diff options
Diffstat (limited to 'drivers/gpu/drm/msm/msm_perf.c')
-rw-r--r-- | drivers/gpu/drm/msm/msm_perf.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/drivers/gpu/drm/msm/msm_perf.c b/drivers/gpu/drm/msm/msm_perf.c new file mode 100644 index 000000000000..830857c47c86 --- /dev/null +++ b/drivers/gpu/drm/msm/msm_perf.c @@ -0,0 +1,275 @@ +/* + * 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 |