From 273e66baef8bf930959c503041b68411bb42ff80 Mon Sep 17 00:00:00 2001 From: Tvrtko Ursulin Date: Tue, 10 Oct 2017 08:22:30 +0100 Subject: intel-gpu-overlay: Use RAPL PMU for power reading Wire up to the RAPL PMU for GPU energy readings. The only complication is that we have to add code to parse: # cat /sys/devices/power/events/energy-gpu.scale 2.3283064365386962890625e-10 v2: Link with -lm. v3: strtod can handle scientific notation, even though my initial reading of the man page did not spot that. (Chris Wilson) v4: Meson fix. Signed-off-by: Tvrtko Ursulin Reviewed-by: Chris Wilson --- overlay/Makefile.am | 2 +- overlay/meson.build | 2 +- overlay/power.c | 127 ++++++++++++++++++++++++++++++++++++---------------- overlay/power.h | 2 + 4 files changed, 92 insertions(+), 41 deletions(-) (limited to 'overlay') diff --git a/overlay/Makefile.am b/overlay/Makefile.am index cefde2d0..f49f54ac 100644 --- a/overlay/Makefile.am +++ b/overlay/Makefile.am @@ -63,7 +63,7 @@ intel_gpu_overlay_SOURCES += \ intel_gpu_overlay_SOURCES += $(both_x11_sources) -intel_gpu_overlay_LDADD = $(LDADD) -lrt +intel_gpu_overlay_LDADD = $(LDADD) -lrt -lm EXTRA_DIST= \ README \ diff --git a/overlay/meson.build b/overlay/meson.build index ffc011cc..6b479eb8 100644 --- a/overlay/meson.build +++ b/overlay/meson.build @@ -21,7 +21,7 @@ dri2proto = dependency('dri2proto', version : '>= 2.6', required : false) cairo_xlib = dependency('cairo-xlib', required : false) xrandr = dependency('xrandr', version : '>=1.3', required : false) -gpu_overlay_deps = [ realtime, cairo, pciaccess, libdrm, libdrm_intel ] +gpu_overlay_deps = [ realtime, math, cairo, pciaccess, libdrm, libdrm_intel ] both_x11_src = '' diff --git a/overlay/power.c b/overlay/power.c index 805f4ca7..9ac90fde 100644 --- a/overlay/power.c +++ b/overlay/power.c @@ -30,60 +30,107 @@ #include #include #include +#include +#include #include "igt_perf.h" #include "power.h" #include "debugfs.h" -/* XXX Is this exposed through RAPL? */ - -int power_init(struct power *power) +static int +filename_to_buf(const char *filename, char *buf, unsigned int bufsize) { - char buf[4096]; - int fd, len; - - memset(power, 0, sizeof(*power)); - - power->fd = -1; + int fd; + ssize_t ret; - sprintf(buf, "%s/i915_energy_uJ", debugfs_dri_path); - fd = open(buf, 0); + fd = open(filename, O_RDONLY); if (fd < 0) - return power->error = errno; + return -1; - len = read(fd, buf, sizeof(buf)); + ret = read(fd, buf, bufsize - 1); close(fd); + if (ret < 1) + return -1; - if (len < 0) - return power->error = errno; - - buf[len] = '\0'; - if (strtoull(buf, 0, 0) == 0) - return power->error = EINVAL; + buf[ret] = '\0'; return 0; } -static uint64_t file_to_u64(const char *name) +static uint64_t filename_to_u64(const char *filename, int base) { - char buf[4096]; - int fd, len; + char buf[64], *b; - sprintf(buf, "%s/%s", debugfs_dri_path, name); - fd = open(buf, 0); - if (fd < 0) + if (filename_to_buf(filename, buf, sizeof(buf))) return 0; - len = read(fd, buf, sizeof(buf)-1); - close(fd); + /* + * Handle both single integer and key=value formats by skipping + * leading non-digits. + */ + b = buf; + while (*b && !isdigit(*b)) + b++; + + return strtoull(b, NULL, base); +} + +static uint64_t debugfs_file_to_u64(const char *name) +{ + char buf[1024]; + + snprintf(buf, sizeof(buf), "%s/%s", debugfs_dri_path, name); + + return filename_to_u64(buf, 0); +} + +static uint64_t rapl_type_id(void) +{ + return filename_to_u64("/sys/devices/power/type", 10); +} + +static uint64_t rapl_gpu_power(void) +{ + return filename_to_u64("/sys/devices/power/events/energy-gpu", 0); +} - if (len < 0) +static double filename_to_double(const char *filename) +{ + char buf[64]; + + if (filename_to_buf(filename, buf, sizeof(buf))) return 0; - buf[len] = '\0'; + return strtod(buf, NULL); +} + +static double rapl_gpu_power_scale(void) +{ + return filename_to_double("/sys/devices/power/events/energy-gpu.scale"); +} + +int power_init(struct power *power) +{ + uint64_t val; + + memset(power, 0, sizeof(*power)); + + power->fd = igt_perf_open(rapl_type_id(), rapl_gpu_power()); + if (power->fd >= 0) { + power->rapl_scale = rapl_gpu_power_scale(); + + if (power->rapl_scale != NAN) { + power->rapl_scale *= 1e3; /* from nano to micro */ + return 0; + } + } + + val = debugfs_file_to_u64("i915_energy_uJ"); + if (val == 0) + return power->error = EINVAL; - return strtoull(buf, 0, 0); + return 0; } static uint64_t clock_ms_to_u64(void) @@ -93,30 +140,30 @@ static uint64_t clock_ms_to_u64(void) if (clock_gettime(CLOCK_MONOTONIC, &tv) < 0) return 0; - return (uint64_t)tv.tv_sec * 1000 + tv.tv_nsec / 1000000; + return (uint64_t)tv.tv_sec * 1e3 + tv.tv_nsec / 1e6; } int power_update(struct power *power) { - struct power_stat *s = &power->stat[power->count++&1]; - struct power_stat *d = &power->stat[power->count&1]; + struct power_stat *s = &power->stat[power->count++ & 1]; + struct power_stat *d = &power->stat[power->count & 1]; uint64_t d_time; if (power->error) return power->error; - if (power->fd != -1) { + if (power->fd >= 0) { uint64_t data[2]; int len; len = read(power->fd, data, sizeof(data)); - if (len < 0) + if (len != sizeof(data)) return power->error = errno; - s->energy = data[0]; - s->timestamp = data[1] / (1000*1000); + s->energy = llround((double)data[0] * power->rapl_scale); + s->timestamp = data[1] / 1e6; } else { - s->energy = file_to_u64("i915_energy_uJ"); + s->energy = debugfs_file_to_u64("i915_energy_uJ") / 1e3; s->timestamp = clock_ms_to_u64(); } @@ -124,7 +171,9 @@ int power_update(struct power *power) return EAGAIN; d_time = s->timestamp - d->timestamp; - power->power_mW = (s->energy - d->energy) / d_time; + power->power_mW = round((double)(s->energy - d->energy) * + (1e3f / d_time)); power->new_sample = 1; + return 0; } diff --git a/overlay/power.h b/overlay/power.h index bf8346ce..28abfc32 100644 --- a/overlay/power.h +++ b/overlay/power.h @@ -39,6 +39,8 @@ struct power { int new_sample; uint64_t power_mW; + + double rapl_scale; }; int power_init(struct power *power); -- cgit v1.2.3