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path: root/drivers/char/drm/drm_lock.c
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2008-07-14drm: reorganise drm tree to be more future proof.Dave Airlie
With the coming of kernel based modesetting and the memory manager stuff, the everything in one directory approach was getting very ugly and starting to be unmanageable. This restructures the drm along the lines of other kernel components. It creates a drivers/gpu/drm directory and moves the hw drivers into subdirectores. It moves the includes into an include/drm, and sets up the unifdef for the userspace headers we should be exporting. Signed-off-by: Dave Airlie <airlied@redhat.com>
2008-05-07drm: disable tasklets not IRQs when taking the drm lock spinlockThomas Hellstrom
Signed-off-by: Dave Airlie <airlied@redhat.com>
2008-03-17drm: Fix race that can lockup the kernelMike Isely
The i915_vblank_swap() function schedules an automatic buffer swap upon receipt of the vertical sync interrupt. Such an operation is lengthy so it can't be allowed to happen in normal interrupt context, thus the DRM implements this by scheduling the work in a kernel softirq-scheduled tasklet. In order for the buffer swap to work safely, the DRM's central lock must be taken, via a call to drm_lock_take() located in drivers/char/drm/drm_irq.c within the function drm_locked_tasklet_func(). The lock-taking logic uses a non-interrupt-blocking spinlock to implement the manipulations needed to take the lock. This semantic would be safe if all attempts to use the spinlock only happen from process context. However this buffer swap happens from softirq context which is really a form of interrupt context. Thus we have an unsafe situation, in that drm_locked_tasklet_func() can block on a spinlock already taken by a thread in process context which will never get scheduled again because of the blocked softirq tasklet. This wedges the kernel hard. To trigger this bug, run a dual-head cloned mode configuration which uses the i915 drm, then execute an opengl application which synchronizes buffer swaps against the vertical sync interrupt. In my testing, a lockup always results after running anywhere from 5 minutes to an hour and a half. I believe dual-head is needed to really trigger the problem because then the vertical sync interrupt handling is no longer predictable (due to being interrupt-sourced from two different heads running at different speeds). This raises the probability of the tasklet trying to run while the userspace DRI is doing things to the GPU (and manipulating the DRM lock). The fix is to change the relevant spinlock semantics to be the interrupt-blocking form. After this change I am no longer able to trigger the lockup; the longest test run so far was 20 hours (test stopped after that point). Note: I have examined the places where this spinlock is being employed; all are reasonably short bounded sequences and should be suitable for interrupts being blocked without impacting overall kernel interrupt response latency. Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2007-10-19Use helpers to obtain task pid in printksPavel Emelyanov
The task_struct->pid member is going to be deprecated, so start using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in the kernel. The first thing to start with is the pid, printed to dmesg - in this case we may safely use task_pid_nr(). Besides, printks produce more (much more) than a half of all the explicit pid usage. [akpm@linux-foundation.org: git-drm went and changed lots of stuff] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Dave Airlie <airlied@linux.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-15drm: Replace DRM_IOCTL_ARGS with (dev, data, file_priv) and remove DRM_DEVICE.Eric Anholt
The data is now in kernel space, copied in/out as appropriate according to t This results in DRM_COPY_{TO,FROM}_USER going away, and error paths to deal with those failures. This also means that XFree86 4.2.0 support for i810 DR is lost. Signed-off-by: Dave Airlie <airlied@linux.ie>
2007-10-15drm: Replace filp in ioctl arguments with drm_file *file_priv.Eric Anholt
As a fallout, replace filp storage with file_priv storage for "unique identifier of a client" all over the DRM. There is a 1:1 mapping, so this should be a noop. This could be a minor performance improvement, as everyth on Linux dereferenced filp to get file_priv anyway, while only the mmap ioct went the other direction. Signed-off-by: Dave Airlie <airlied@linux.ie>
2007-10-15drm: Remove DRM_ERR OS macro.Eric Anholt
This was used to make all ioctl handlers return -errno on linux and errno on *BSD. Instead, just return -errno in shared code, and flip sign on return f shared code to *BSD code. Signed-off-by: Dave Airlie <airlied@linux.ie>
2007-07-11drm: detypedeffing continues...Dave Airlie
Signed-off-by: Dave Airlie <airlied@linux.ie>
2007-07-11drm: remove drm_file_t, drm_device_t and drm_head_t typedefsDave Airlie
some drivers still todo. Signed-off-by: Dave Airlie <airlied@linux.ie>
2007-07-11drm: remove a bunch of typedefs on the userspace interfaceDave Airlie
This moves a bunch of typedefs into a !defined __KERNEL__ to keep userspace API compatiblity, it changes all internal usages to structs/enum/unions. Signed-off-by: Dave Airlie <airlied@linux.ie>
2007-03-23drm: fix driver deadlock with AIGLX and reclaim_buffers_lockedThomas Hellstrom
Bugzilla Bug #9457 Add refcounting of user waiters to the DRM hardware lock, so that we can use DRM_LOCK_CONT flag more conservatively. Also add a kernel waiter refcount that if nonzero transfers the lock for the kernel context when it is released. This is useful when waiting for idle and can be used for very simple fence object driver implementations for the new memory manager Signed-off-by: Dave Airlie <airlied@linux.ie>
2006-12-19drm: make kernel context switch same as for drm git tree.Dave Airlie
Signed-off-by: Dave Airlie <airlied@linux.ie>
2006-12-07drm: fix up irqflags in drm_lock.cDave Airlie
Signed-off-by: Dave Airlie <airlied@linux.ie>
2006-12-07drm: Add support for interrupt triggered driver callback with lock held to ↵=?utf-8?q?Michel_D=C3=A4nzer?=
DRM core. Signed-off-by: Dave Airlie <airlied@linux.ie>
2006-01-03drm: merge in Linus mainlineDave Airlie
2006-01-02drm: major update from CVS for radeon and coreDave Airlie
This patch pull in a lot of changes from CVS to the main core DRM, and updates the radeon driver to 1.21.0 that supports r300 texrect and radeon card type ioctl. Signed-off-by: Dave Airlie <airlied@linux.ie>
2005-11-24drm: fix quiescent lockingDave Airlie
A fix for a locking bug which is triggered when a client tries to lock with flag DMA_QUIESCENT (typically the X server), but gets interrupted by a signal. The locking IOCTL should then return an error, but if DMA_QUIESCENT succeeds it returns 0, and the client falsely thinks it has the lock. In addition The client waits for DMA_QUISCENT and possibly DMA_READY without having the lock. From: Thomas Hellstrom Signed-off-by: Dave Airlie <airlied@linux.ie>
2005-09-25drm: lindent the drm directory.Dave Airlie
I've been threatening this for a while, so no point hanging around. This lindents the DRM code which was always really bad in tabbing department. I've also fixed some misnamed files in comments and removed some trailing whitespace. Signed-off-by: Dave Airlie <airlied@linux.ie>
2005-07-07drm: misc cleanupDave Airlie
This patch contains the following cleanups: - make needlessly global functions static - remove the following unused global functions: - drm_fops.c: drm_read - i915_dma.c: i915_do_cleanup_pageflip Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Dave Airlie <airlied@linux.ie>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!