diff options
Diffstat (limited to 'drivers/base/sync.c')
| -rw-r--r-- | drivers/base/sync.c | 800 |
1 files changed, 800 insertions, 0 deletions
diff --git a/drivers/base/sync.c b/drivers/base/sync.c new file mode 100644 index 00000000000..cc40e4c9e65 --- /dev/null +++ b/drivers/base/sync.c @@ -0,0 +1,800 @@ +/* + * drivers/base/sync.c + * + * Copyright (C) 2012 Google, Inc. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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. + * + */ + +#include <linux/debugfs.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/kernel.h> +#include <linux/poll.h> +#include <linux/sched.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/sync.h> +#include <linux/uaccess.h> + +#include <linux/anon_inodes.h> + +static void sync_fence_signal_pt(struct sync_pt *pt); +static int _sync_pt_has_signaled(struct sync_pt *pt); + +static LIST_HEAD(sync_timeline_list_head); +static DEFINE_SPINLOCK(sync_timeline_list_lock); + +static LIST_HEAD(sync_fence_list_head); +static DEFINE_SPINLOCK(sync_fence_list_lock); + +struct sync_timeline *sync_timeline_create(const struct sync_timeline_ops *ops, + int size, const char *name) +{ + struct sync_timeline *obj; + unsigned long flags; + + if (size < sizeof(struct sync_timeline)) + return NULL; + + obj = kzalloc(size, GFP_KERNEL); + if (obj == NULL) + return NULL; + + obj->ops = ops; + strlcpy(obj->name, name, sizeof(obj->name)); + + INIT_LIST_HEAD(&obj->child_list_head); + spin_lock_init(&obj->child_list_lock); + + INIT_LIST_HEAD(&obj->active_list_head); + spin_lock_init(&obj->active_list_lock); + + spin_lock_irqsave(&sync_timeline_list_lock, flags); + list_add_tail(&obj->sync_timeline_list, &sync_timeline_list_head); + spin_unlock_irqrestore(&sync_timeline_list_lock, flags); + + return obj; +} + +static void sync_timeline_free(struct sync_timeline *obj) +{ + unsigned long flags; + + if (obj->ops->release_obj) + obj->ops->release_obj(obj); + + spin_lock_irqsave(&sync_timeline_list_lock, flags); + list_del(&obj->sync_timeline_list); + spin_unlock_irqrestore(&sync_timeline_list_lock, flags); + + kfree(obj); +} + +void sync_timeline_destroy(struct sync_timeline *obj) +{ + unsigned long flags; + bool needs_freeing; + + spin_lock_irqsave(&obj->child_list_lock, flags); + obj->destroyed = true; + needs_freeing = list_empty(&obj->child_list_head); + spin_unlock_irqrestore(&obj->child_list_lock, flags); + + if (needs_freeing) + sync_timeline_free(obj); + else + sync_timeline_signal(obj); +} + +static void sync_timeline_add_pt(struct sync_timeline *obj, struct sync_pt *pt) +{ + unsigned long flags; + + pt->parent = obj; + + spin_lock_irqsave(&obj->child_list_lock, flags); + list_add_tail(&pt->child_list, &obj->child_list_head); + spin_unlock_irqrestore(&obj->child_list_lock, flags); +} + +static void sync_timeline_remove_pt(struct sync_pt *pt) +{ + struct sync_timeline *obj = pt->parent; + unsigned long flags; + bool needs_freeing; + + spin_lock_irqsave(&obj->active_list_lock, flags); + if (!list_empty(&pt->active_list)) + list_del_init(&pt->active_list); + spin_unlock_irqrestore(&obj->active_list_lock, flags); + + spin_lock_irqsave(&obj->child_list_lock, flags); + list_del(&pt->child_list); + needs_freeing = obj->destroyed && list_empty(&obj->child_list_head); + spin_unlock_irqrestore(&obj->child_list_lock, flags); + + if (needs_freeing) + sync_timeline_free(obj); +} + +void sync_timeline_signal(struct sync_timeline *obj) +{ + unsigned long flags; + LIST_HEAD(signaled_pts); + struct list_head *pos, *n; + + spin_lock_irqsave(&obj->active_list_lock, flags); + + list_for_each_safe(pos, n, &obj->active_list_head) { + struct sync_pt *pt = + container_of(pos, struct sync_pt, active_list); + + if (_sync_pt_has_signaled(pt)) + list_move(pos, &signaled_pts); + } + + spin_unlock_irqrestore(&obj->active_list_lock, flags); + + list_for_each_safe(pos, n, &signaled_pts) { + struct sync_pt *pt = + container_of(pos, struct sync_pt, active_list); + + list_del_init(pos); + sync_fence_signal_pt(pt); + } +} + +struct sync_pt *sync_pt_create(struct sync_timeline *parent, int size) +{ + struct sync_pt *pt; + + if (size < sizeof(struct sync_pt)) + return NULL; + + pt = kzalloc(size, GFP_KERNEL); + if (pt == NULL) + return NULL; + + INIT_LIST_HEAD(&pt->active_list); + sync_timeline_add_pt(parent, pt); + + return pt; +} + +void sync_pt_free(struct sync_pt *pt) +{ + if (pt->parent->ops->free_pt) + pt->parent->ops->free_pt(pt); + + sync_timeline_remove_pt(pt); + + kfree(pt); +} + +/* call with pt->parent->active_list_lock held */ +static int _sync_pt_has_signaled(struct sync_pt *pt) +{ + int old_status = pt->status; + + if (!pt->status) + pt->status = pt->parent->ops->has_signaled(pt); + + if (!pt->status && pt->parent->destroyed) + pt->status = -ENOENT; + + if (pt->status != old_status) + pt->timestamp = ktime_get(); + + return pt->status; +} + +static struct sync_pt *sync_pt_dup(struct sync_pt *pt) +{ + return pt->parent->ops->dup(pt); +} + +/* Adds a sync pt to the active queue. Called when added to a fence */ +static void sync_pt_activate(struct sync_pt *pt) +{ + struct sync_timeline *obj = pt->parent; + unsigned long flags; + int err; + + spin_lock_irqsave(&obj->active_list_lock, flags); + + err = _sync_pt_has_signaled(pt); + if (err != 0) + goto out; + + list_add_tail(&pt->active_list, &obj->active_list_head); + +out: + spin_unlock_irqrestore(&obj->active_list_lock, flags); +} + +static int sync_fence_release(struct inode *inode, struct file *file); +static unsigned int sync_fence_poll(struct file *file, poll_table *wait); +static long sync_fence_ioctl(struct file *file, unsigned int cmd, + unsigned long arg); + + +static const struct file_operations sync_fence_fops = { + .release = sync_fence_release, + .poll = sync_fence_poll, + .unlocked_ioctl = sync_fence_ioctl, +}; + +static struct sync_fence *sync_fence_alloc(const char *name) +{ + struct sync_fence *fence; + unsigned long flags; + + fence = kzalloc(sizeof(struct sync_fence), GFP_KERNEL); + if (fence == NULL) + return NULL; + + fence->file = anon_inode_getfile("sync_fence", &sync_fence_fops, + fence, 0); + if (fence->file == NULL) + goto err; + + strlcpy(fence->name, name, sizeof(fence->name)); + + INIT_LIST_HEAD(&fence->pt_list_head); + INIT_LIST_HEAD(&fence->waiter_list_head); + spin_lock_init(&fence->waiter_list_lock); + + init_waitqueue_head(&fence->wq); + + spin_lock_irqsave(&sync_fence_list_lock, flags); + list_add_tail(&fence->sync_fence_list, &sync_fence_list_head); + spin_unlock_irqrestore(&sync_fence_list_lock, flags); + + return fence; + +err: + kfree(fence); + return NULL; +} + +/* TODO: implement a create which takes more that one sync_pt */ +struct sync_fence *sync_fence_create(const char *name, struct sync_pt *pt) +{ + struct sync_fence *fence; + + if (pt->fence) + return NULL; + + fence = sync_fence_alloc(name); + if (fence == NULL) + return NULL; + + pt->fence = fence; + list_add(&pt->pt_list, &fence->pt_list_head); + sync_pt_activate(pt); + + return fence; +} + +static int sync_fence_copy_pts(struct sync_fence *dst, struct sync_fence *src) +{ + struct list_head *pos; + + list_for_each(pos, &src->pt_list_head) { + struct sync_pt *orig_pt = + container_of(pos, struct sync_pt, pt_list); + struct sync_pt *new_pt = sync_pt_dup(orig_pt); + + if (new_pt == NULL) + return -ENOMEM; + + new_pt->fence = dst; + list_add(&new_pt->pt_list, &dst->pt_list_head); + sync_pt_activate(new_pt); + } + + return 0; +} + +static void sync_fence_free_pts(struct sync_fence *fence) +{ + struct list_head *pos, *n; + + list_for_each_safe(pos, n, &fence->pt_list_head) { + struct sync_pt *pt = container_of(pos, struct sync_pt, pt_list); + sync_pt_free(pt); + } +} + +struct sync_fence *sync_fence_fdget(int fd) +{ + struct file *file = fget(fd); + + if (file == NULL) + return NULL; + + if (file->f_op != &sync_fence_fops) + goto err; + + return file->private_data; + +err: + fput(file); + return NULL; +} + +void sync_fence_put(struct sync_fence *fence) +{ + fput(fence->file); +} + +void sync_fence_install(struct sync_fence *fence, int fd) +{ + fd_install(fd, fence->file); +} + +static int sync_fence_get_status(struct sync_fence *fence) +{ + struct list_head *pos; + int status = 1; + + list_for_each(pos, &fence->pt_list_head) { + struct sync_pt *pt = container_of(pos, struct sync_pt, pt_list); + int pt_status = pt->status; + + if (pt_status < 0) { + status = pt_status; + break; + } else if (status == 1) { + status = pt_status; + } + } + + return status; +} + +struct sync_fence *sync_fence_merge(const char *name, + struct sync_fence *a, struct sync_fence *b) +{ + struct sync_fence *fence; + int err; + + fence = sync_fence_alloc(name); + if (fence == NULL) + return NULL; + + err = sync_fence_copy_pts(fence, a); + if (err < 0) + goto err; + + err = sync_fence_copy_pts(fence, b); + if (err < 0) + goto err; + + fence->status = sync_fence_get_status(fence); + + return fence; +err: + sync_fence_free_pts(fence); + kfree(fence); + return NULL; +} + +static void sync_fence_signal_pt(struct sync_pt *pt) +{ + LIST_HEAD(signaled_waiters); + struct sync_fence *fence = pt->fence; + struct list_head *pos; + struct list_head *n; + unsigned long flags; + int status; + + status = sync_fence_get_status(fence); + + spin_lock_irqsave(&fence->waiter_list_lock, flags); + /* + * this should protect against two threads racing on the signaled + * false -> true transition + */ + if (status && !fence->status) { + list_for_each_safe(pos, n, &fence->waiter_list_head) + list_move(pos, &signaled_waiters); + + fence->status = status; + } else { + status = 0; + } + spin_unlock_irqrestore(&fence->waiter_list_lock, flags); + + if (status) { + list_for_each_safe(pos, n, &signaled_waiters) { + struct sync_fence_waiter *waiter = + container_of(pos, struct sync_fence_waiter, + waiter_list); + + waiter->callback(fence, waiter->callback_data); + list_del(pos); + kfree(waiter); + } + wake_up(&fence->wq); + } +} + +int sync_fence_wait_async(struct sync_fence *fence, + void (*callback)(struct sync_fence *, void *data), + void *callback_data) +{ + struct sync_fence_waiter *waiter; + unsigned long flags; + int err = 0; + + waiter = kzalloc(sizeof(struct sync_fence_waiter), GFP_KERNEL); + if (waiter == NULL) + return -ENOMEM; + + waiter->callback = callback; + waiter->callback_data = callback_data; + + spin_lock_irqsave(&fence->waiter_list_lock, flags); + + if (fence->status) { + kfree(waiter); + err = fence->status; + goto out; + } + + list_add_tail(&waiter->waiter_list, &fence->waiter_list_head); +out: + spin_unlock_irqrestore(&fence->waiter_list_lock, flags); + + return err; +} + +int sync_fence_wait(struct sync_fence *fence, long timeout) +{ + int err; + + if (timeout) { + timeout = msecs_to_jiffies(timeout); + err = wait_event_interruptible_timeout(fence->wq, + fence->status != 0, + timeout); + } else { + err = wait_event_interruptible(fence->wq, fence->status != 0); + } + + if (err < 0) + return err; + + if (fence->status < 0) + return fence->status; + + if (fence->status == 0) + return -ETIME; + + return 0; +} + +static int sync_fence_release(struct inode *inode, struct file *file) +{ + struct sync_fence *fence = file->private_data; + unsigned long flags; + + sync_fence_free_pts(fence); + + spin_lock_irqsave(&sync_fence_list_lock, flags); + list_del(&fence->sync_fence_list); + spin_unlock_irqrestore(&sync_fence_list_lock, flags); + + kfree(fence); + + return 0; +} + +static unsigned int sync_fence_poll(struct file *file, poll_table *wait) +{ + struct sync_fence *fence = file->private_data; + + poll_wait(file, &fence->wq, wait); + + if (fence->status == 1) + return POLLIN; + else if (fence->status < 0) + return POLLERR; + else + return 0; +} + +static long sync_fence_ioctl_wait(struct sync_fence *fence, unsigned long arg) +{ + __u32 value; + + if (copy_from_user(&value, (void __user *)arg, sizeof(value))) + return -EFAULT; + + return sync_fence_wait(fence, value); +} + +static long sync_fence_ioctl_merge(struct sync_fence *fence, unsigned long arg) +{ + int fd = get_unused_fd(); + int err; + struct sync_fence *fence2, *fence3; + struct sync_merge_data data; + + if (copy_from_user(&data, (void __user *)arg, sizeof(data))) + return -EFAULT; + + fence2 = sync_fence_fdget(data.fd2); + if (fence2 == NULL) { + err = -ENOENT; + goto err_put_fd; + } + + data.name[sizeof(data.name) - 1] = '\0'; + fence3 = sync_fence_merge(data.name, fence, fence2); + if (fence3 == NULL) { + err = -ENOMEM; + goto err_put_fence2; + } + + data.fence = fd; + if (copy_to_user((void __user *)arg, &data, sizeof(data))) { + err = -EFAULT; + goto err_put_fence3; + } + + sync_fence_install(fence3, fd); + sync_fence_put(fence2); + return 0; + +err_put_fence3: + sync_fence_put(fence3); + +err_put_fence2: + sync_fence_put(fence2); + +err_put_fd: + put_unused_fd(fd); + return err; +} + +static int sync_fill_pt_info(struct sync_pt *pt, void *data, int size) +{ + struct sync_pt_info *info = data; + int ret; + + if (size < sizeof(struct sync_pt_info)) + return -ENOMEM; + + info->len = sizeof(struct sync_pt_info); + + if (pt->parent->ops->fill_driver_data) { + ret = pt->parent->ops->fill_driver_data(pt, info->driver_data, + size - sizeof(*info)); + if (ret < 0) + return ret; + + info->len += ret; + } + + strlcpy(info->obj_name, pt->parent->name, sizeof(info->obj_name)); + strlcpy(info->driver_name, pt->parent->ops->driver_name, + sizeof(info->driver_name)); + info->status = pt->status; + info->timestamp_ns = ktime_to_ns(pt->timestamp); + + return info->len; +} + +static long sync_fence_ioctl_fence_info(struct sync_fence *fence, + unsigned long arg) +{ + struct sync_fence_info_data *data; + struct list_head *pos; + __u32 size; + __u32 len = 0; + int ret; + + if (copy_from_user(&size, (void __user *)arg, sizeof(size))) + return -EFAULT; + + if (size < sizeof(struct sync_fence_info_data)) + return -EINVAL; + + if (size > 4096) + size = 4096; + + data = kzalloc(size, GFP_KERNEL); + if (data == NULL) + return -ENOMEM; + + strlcpy(data->name, fence->name, sizeof(data->name)); + data->status = fence->status; + len = sizeof(struct sync_fence_info_data); + + list_for_each(pos, &fence->pt_list_head) { + struct sync_pt *pt = + container_of(pos, struct sync_pt, pt_list); + + ret = sync_fill_pt_info(pt, (u8 *)data + len, size - len); + + if (ret < 0) + goto out; + + len += ret; + } + + data->len = len; + + if (copy_to_user((void __user *)arg, data, len)) + ret = -EFAULT; + else + ret = 0; + +out: + kfree(data); + + return ret; +} + +static long sync_fence_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct sync_fence *fence = file->private_data; + switch (cmd) { + case SYNC_IOC_WAIT: + return sync_fence_ioctl_wait(fence, arg); + + case SYNC_IOC_MERGE: + return sync_fence_ioctl_merge(fence, arg); + + case SYNC_IOC_FENCE_INFO: + return sync_fence_ioctl_fence_info(fence, arg); + + default: + return -ENOTTY; + } +} + +#ifdef CONFIG_DEBUG_FS +static const char *sync_status_str(int status) +{ + if (status > 0) + return "signaled"; + else if (status == 0) + return "active"; + else + return "error"; +} + +static void sync_print_pt(struct seq_file *s, struct sync_pt *pt, bool fence) +{ + int status = pt->status; + seq_printf(s, " %s%spt %s", + fence ? pt->parent->name : "", + fence ? "_" : "", + sync_status_str(status)); + if (pt->status) { + struct timeval tv = ktime_to_timeval(pt->timestamp); + seq_printf(s, "@%ld.%06ld", tv.tv_sec, tv.tv_usec); + } + + if (pt->parent->ops->print_pt) { + seq_printf(s, ": "); + pt->parent->ops->print_pt(s, pt); + } + + seq_printf(s, "\n"); +} + +static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj) +{ + struct list_head *pos; + unsigned long flags; + + seq_printf(s, "%s %s", obj->name, obj->ops->driver_name); + + if (obj->ops->print_obj) { + seq_printf(s, ": "); + obj->ops->print_obj(s, obj); + } + + seq_printf(s, "\n"); + + spin_lock_irqsave(&obj->child_list_lock, flags); + list_for_each(pos, &obj->child_list_head) { + struct sync_pt *pt = + container_of(pos, struct sync_pt, child_list); + sync_print_pt(s, pt, false); + } + spin_unlock_irqrestore(&obj->child_list_lock, flags); +} + +static void sync_print_fence(struct seq_file *s, struct sync_fence *fence) +{ + struct list_head *pos; + unsigned long flags; + + seq_printf(s, "%s: %s\n", fence->name, sync_status_str(fence->status)); + + list_for_each(pos, &fence->pt_list_head) { + struct sync_pt *pt = + container_of(pos, struct sync_pt, pt_list); + sync_print_pt(s, pt, true); + } + + spin_lock_irqsave(&fence->waiter_list_lock, flags); + list_for_each(pos, &fence->waiter_list_head) { + struct sync_fence_waiter *waiter = + container_of(pos, struct sync_fence_waiter, + waiter_list); + + seq_printf(s, "waiter %pF %p\n", waiter->callback, + waiter->callback_data); + } + spin_unlock_irqrestore(&fence->waiter_list_lock, flags); +} + +static int sync_debugfs_show(struct seq_file *s, void *unused) +{ + unsigned long flags; + struct list_head *pos; + + seq_printf(s, "objs:\n--------------\n"); + + spin_lock_irqsave(&sync_timeline_list_lock, flags); + list_for_each(pos, &sync_timeline_list_head) { + struct sync_timeline *obj = + container_of(pos, struct sync_timeline, + sync_timeline_list); + + sync_print_obj(s, obj); + seq_printf(s, "\n"); + } + spin_unlock_irqrestore(&sync_timeline_list_lock, flags); + + seq_printf(s, "fences:\n--------------\n"); + + spin_lock_irqsave(&sync_fence_list_lock, flags); + list_for_each(pos, &sync_fence_list_head) { + struct sync_fence *fence = + container_of(pos, struct sync_fence, sync_fence_list); + + sync_print_fence(s, fence); + seq_printf(s, "\n"); + } + spin_unlock_irqrestore(&sync_fence_list_lock, flags); + return 0; +} + +static int sync_debugfs_open(struct inode *inode, struct file *file) +{ + return single_open(file, sync_debugfs_show, inode->i_private); +} + +static const struct file_operations sync_debugfs_fops = { + .open = sync_debugfs_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static __init int sync_debugfs_init(void) +{ + debugfs_create_file("sync", S_IRUGO, NULL, NULL, &sync_debugfs_fops); + return 0; +} + +late_initcall(sync_debugfs_init); + +#endif |