--- /dev/null
+/*
+ * Copyright (C) 2013 Red Hat
+ * Author: Rob Clark <robdclark@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* For profiling, userspace can:
+ *
+ * tail -f /sys/kernel/debug/dri/<minor>/gpu
+ *
+ * This will enable performance counters/profiling to track the busy time
+ * and any gpu specific performance counters that are supported.
+ */
+
+#ifdef CONFIG_DEBUG_FS
+
+#include <linux/debugfs.h>
+
+#include "msm_drv.h"
+#include "msm_gpu.h"
+
+struct msm_perf_state {
+ struct drm_device *dev;
+
+ bool open;
+ int cnt;
+ struct mutex read_lock;
+
+ char buf[256];
+ int buftot, bufpos;
+
+ unsigned long next_jiffies;
+
+ struct dentry *ent;
+ struct drm_info_node *node;
+};
+
+#define SAMPLE_TIME (HZ/4)
+
+/* wait for next sample time: */
+static int wait_sample(struct msm_perf_state *perf)
+{
+ unsigned long start_jiffies = jiffies;
+
+ if (time_after(perf->next_jiffies, start_jiffies)) {
+ unsigned long remaining_jiffies =
+ perf->next_jiffies - start_jiffies;
+ int ret = schedule_timeout_interruptible(remaining_jiffies);
+ if (ret > 0) {
+ /* interrupted */
+ return -ERESTARTSYS;
+ }
+ }
+ perf->next_jiffies += SAMPLE_TIME;
+ return 0;
+}
+
+static int refill_buf(struct msm_perf_state *perf)
+{
+ struct msm_drm_private *priv = perf->dev->dev_private;
+ struct msm_gpu *gpu = priv->gpu;
+ char *ptr = perf->buf;
+ int rem = sizeof(perf->buf);
+ int i, n;
+
+ if ((perf->cnt++ % 32) == 0) {
+ /* Header line: */
+ n = snprintf(ptr, rem, "%%BUSY");
+ ptr += n;
+ rem -= n;
+
+ for (i = 0; i < gpu->num_perfcntrs; i++) {
+ const struct msm_gpu_perfcntr *perfcntr = &gpu->perfcntrs[i];
+ n = snprintf(ptr, rem, "\t%s", perfcntr->name);
+ ptr += n;
+ rem -= n;
+ }
+ } else {
+ /* Sample line: */
+ uint32_t activetime = 0, totaltime = 0;
+ uint32_t cntrs[5];
+ uint32_t val;
+ int ret;
+
+ /* sleep until next sample time: */
+ ret = wait_sample(perf);
+ if (ret)
+ return ret;
+
+ ret = msm_gpu_perfcntr_sample(gpu, &activetime, &totaltime,
+ ARRAY_SIZE(cntrs), cntrs);
+ if (ret < 0)
+ return ret;
+
+ val = totaltime ? 1000 * activetime / totaltime : 0;
+ n = snprintf(ptr, rem, "%3d.%d%%", val / 10, val % 10);
+ ptr += n;
+ rem -= n;
+
+ for (i = 0; i < ret; i++) {
+ /* cycle counters (I think).. convert to MHz.. */
+ val = cntrs[i] / 10000;
+ n = snprintf(ptr, rem, "\t%5d.%02d",
+ val / 100, val % 100);
+ ptr += n;
+ rem -= n;
+ }
+ }
+
+ n = snprintf(ptr, rem, "\n");
+ ptr += n;
+ rem -= n;
+
+ perf->bufpos = 0;
+ perf->buftot = ptr - perf->buf;
+
+ return 0;
+}
+
+static ssize_t perf_read(struct file *file, char __user *buf,
+ size_t sz, loff_t *ppos)
+{
+ struct msm_perf_state *perf = file->private_data;
+ int n = 0, ret;
+
+ mutex_lock(&perf->read_lock);
+
+ if (perf->bufpos >= perf->buftot) {
+ ret = refill_buf(perf);
+ if (ret)
+ goto out;
+ }
+
+ n = min((int)sz, perf->buftot - perf->bufpos);
+ ret = copy_to_user(buf, &perf->buf[perf->bufpos], n);
+ if (ret)
+ goto out;
+
+ perf->bufpos += n;
+ *ppos += n;
+
+out:
+ mutex_unlock(&perf->read_lock);
+ if (ret)
+ return ret;
+ return n;
+}
+
+static int perf_open(struct inode *inode, struct file *file)
+{
+ struct msm_perf_state *perf = inode->i_private;
+ struct drm_device *dev = perf->dev;
+ struct msm_drm_private *priv = dev->dev_private;
+ struct msm_gpu *gpu = priv->gpu;
+ int ret = 0;
+
+ mutex_lock(&dev->struct_mutex);
+
+ if (perf->open || !gpu) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ file->private_data = perf;
+ perf->open = true;
+ perf->cnt = 0;
+ perf->buftot = 0;
+ perf->bufpos = 0;
+ msm_gpu_perfcntr_start(gpu);
+ perf->next_jiffies = jiffies + SAMPLE_TIME;
+
+out:
+ mutex_unlock(&dev->struct_mutex);
+ return ret;
+}
+
+static int perf_release(struct inode *inode, struct file *file)
+{
+ struct msm_perf_state *perf = inode->i_private;
+ struct msm_drm_private *priv = perf->dev->dev_private;
+ msm_gpu_perfcntr_stop(priv->gpu);
+ perf->open = false;
+ return 0;
+}
+
+
+static const struct file_operations perf_debugfs_fops = {
+ .owner = THIS_MODULE,
+ .open = perf_open,
+ .read = perf_read,
+ .llseek = no_llseek,
+ .release = perf_release,
+};
+
+int msm_perf_debugfs_init(struct drm_minor *minor)
+{
+ struct msm_drm_private *priv = minor->dev->dev_private;
+ struct msm_perf_state *perf;
+
+ /* only create on first minor: */
+ if (priv->perf)
+ return 0;
+
+ perf = kzalloc(sizeof(*perf), GFP_KERNEL);
+ if (!perf)
+ return -ENOMEM;
+
+ perf->dev = minor->dev;
+
+ mutex_init(&perf->read_lock);
+ priv->perf = perf;
+
+ perf->node = kzalloc(sizeof(*perf->node), GFP_KERNEL);
+ if (!perf->node)
+ goto fail;
+
+ perf->ent = debugfs_create_file("perf", S_IFREG | S_IRUGO,
+ minor->debugfs_root, perf, &perf_debugfs_fops);
+ if (!perf->ent) {
+ DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s/perf\n",
+ minor->debugfs_root->d_name.name);
+ goto fail;
+ }
+
+ perf->node->minor = minor;
+ perf->node->dent = perf->ent;
+ perf->node->info_ent = NULL;
+
+ mutex_lock(&minor->debugfs_lock);
+ list_add(&perf->node->list, &minor->debugfs_list);
+ mutex_unlock(&minor->debugfs_lock);
+
+ return 0;
+
+fail:
+ msm_perf_debugfs_cleanup(minor);
+ return -1;
+}
+
+void msm_perf_debugfs_cleanup(struct drm_minor *minor)
+{
+ struct msm_drm_private *priv = minor->dev->dev_private;
+ struct msm_perf_state *perf = priv->perf;
+
+ if (!perf)
+ return;
+
+ priv->perf = NULL;
+
+ debugfs_remove(perf->ent);
+
+ if (perf->node) {
+ mutex_lock(&minor->debugfs_lock);
+ list_del(&perf->node->list);
+ mutex_unlock(&minor->debugfs_lock);
+ kfree(perf->node);
+ }
+
+ mutex_destroy(&perf->read_lock);
+
+ kfree(perf);
+}
+
+#endif
Code Review / kvmfornfv.git / blobdiff