overlay: read rc6 status from perf

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/overlay/overlay.c b/overlay/overlay.c
index d1eb158..1cdf739 100644 (file)
--- a/overlay/overlay.c
+++ b/overlay/overlay.c
@@ -582,28 +582,31 @@ static void show_gpu_freq(struct overlay_context *ctx, struct overlay_gpu_freq *
                len = sprintf(buf, "RC6: %d%%", gf->rc6.rc6_combined);
                cairo_set_source_rgba(ctx->cr, 1, 1, 1, 1);
                cairo_move_to(ctx->cr, PAD, y);
-               if (gf->rc6.rc6_combined && !is_power_of_two(gf->rc6.enabled)) {
+               if (gf->rc6.rc6_combined) {
                        int need_comma = 0;
+                       int rewind = len;
                        len += sprintf(buf + len, " (");
-                       if (gf->rc6.enabled & 1) {
+                       if (gf->rc6.rc6) {
                                len += sprintf(buf + len, "%src6=%d%%",
                                               need_comma ? ", " : "",
                                               gf->rc6.rc6);
-                               need_comma = 1;
+                               need_comma++;
                        }
-                       if (gf->rc6.enabled & 2) {
+                       if (gf->rc6.rc6p) {
                                len += sprintf(buf + len, "%src6p=%d%%",
                                               need_comma ? ", " : "",
                                               gf->rc6.rc6p);
-                               need_comma = 1;
+                               need_comma++;
                        }
-                       if (gf->rc6.enabled & 4) {
+                       if (gf->rc6.rc6pp) {
                                len += sprintf(buf + len, "%src6pp=%d%%",
                                               need_comma ? ", " : "",
                                               gf->rc6.rc6pp);
-                               need_comma = 1;
+                               need_comma++;
                        }
                        sprintf(buf + len, ")");
+                       if (need_comma <= 1)
+                               buf[rewind] = '\0';
                }
                cairo_show_text(ctx->cr, buf);
                y += 14;

diff --git a/overlay/perf.h b/overlay/perf.h
index e2be0f7..c44e65f 100644 (file)
--- a/overlay/perf.h
+++ b/overlay/perf.h
@@ -35,6 +35,10 @@
 #define I915_PERF_ENERGY 34
 #define I915_PERF_INTERRUPTS 35
 
+#define I915_PERF_RC6_RESIDENCY                40
+#define I915_PERF_RC6p_RESIDENCY       41
+#define I915_PERF_RC6pp_RESIDENCY      42
+
 static inline int
 perf_event_open(struct perf_event_attr *attr,
                pid_t pid,

diff --git a/overlay/rc6.c b/overlay/rc6.c
index 500639a..d7047c2 100644 (file)
--- a/overlay/rc6.c
+++ b/overlay/rc6.c
@@ -32,17 +32,58 @@
 #include <errno.h>
 
 #include "rc6.h"
+#include "perf.h"
 
-int rc6_init(struct rc6 *rc6)
+static int perf_i915_open(int config, int group)
+{
+       struct perf_event_attr attr;
+
+       memset(&attr, 0, sizeof (attr));
+
+       attr.type = i915_type_id();
+       if (attr.type == 0)
+               return -ENOENT;
+       attr.config = config;
+
+       attr.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED;
+       if (group == -1)
+               attr.read_format |= PERF_FORMAT_GROUP;
+
+       return perf_event_open(&attr, -1, 0, group, 0);
+}
+
+#define RC6    (1<<0)
+#define RC6p   (1<<1)
+#define RC6pp  (1<<2)
+
+static int perf_open(unsigned *flags)
 {
-       struct stat st;
        int fd;
 
+       fd = perf_i915_open(I915_PERF_RC6_RESIDENCY, -1);
+       if (fd < 0)
+               return -1;
+
+       *flags |= RC6;
+       if (perf_i915_open(I915_PERF_RC6p_RESIDENCY, fd) >= 0)
+               *flags |= RC6p;
+
+       if (perf_i915_open(I915_PERF_RC6pp_RESIDENCY, fd) >= 0)
+               *flags |= RC6pp;
+
+       return fd;
+}
+
+int rc6_init(struct rc6 *rc6)
+{
        memset(rc6, 0, sizeof(*rc6));
 
-       fd = stat("/sys/class/drm/card0/power", &st);
-       if (fd == -1)
-               return rc6->error = errno;
+       rc6->fd = perf_open(&rc6->flags);
+       if (rc6->fd == -1) {
+               struct stat st;
+               if (stat("/sys/class/drm/card0/power", &st) < 0)
+                       return rc6->error = errno;
+       }
 
        return 0;
 }
@@ -54,13 +95,13 @@ static uint64_t file_to_u64(const char *path)
 
        fd = open(path, 0);
        if (fd < 0)
-               return 0;
+               return -1;
 
        len = read(fd, buf, sizeof(buf)-1);
        close(fd);
 
        if (len < 0)
-               return 0;
+               return -1;
 
        buf[len] = '\0';
 
@@ -82,37 +123,57 @@ int rc6_update(struct rc6 *rc6)
        struct rc6_stat *s = &rc6->stat[rc6->count++&1];
        struct rc6_stat *d = &rc6->stat[rc6->count&1];
        uint64_t d_time, d_rc6, d_rc6p, d_rc6pp;
-       struct stat st;
 
        if (rc6->error)
                return rc6->error;
 
-       if (stat("/sys/class/drm/card0/power/rc6_residency_ms", &st) < 0)
-               return rc6->error = ENOENT;
+       if (rc6->fd == -1) {
+               struct stat st;
 
-       rc6->enabled = file_to_u64("/sys/class/drm/card0/power/rc6_enable");
-       if (rc6->enabled == 0)
-               return EAGAIN;
+               if (stat("/sys/class/drm/card0/power/rc6_residency_ms", &st) < 0)
+                       return rc6->error = ENOENT;
+
+               s->rc6_residency = file_to_u64("/sys/class/drm/card0/power/rc6_residency_ms");
+               s->rc6p_residency = file_to_u64("/sys/class/drm/card0/power/rc6p_residency_ms");
+               s->rc6pp_residency = file_to_u64("/sys/class/drm/card0/power/rc6pp_residency_ms");
+               s->timestamp = clock_ms_to_u64();
+       } else {
+               uint64_t data[5];
+               int len;
 
-       s->rc6_residency = file_to_u64("/sys/class/drm/card0/power/rc6_residency_ms");
-       s->rc6p_residency = file_to_u64("/sys/class/drm/card0/power/rc6p_residency_ms");
-       s->rc6pp_residency = file_to_u64("/sys/class/drm/card0/power/rc6pp_residency_ms");
-       s->timestamp = clock_ms_to_u64();
+               len = read(rc6->fd, data, sizeof(data));
+               if (len < 0)
+                       return rc6->error = errno;
+
+               s->timestamp = data[1] / (1000*1000);
+
+               len = 2;
+               if (rc6->flags & RC6)
+                       s->rc6_residency = data[len++];
+               if (rc6->flags & RC6p)
+                       s->rc6p_residency = data[len++];
+               if (rc6->flags & RC6pp)
+                       s->rc6pp_residency = data[len++];
+       }
 
        if (rc6->count == 1)
                return EAGAIN;
 
        d_time = s->timestamp - d->timestamp;
+       if (d_time == 0) {
+               rc6->count--;
+               return EAGAIN;
+       }
 
        d_rc6 = s->rc6_residency - d->rc6_residency;
-       rc6->rc6 = 100 * d_rc6 / d_time;
+       rc6->rc6 = (100 * d_rc6 + d_time/2) / d_time;
 
        d_rc6p = s->rc6p_residency - d->rc6p_residency;
-       rc6->rc6p = 100 * d_rc6p / d_time;
+       rc6->rc6p = (100 * d_rc6p + d_time/2) / d_time;
 
        d_rc6pp = s->rc6pp_residency - d->rc6pp_residency;
-       rc6->rc6pp = 100 * d_rc6pp / d_time;
+       rc6->rc6pp = (100 * d_rc6pp + d_time/2) / d_time;
 
-       rc6->rc6_combined = 100 * (d_rc6 + d_rc6p + d_rc6pp) / d_time;
+       rc6->rc6_combined = (100 * (d_rc6 + d_rc6p + d_rc6pp) + d_time/2) / d_time;
        return 0;
 }

diff --git a/overlay/rc6.h b/overlay/rc6.h
index 7597e3b..faffba9 100644 (file)
--- a/overlay/rc6.h
+++ b/overlay/rc6.h
@@ -35,10 +35,11 @@ struct rc6 {
                uint64_t timestamp;
        } stat[2];
 
+       int fd;
        int count;
        int error;
 
-       unsigned enabled;
+       unsigned flags;
 
        uint8_t rc6;
        uint8_t rc6p;