Author | Tokens | Token Proportion | Commits | Commit Proportion |
---|---|---|---|---|
Daniel Vetter | 466 | 32.84% | 11 | 20.37% |
Thomas Hellstrom | 305 | 21.49% | 4 | 7.41% |
Linus Torvalds (pre-git) | 276 | 19.45% | 5 | 9.26% |
Dave Airlie | 262 | 18.46% | 18 | 33.33% |
Eric Anholt | 39 | 2.75% | 2 | 3.70% |
David Herrmann | 16 | 1.13% | 2 | 3.70% |
Arnd Bergmann | 13 | 0.92% | 1 | 1.85% |
Chris Wilson | 11 | 0.78% | 2 | 3.70% |
Linus Torvalds | 7 | 0.49% | 2 | 3.70% |
Pavel Emelyanov | 6 | 0.42% | 1 | 1.85% |
Benjamin Gaignard | 5 | 0.35% | 1 | 1.85% |
Michel Dänzer | 4 | 0.28% | 1 | 1.85% |
Ingo Molnar | 3 | 0.21% | 1 | 1.85% |
Sam Ravnborg | 3 | 0.21% | 1 | 1.85% |
Paul Gortmaker | 2 | 0.14% | 1 | 1.85% |
Qian Cai | 1 | 0.07% | 1 | 1.85% |
Total | 1419 | 54 |
/* * \file drm_lock.c * IOCTLs for locking * * \author Rickard E. (Rik) Faith <faith@valinux.com> * \author Gareth Hughes <gareth@valinux.com> */ /* * Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com * * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas. * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. */ #include <linux/export.h> #include <linux/sched/signal.h> #include <drm/drm.h> #include <drm/drm_drv.h> #include <drm/drm_file.h> #include <drm/drm_print.h> #include "drm_internal.h" #include "drm_legacy.h" static int drm_lock_take(struct drm_lock_data *lock_data, unsigned int context); /* * Take the heavyweight lock. * * \param lock lock pointer. * \param context locking context. * \return one if the lock is held, or zero otherwise. * * Attempt to mark the lock as held by the given context, via the \p cmpxchg instruction. */ static int drm_lock_take(struct drm_lock_data *lock_data, unsigned int context) { unsigned int old, new, prev; volatile unsigned int *lock = &lock_data->hw_lock->lock; spin_lock_bh(&lock_data->spinlock); do { old = *lock; if (old & _DRM_LOCK_HELD) new = old | _DRM_LOCK_CONT; else { new = context | _DRM_LOCK_HELD | ((lock_data->user_waiters + lock_data->kernel_waiters > 1) ? _DRM_LOCK_CONT : 0); } prev = cmpxchg(lock, old, new); } while (prev != old); spin_unlock_bh(&lock_data->spinlock); if (_DRM_LOCKING_CONTEXT(old) == context) { if (old & _DRM_LOCK_HELD) { if (context != DRM_KERNEL_CONTEXT) { DRM_ERROR("%d holds heavyweight lock\n", context); } return 0; } } if ((_DRM_LOCKING_CONTEXT(new)) == context && (new & _DRM_LOCK_HELD)) { /* Have lock */ return 1; } return 0; } /* * This takes a lock forcibly and hands it to context. Should ONLY be used * inside *_unlock to give lock to kernel before calling *_dma_schedule. * * \param dev DRM device. * \param lock lock pointer. * \param context locking context. * \return always one. * * Resets the lock file pointer. * Marks the lock as held by the given context, via the \p cmpxchg instruction. */ static int drm_lock_transfer(struct drm_lock_data *lock_data, unsigned int context) { unsigned int old, new, prev; volatile unsigned int *lock = &lock_data->hw_lock->lock; lock_data->file_priv = NULL; do { old = *lock; new = context | _DRM_LOCK_HELD; prev = cmpxchg(lock, old, new); } while (prev != old); return 1; } static int drm_legacy_lock_free(struct drm_lock_data *lock_data, unsigned int context) { unsigned int old, new, prev; volatile unsigned int *lock = &lock_data->hw_lock->lock; spin_lock_bh(&lock_data->spinlock); if (lock_data->kernel_waiters != 0) { drm_lock_transfer(lock_data, 0); lock_data->idle_has_lock = 1; spin_unlock_bh(&lock_data->spinlock); return 1; } spin_unlock_bh(&lock_data->spinlock); do { old = *lock; new = _DRM_LOCKING_CONTEXT(old); prev = cmpxchg(lock, old, new); } while (prev != old); if (_DRM_LOCK_IS_HELD(old) && _DRM_LOCKING_CONTEXT(old) != context) { DRM_ERROR("%d freed heavyweight lock held by %d\n", context, _DRM_LOCKING_CONTEXT(old)); return 1; } wake_up_interruptible(&lock_data->lock_queue); return 0; } /* * Lock ioctl. * * \param inode device inode. * \param file_priv DRM file private. * \param cmd command. * \param arg user argument, pointing to a drm_lock structure. * \return zero on success or negative number on failure. * * Add the current task to the lock wait queue, and attempt to take to lock. */ int drm_legacy_lock(struct drm_device *dev, void *data, struct drm_file *file_priv) { DECLARE_WAITQUEUE(entry, current); struct drm_lock *lock = data; struct drm_master *master = file_priv->master; int ret = 0; if (!drm_core_check_feature(dev, DRIVER_LEGACY)) return -EOPNOTSUPP; ++file_priv->lock_count; if (lock->context == DRM_KERNEL_CONTEXT) { DRM_ERROR("Process %d using kernel context %d\n", task_pid_nr(current), lock->context); return -EINVAL; } DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n", lock->context, task_pid_nr(current), master->lock.hw_lock ? master->lock.hw_lock->lock : -1, lock->flags); add_wait_queue(&master->lock.lock_queue, &entry); spin_lock_bh(&master->lock.spinlock); master->lock.user_waiters++; spin_unlock_bh(&master->lock.spinlock); for (;;) { __set_current_state(TASK_INTERRUPTIBLE); if (!master->lock.hw_lock) { /* Device has been unregistered */ send_sig(SIGTERM, current, 0); ret = -EINTR; break; } if (drm_lock_take(&master->lock, lock->context)) { master->lock.file_priv = file_priv; master->lock.lock_time = jiffies; break; /* Got lock */ } /* Contention */ mutex_unlock(&drm_global_mutex); schedule(); mutex_lock(&drm_global_mutex); if (signal_pending(current)) { ret = -EINTR; break; } } spin_lock_bh(&master->lock.spinlock); master->lock.user_waiters--; spin_unlock_bh(&master->lock.spinlock); __set_current_state(TASK_RUNNING); remove_wait_queue(&master->lock.lock_queue, &entry); DRM_DEBUG("%d %s\n", lock->context, ret ? "interrupted" : "has lock"); if (ret) return ret; /* don't set the block all signals on the master process for now * really probably not the correct answer but lets us debug xkb * xserver for now */ if (!drm_is_current_master(file_priv)) { dev->sigdata.context = lock->context; dev->sigdata.lock = master->lock.hw_lock; } if (dev->driver->dma_quiescent && (lock->flags & _DRM_LOCK_QUIESCENT)) { if (dev->driver->dma_quiescent(dev)) { DRM_DEBUG("%d waiting for DMA quiescent\n", lock->context); return -EBUSY; } } return 0; } /* * Unlock ioctl. * * \param inode device inode. * \param file_priv DRM file private. * \param cmd command. * \param arg user argument, pointing to a drm_lock structure. * \return zero on success or negative number on failure. * * Transfer and free the lock. */ int drm_legacy_unlock(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_lock *lock = data; struct drm_master *master = file_priv->master; if (!drm_core_check_feature(dev, DRIVER_LEGACY)) return -EOPNOTSUPP; if (lock->context == DRM_KERNEL_CONTEXT) { DRM_ERROR("Process %d using kernel context %d\n", task_pid_nr(current), lock->context); return -EINVAL; } if (drm_legacy_lock_free(&master->lock, lock->context)) { /* FIXME: Should really bail out here. */ } return 0; } /* * This function returns immediately and takes the hw lock * with the kernel context if it is free, otherwise it gets the highest priority when and if * it is eventually released. * * This guarantees that the kernel will _eventually_ have the lock _unless_ it is held * by a blocked process. (In the latter case an explicit wait for the hardware lock would cause * a deadlock, which is why the "idlelock" was invented). * * This should be sufficient to wait for GPU idle without * having to worry about starvation. */ void drm_legacy_idlelock_take(struct drm_lock_data *lock_data) { int ret; spin_lock_bh(&lock_data->spinlock); lock_data->kernel_waiters++; if (!lock_data->idle_has_lock) { spin_unlock_bh(&lock_data->spinlock); ret = drm_lock_take(lock_data, DRM_KERNEL_CONTEXT); spin_lock_bh(&lock_data->spinlock); if (ret == 1) lock_data->idle_has_lock = 1; } spin_unlock_bh(&lock_data->spinlock); } EXPORT_SYMBOL(drm_legacy_idlelock_take); void drm_legacy_idlelock_release(struct drm_lock_data *lock_data) { unsigned int old, prev; volatile unsigned int *lock = &lock_data->hw_lock->lock; spin_lock_bh(&lock_data->spinlock); if (--lock_data->kernel_waiters == 0) { if (lock_data->idle_has_lock) { do { old = *lock; prev = cmpxchg(lock, old, DRM_KERNEL_CONTEXT); } while (prev != old); wake_up_interruptible(&lock_data->lock_queue); lock_data->idle_has_lock = 0; } } spin_unlock_bh(&lock_data->spinlock); } EXPORT_SYMBOL(drm_legacy_idlelock_release); static int drm_legacy_i_have_hw_lock(struct drm_device *dev, struct drm_file *file_priv) { struct drm_master *master = file_priv->master; return (file_priv->lock_count && master->lock.hw_lock && _DRM_LOCK_IS_HELD(master->lock.hw_lock->lock) && master->lock.file_priv == file_priv); } void drm_legacy_lock_release(struct drm_device *dev, struct file *filp) { struct drm_file *file_priv = filp->private_data; /* if the master has gone away we can't do anything with the lock */ if (!dev->master) return; if (drm_legacy_i_have_hw_lock(dev, file_priv)) { DRM_DEBUG("File %p released, freeing lock for context %d\n", filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); drm_legacy_lock_free(&file_priv->master->lock, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); } } void drm_legacy_lock_master_cleanup(struct drm_device *dev, struct drm_master *master) { if (!drm_core_check_feature(dev, DRIVER_LEGACY)) return; /* * Since the master is disappearing, so is the * possibility to lock. */ mutex_lock(&dev->struct_mutex); if (master->lock.hw_lock) { if (dev->sigdata.lock == master->lock.hw_lock) dev->sigdata.lock = NULL; master->lock.hw_lock = NULL; master->lock.file_priv = NULL; wake_up_interruptible_all(&master->lock.lock_queue); } mutex_unlock(&dev->struct_mutex); }
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