linux_dsm_epyc7002/drivers/gpu/drm/drm_modeset_lock.c

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/*
* Copyright (C) 2014 Red Hat
* Author: Rob Clark <robdclark@gmail.com>
*
* 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 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
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) 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 <drm/drmP.h>
#include <drm/drm_crtc.h>
#include <drm/drm_modeset_lock.h>
/**
* DOC: kms locking
*
* As KMS moves toward more fine grained locking, and atomic ioctl where
* userspace can indirectly control locking order, it becomes necessary
* to use &ww_mutex and acquire-contexts to avoid deadlocks. But because
* the locking is more distributed around the driver code, we want a bit
* of extra utility/tracking out of our acquire-ctx. This is provided
* by drm_modeset_lock / drm_modeset_acquire_ctx.
*
* For basic principles of &ww_mutex, see: Documentation/locking/ww-mutex-design.txt
*
* The basic usage pattern is to::
*
* drm_modeset_acquire_init(&ctx)
drm/doc: Convert to markdown DRM Docbook is now Markdown ready. This means its doc is able to use markdown text on it. * Documentation/DocBook/drm.tmpl: Contains a table duplicated from drivers/gpu/drm/i915/i915_reg.h. This is not needed anymore * drivers/gpu/drm/drm_modeset_lock.c: had a code example that used to look pretty bad on html. Fixed by using proper code markup. * drivers/gpu/drm/drm_prime.c: Remove spaces between lines to make a proper markup list. * drivers/gpu/drm/i915/i915_reg.h: Altought pandoc supports tables, it doesn't support table cell spanning. But we can use fixed-width for those special cases. * include/drm/drm_vma_manager.h: Another code example that should be proper indented with four spaces. v2 (Daniel): Adjust name to gpu.xml due to rename. v3 (Daniel): Split out the actual enabling in the Makefile - this way we can merge the conversion, while just keeping the enabling in a drm-private tree. Signed-off-by: Danilo Cesar Lemes de Paula <danilo.cesar@collabora.co.uk> (v1) Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Stephan Mueller <smueller@chronox.de> Cc: Michal Marek <mmarek@suse.cz> Cc: linux-kernel@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: intel-gfx <intel-gfx@lists.freedesktop.org> Cc: dri-devel <dri-devel@lists.freedesktop.org> Acked-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1448471279-19748-2-git-send-email-daniel.vetter@ffwll.ch
2015-11-26 00:07:55 +07:00
* retry:
* foreach (lock in random_ordered_set_of_locks) {
drm/doc: Convert to markdown DRM Docbook is now Markdown ready. This means its doc is able to use markdown text on it. * Documentation/DocBook/drm.tmpl: Contains a table duplicated from drivers/gpu/drm/i915/i915_reg.h. This is not needed anymore * drivers/gpu/drm/drm_modeset_lock.c: had a code example that used to look pretty bad on html. Fixed by using proper code markup. * drivers/gpu/drm/drm_prime.c: Remove spaces between lines to make a proper markup list. * drivers/gpu/drm/i915/i915_reg.h: Altought pandoc supports tables, it doesn't support table cell spanning. But we can use fixed-width for those special cases. * include/drm/drm_vma_manager.h: Another code example that should be proper indented with four spaces. v2 (Daniel): Adjust name to gpu.xml due to rename. v3 (Daniel): Split out the actual enabling in the Makefile - this way we can merge the conversion, while just keeping the enabling in a drm-private tree. Signed-off-by: Danilo Cesar Lemes de Paula <danilo.cesar@collabora.co.uk> (v1) Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Stephan Mueller <smueller@chronox.de> Cc: Michal Marek <mmarek@suse.cz> Cc: linux-kernel@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: intel-gfx <intel-gfx@lists.freedesktop.org> Cc: dri-devel <dri-devel@lists.freedesktop.org> Acked-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1448471279-19748-2-git-send-email-daniel.vetter@ffwll.ch
2015-11-26 00:07:55 +07:00
* ret = drm_modeset_lock(lock, &ctx)
* if (ret == -EDEADLK) {
* drm_modeset_backoff(&ctx);
* goto retry;
* }
* }
* ... do stuff ...
* drm_modeset_drop_locks(&ctx);
* drm_modeset_acquire_fini(&ctx);
*
* On top of of these per-object locks using &ww_mutex there's also an overall
* dev->mode_config.lock, for protecting everything else. Mostly this means
* probe state of connectors, and preventing hotplug add/removal of connectors.
*
* Finally there's a bunch of dedicated locks to protect drm core internal
* lists and lookup data structures.
*/
/**
* drm_modeset_lock_all - take all modeset locks
* @dev: DRM device
*
* This function takes all modeset locks, suitable where a more fine-grained
* scheme isn't (yet) implemented. Locks must be dropped by calling the
* drm_modeset_unlock_all() function.
*
* This function is deprecated. It allocates a lock acquisition context and
* stores it in the DRM device's ->mode_config. This facilitate conversion of
* existing code because it removes the need to manually deal with the
* acquisition context, but it is also brittle because the context is global
* and care must be taken not to nest calls. New code should use the
* drm_modeset_lock_all_ctx() function and pass in the context explicitly.
*/
void drm_modeset_lock_all(struct drm_device *dev)
{
struct drm_mode_config *config = &dev->mode_config;
struct drm_modeset_acquire_ctx *ctx;
int ret;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (WARN_ON(!ctx))
return;
mutex_lock(&config->mutex);
drm_modeset_acquire_init(ctx, 0);
retry:
ret = drm_modeset_lock_all_ctx(dev, ctx);
if (ret < 0) {
if (ret == -EDEADLK) {
drm_modeset_backoff(ctx);
goto retry;
}
drm_modeset_acquire_fini(ctx);
kfree(ctx);
return;
}
WARN_ON(config->acquire_ctx);
/*
* We hold the locks now, so it is safe to stash the acquisition
* context for drm_modeset_unlock_all().
*/
config->acquire_ctx = ctx;
drm_warn_on_modeset_not_all_locked(dev);
}
EXPORT_SYMBOL(drm_modeset_lock_all);
/**
* drm_modeset_unlock_all - drop all modeset locks
* @dev: DRM device
*
* This function drops all modeset locks taken by a previous call to the
* drm_modeset_lock_all() function.
*
* This function is deprecated. It uses the lock acquisition context stored
* in the DRM device's ->mode_config. This facilitates conversion of existing
* code because it removes the need to manually deal with the acquisition
* context, but it is also brittle because the context is global and care must
* be taken not to nest calls. New code should pass the acquisition context
* directly to the drm_modeset_drop_locks() function.
*/
void drm_modeset_unlock_all(struct drm_device *dev)
{
struct drm_mode_config *config = &dev->mode_config;
struct drm_modeset_acquire_ctx *ctx = config->acquire_ctx;
if (WARN_ON(!ctx))
return;
config->acquire_ctx = NULL;
drm_modeset_drop_locks(ctx);
drm_modeset_acquire_fini(ctx);
kfree(ctx);
mutex_unlock(&dev->mode_config.mutex);
}
EXPORT_SYMBOL(drm_modeset_unlock_all);
/**
drm: Per-plane locking Turned out to be much simpler on top of my latest atomic stuff than what I've feared. Some details: - Drop the modeset_lock_all snakeoil in drm_plane_init. Same justification as for the equivalent change in drm_crtc_init done in commit d0fa1af40e784aaf7ebb7ba8a17b229bb3fa4c21 Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Mon Sep 8 09:02:49 2014 +0200 drm: Drop modeset locking from crtc init function Without these the drm_modeset_lock_init would fall over the exact same way. - Since the atomic core code wraps the locking switching it to per-plane locks was a one-line change. - For the legacy ioctls add a plane argument to the locking helper so that we can grab the right plane lock (cursor or primary). Since the universal cursor plane might not be there, or someone really crazy might forgoe the primary plane even accept NULL. - Add some locking WARN_ON to the atomic helpers for good paranoid measure and to check that it all works out. Tested on my exynos atomic hackfest with full lockdep checks and ww backoff injection. v2: I've forgotten about the load-detect code in i915. v3: Thierry reported that in latest 3.18-rc vmwgfx doesn't compile any more due to commit 21e88620aa21b48d4f62d29275e3e2944a5ea2b5 Author: Rob Clark <robdclark@gmail.com> Date: Thu Oct 30 13:39:04 2014 -0400 drm/vmwgfx: fix lock breakage Rebased and fix this up. Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-11-11 16:12:00 +07:00
* drm_modeset_lock_crtc - lock crtc with hidden acquire ctx for a plane update
* @crtc: DRM CRTC
* @plane: DRM plane to be updated on @crtc
*
* This function locks the given crtc and plane (which should be either the
* primary or cursor plane) using a hidden acquire context. This is necessary so
* that drivers internally using the atomic interfaces can grab further locks
* with the lock acquire context.
*
drm: Per-plane locking Turned out to be much simpler on top of my latest atomic stuff than what I've feared. Some details: - Drop the modeset_lock_all snakeoil in drm_plane_init. Same justification as for the equivalent change in drm_crtc_init done in commit d0fa1af40e784aaf7ebb7ba8a17b229bb3fa4c21 Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Mon Sep 8 09:02:49 2014 +0200 drm: Drop modeset locking from crtc init function Without these the drm_modeset_lock_init would fall over the exact same way. - Since the atomic core code wraps the locking switching it to per-plane locks was a one-line change. - For the legacy ioctls add a plane argument to the locking helper so that we can grab the right plane lock (cursor or primary). Since the universal cursor plane might not be there, or someone really crazy might forgoe the primary plane even accept NULL. - Add some locking WARN_ON to the atomic helpers for good paranoid measure and to check that it all works out. Tested on my exynos atomic hackfest with full lockdep checks and ww backoff injection. v2: I've forgotten about the load-detect code in i915. v3: Thierry reported that in latest 3.18-rc vmwgfx doesn't compile any more due to commit 21e88620aa21b48d4f62d29275e3e2944a5ea2b5 Author: Rob Clark <robdclark@gmail.com> Date: Thu Oct 30 13:39:04 2014 -0400 drm/vmwgfx: fix lock breakage Rebased and fix this up. Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-11-11 16:12:00 +07:00
* Note that @plane can be NULL, e.g. when the cursor support hasn't yet been
* converted to universal planes yet.
*/
drm: Per-plane locking Turned out to be much simpler on top of my latest atomic stuff than what I've feared. Some details: - Drop the modeset_lock_all snakeoil in drm_plane_init. Same justification as for the equivalent change in drm_crtc_init done in commit d0fa1af40e784aaf7ebb7ba8a17b229bb3fa4c21 Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Mon Sep 8 09:02:49 2014 +0200 drm: Drop modeset locking from crtc init function Without these the drm_modeset_lock_init would fall over the exact same way. - Since the atomic core code wraps the locking switching it to per-plane locks was a one-line change. - For the legacy ioctls add a plane argument to the locking helper so that we can grab the right plane lock (cursor or primary). Since the universal cursor plane might not be there, or someone really crazy might forgoe the primary plane even accept NULL. - Add some locking WARN_ON to the atomic helpers for good paranoid measure and to check that it all works out. Tested on my exynos atomic hackfest with full lockdep checks and ww backoff injection. v2: I've forgotten about the load-detect code in i915. v3: Thierry reported that in latest 3.18-rc vmwgfx doesn't compile any more due to commit 21e88620aa21b48d4f62d29275e3e2944a5ea2b5 Author: Rob Clark <robdclark@gmail.com> Date: Thu Oct 30 13:39:04 2014 -0400 drm/vmwgfx: fix lock breakage Rebased and fix this up. Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-11-11 16:12:00 +07:00
void drm_modeset_lock_crtc(struct drm_crtc *crtc,
struct drm_plane *plane)
{
struct drm_modeset_acquire_ctx *ctx;
int ret;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (WARN_ON(!ctx))
return;
drm_modeset_acquire_init(ctx, 0);
retry:
ret = drm_modeset_lock(&crtc->mutex, ctx);
if (ret)
goto fail;
drm: Per-plane locking Turned out to be much simpler on top of my latest atomic stuff than what I've feared. Some details: - Drop the modeset_lock_all snakeoil in drm_plane_init. Same justification as for the equivalent change in drm_crtc_init done in commit d0fa1af40e784aaf7ebb7ba8a17b229bb3fa4c21 Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Mon Sep 8 09:02:49 2014 +0200 drm: Drop modeset locking from crtc init function Without these the drm_modeset_lock_init would fall over the exact same way. - Since the atomic core code wraps the locking switching it to per-plane locks was a one-line change. - For the legacy ioctls add a plane argument to the locking helper so that we can grab the right plane lock (cursor or primary). Since the universal cursor plane might not be there, or someone really crazy might forgoe the primary plane even accept NULL. - Add some locking WARN_ON to the atomic helpers for good paranoid measure and to check that it all works out. Tested on my exynos atomic hackfest with full lockdep checks and ww backoff injection. v2: I've forgotten about the load-detect code in i915. v3: Thierry reported that in latest 3.18-rc vmwgfx doesn't compile any more due to commit 21e88620aa21b48d4f62d29275e3e2944a5ea2b5 Author: Rob Clark <robdclark@gmail.com> Date: Thu Oct 30 13:39:04 2014 -0400 drm/vmwgfx: fix lock breakage Rebased and fix this up. Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-11-11 16:12:00 +07:00
if (plane) {
ret = drm_modeset_lock(&plane->mutex, ctx);
if (ret)
goto fail;
if (plane->crtc) {
ret = drm_modeset_lock(&plane->crtc->mutex, ctx);
if (ret)
goto fail;
}
}
WARN_ON(crtc->acquire_ctx);
/* now we hold the locks, so now that it is safe, stash the
* ctx for drm_modeset_unlock_crtc():
*/
crtc->acquire_ctx = ctx;
return;
fail:
if (ret == -EDEADLK) {
drm_modeset_backoff(ctx);
goto retry;
}
}
EXPORT_SYMBOL(drm_modeset_lock_crtc);
/**
* drm_modeset_legacy_acquire_ctx - find acquire ctx for legacy ioctls
* @crtc: drm crtc
*
* Legacy ioctl operations like cursor updates or page flips only have per-crtc
* locking, and store the acquire ctx in the corresponding crtc. All other
* legacy operations take all locks and use a global acquire context. This
* function grabs the right one.
*/
struct drm_modeset_acquire_ctx *
drm_modeset_legacy_acquire_ctx(struct drm_crtc *crtc)
{
if (crtc->acquire_ctx)
return crtc->acquire_ctx;
WARN_ON(!crtc->dev->mode_config.acquire_ctx);
return crtc->dev->mode_config.acquire_ctx;
}
EXPORT_SYMBOL(drm_modeset_legacy_acquire_ctx);
/**
* drm_modeset_unlock_crtc - drop crtc lock
* @crtc: drm crtc
*
* This drops the crtc lock acquire with drm_modeset_lock_crtc() and all other
* locks acquired through the hidden context.
*/
void drm_modeset_unlock_crtc(struct drm_crtc *crtc)
{
struct drm_modeset_acquire_ctx *ctx = crtc->acquire_ctx;
if (WARN_ON(!ctx))
return;
crtc->acquire_ctx = NULL;
drm_modeset_drop_locks(ctx);
drm_modeset_acquire_fini(ctx);
kfree(ctx);
}
EXPORT_SYMBOL(drm_modeset_unlock_crtc);
/**
* drm_warn_on_modeset_not_all_locked - check that all modeset locks are locked
* @dev: device
*
* Useful as a debug assert.
*/
void drm_warn_on_modeset_not_all_locked(struct drm_device *dev)
{
struct drm_crtc *crtc;
/* Locking is currently fubar in the panic handler. */
if (oops_in_progress)
return;
drm_for_each_crtc(crtc, dev)
WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
}
EXPORT_SYMBOL(drm_warn_on_modeset_not_all_locked);
/**
* drm_modeset_acquire_init - initialize acquire context
* @ctx: the acquire context
* @flags: for future
*/
void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx,
uint32_t flags)
{
memset(ctx, 0, sizeof(*ctx));
ww_acquire_init(&ctx->ww_ctx, &crtc_ww_class);
INIT_LIST_HEAD(&ctx->locked);
}
EXPORT_SYMBOL(drm_modeset_acquire_init);
/**
* drm_modeset_acquire_fini - cleanup acquire context
* @ctx: the acquire context
*/
void drm_modeset_acquire_fini(struct drm_modeset_acquire_ctx *ctx)
{
ww_acquire_fini(&ctx->ww_ctx);
}
EXPORT_SYMBOL(drm_modeset_acquire_fini);
/**
* drm_modeset_drop_locks - drop all locks
* @ctx: the acquire context
*
* Drop all locks currently held against this acquire context.
*/
void drm_modeset_drop_locks(struct drm_modeset_acquire_ctx *ctx)
{
WARN_ON(ctx->contended);
while (!list_empty(&ctx->locked)) {
struct drm_modeset_lock *lock;
lock = list_first_entry(&ctx->locked,
struct drm_modeset_lock, head);
drm_modeset_unlock(lock);
}
}
EXPORT_SYMBOL(drm_modeset_drop_locks);
static inline int modeset_lock(struct drm_modeset_lock *lock,
struct drm_modeset_acquire_ctx *ctx,
bool interruptible, bool slow)
{
int ret;
WARN_ON(ctx->contended);
if (ctx->trylock_only) {
lockdep_assert_held(&ctx->ww_ctx);
if (!ww_mutex_trylock(&lock->mutex))
return -EBUSY;
else
return 0;
} else if (interruptible && slow) {
ret = ww_mutex_lock_slow_interruptible(&lock->mutex, &ctx->ww_ctx);
} else if (interruptible) {
ret = ww_mutex_lock_interruptible(&lock->mutex, &ctx->ww_ctx);
} else if (slow) {
ww_mutex_lock_slow(&lock->mutex, &ctx->ww_ctx);
ret = 0;
} else {
ret = ww_mutex_lock(&lock->mutex, &ctx->ww_ctx);
}
if (!ret) {
WARN_ON(!list_empty(&lock->head));
list_add(&lock->head, &ctx->locked);
} else if (ret == -EALREADY) {
/* we already hold the lock.. this is fine. For atomic
* we will need to be able to drm_modeset_lock() things
* without having to keep track of what is already locked
* or not.
*/
ret = 0;
} else if (ret == -EDEADLK) {
ctx->contended = lock;
}
return ret;
}
static int modeset_backoff(struct drm_modeset_acquire_ctx *ctx,
bool interruptible)
{
struct drm_modeset_lock *contended = ctx->contended;
ctx->contended = NULL;
if (WARN_ON(!contended))
return 0;
drm_modeset_drop_locks(ctx);
return modeset_lock(contended, ctx, interruptible, true);
}
/**
* drm_modeset_backoff - deadlock avoidance backoff
* @ctx: the acquire context
*
* If deadlock is detected (ie. drm_modeset_lock() returns -EDEADLK),
* you must call this function to drop all currently held locks and
* block until the contended lock becomes available.
*/
void drm_modeset_backoff(struct drm_modeset_acquire_ctx *ctx)
{
modeset_backoff(ctx, false);
}
EXPORT_SYMBOL(drm_modeset_backoff);
/**
* drm_modeset_backoff_interruptible - deadlock avoidance backoff
* @ctx: the acquire context
*
* Interruptible version of drm_modeset_backoff()
*/
int drm_modeset_backoff_interruptible(struct drm_modeset_acquire_ctx *ctx)
{
return modeset_backoff(ctx, true);
}
EXPORT_SYMBOL(drm_modeset_backoff_interruptible);
/**
* drm_modeset_lock - take modeset lock
* @lock: lock to take
* @ctx: acquire ctx
*
* If ctx is not NULL, then its ww acquire context is used and the
* lock will be tracked by the context and can be released by calling
* drm_modeset_drop_locks(). If -EDEADLK is returned, this means a
* deadlock scenario has been detected and it is an error to attempt
* to take any more locks without first calling drm_modeset_backoff().
*/
int drm_modeset_lock(struct drm_modeset_lock *lock,
struct drm_modeset_acquire_ctx *ctx)
{
if (ctx)
return modeset_lock(lock, ctx, false, false);
ww_mutex_lock(&lock->mutex, NULL);
return 0;
}
EXPORT_SYMBOL(drm_modeset_lock);
/**
* drm_modeset_lock_interruptible - take modeset lock
* @lock: lock to take
* @ctx: acquire ctx
*
* Interruptible version of drm_modeset_lock()
*/
int drm_modeset_lock_interruptible(struct drm_modeset_lock *lock,
struct drm_modeset_acquire_ctx *ctx)
{
if (ctx)
return modeset_lock(lock, ctx, true, false);
return ww_mutex_lock_interruptible(&lock->mutex, NULL);
}
EXPORT_SYMBOL(drm_modeset_lock_interruptible);
/**
* drm_modeset_unlock - drop modeset lock
* @lock: lock to release
*/
void drm_modeset_unlock(struct drm_modeset_lock *lock)
{
list_del_init(&lock->head);
ww_mutex_unlock(&lock->mutex);
}
EXPORT_SYMBOL(drm_modeset_unlock);
/**
* drm_modeset_lock_all_ctx - take all modeset locks
* @dev: DRM device
* @ctx: lock acquisition context
*
* This function takes all modeset locks, suitable where a more fine-grained
* scheme isn't (yet) implemented.
*
* Unlike drm_modeset_lock_all(), it doesn't take the dev->mode_config.mutex
* since that lock isn't required for modeset state changes. Callers which
* need to grab that lock too need to do so outside of the acquire context
* @ctx.
*
* Locks acquired with this function should be released by calling the
* drm_modeset_drop_locks() function on @ctx.
*
* Returns: 0 on success or a negative error-code on failure.
*/
int drm_modeset_lock_all_ctx(struct drm_device *dev,
struct drm_modeset_acquire_ctx *ctx)
{
struct drm_crtc *crtc;
drm: Per-plane locking Turned out to be much simpler on top of my latest atomic stuff than what I've feared. Some details: - Drop the modeset_lock_all snakeoil in drm_plane_init. Same justification as for the equivalent change in drm_crtc_init done in commit d0fa1af40e784aaf7ebb7ba8a17b229bb3fa4c21 Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Mon Sep 8 09:02:49 2014 +0200 drm: Drop modeset locking from crtc init function Without these the drm_modeset_lock_init would fall over the exact same way. - Since the atomic core code wraps the locking switching it to per-plane locks was a one-line change. - For the legacy ioctls add a plane argument to the locking helper so that we can grab the right plane lock (cursor or primary). Since the universal cursor plane might not be there, or someone really crazy might forgoe the primary plane even accept NULL. - Add some locking WARN_ON to the atomic helpers for good paranoid measure and to check that it all works out. Tested on my exynos atomic hackfest with full lockdep checks and ww backoff injection. v2: I've forgotten about the load-detect code in i915. v3: Thierry reported that in latest 3.18-rc vmwgfx doesn't compile any more due to commit 21e88620aa21b48d4f62d29275e3e2944a5ea2b5 Author: Rob Clark <robdclark@gmail.com> Date: Thu Oct 30 13:39:04 2014 -0400 drm/vmwgfx: fix lock breakage Rebased and fix this up. Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-11-11 16:12:00 +07:00
struct drm_plane *plane;
int ret;
ret = drm_modeset_lock(&dev->mode_config.connection_mutex, ctx);
if (ret)
return ret;
drm_for_each_crtc(crtc, dev) {
ret = drm_modeset_lock(&crtc->mutex, ctx);
if (ret)
return ret;
}
drm_for_each_plane(plane, dev) {
drm: Per-plane locking Turned out to be much simpler on top of my latest atomic stuff than what I've feared. Some details: - Drop the modeset_lock_all snakeoil in drm_plane_init. Same justification as for the equivalent change in drm_crtc_init done in commit d0fa1af40e784aaf7ebb7ba8a17b229bb3fa4c21 Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Mon Sep 8 09:02:49 2014 +0200 drm: Drop modeset locking from crtc init function Without these the drm_modeset_lock_init would fall over the exact same way. - Since the atomic core code wraps the locking switching it to per-plane locks was a one-line change. - For the legacy ioctls add a plane argument to the locking helper so that we can grab the right plane lock (cursor or primary). Since the universal cursor plane might not be there, or someone really crazy might forgoe the primary plane even accept NULL. - Add some locking WARN_ON to the atomic helpers for good paranoid measure and to check that it all works out. Tested on my exynos atomic hackfest with full lockdep checks and ww backoff injection. v2: I've forgotten about the load-detect code in i915. v3: Thierry reported that in latest 3.18-rc vmwgfx doesn't compile any more due to commit 21e88620aa21b48d4f62d29275e3e2944a5ea2b5 Author: Rob Clark <robdclark@gmail.com> Date: Thu Oct 30 13:39:04 2014 -0400 drm/vmwgfx: fix lock breakage Rebased and fix this up. Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-11-11 16:12:00 +07:00
ret = drm_modeset_lock(&plane->mutex, ctx);
if (ret)
return ret;
}
return 0;
}
EXPORT_SYMBOL(drm_modeset_lock_all_ctx);