_AVFREQ_PATH_FORMAT \ "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_available_frequencies" +#define CPUFREQ_CURFREQ_PATH_FORMAT \ + "/sys/devices/system/cpu/cpu%d/cpufreq/cpuinfo_cur_freq" #define CPUIDLE_STATENAME_PATH_FORMAT \ "/sys/devices/system/cpu/cpu%d/cpuidle/state%d/name"
@@ -63,6 +65,11 @@ struct cpuidle_cstate { int target_residency; /* -1 if not available */ };
+struct init_pstates { + int nr_cpus; + unsigned int *freqs; +}; + enum IRQ_TYPE { HARD_IRQ = 0, IPI_IRQ, diff --git a/trace.h b/trace.h index bef6703..90b4a6a 100644 --- a/trace.h +++ b/trace.h @@ -33,6 +33,7 @@ #define TRACE_EVENT_PATH TRACE_PATH "/events/enable" #define TRACE_FREE TRACE_PATH "/free_buffer" #define TRACE_FILE TRACE_PATH "/trace" +#define TRACE_STAT_FILE TRACE_PATH "/per_cpu/cpu0/stats" #define TRACE_IDLE_NRHITS_PER_SEC 10000 #define TRACE_IDLE_LENGTH 196 #define TRACE_CPUFREQ_NRHITS_PER_SEC 100