From patchwork Wed May 8 12:05:42 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10935545 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E1AFF92A for ; Wed, 8 May 2019 12:06:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CD256286D3 for ; Wed, 8 May 2019 12:06:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C055E28715; Wed, 8 May 2019 12:06:00 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 6014C286D3 for ; Wed, 8 May 2019 12:05:59 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2A884896B5; Wed, 8 May 2019 12:05:57 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id 709F889622 for ; Wed, 8 May 2019 12:05:54 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 16489690-1500050 for multiple; Wed, 08 May 2019 13:05:51 +0100 From: Chris Wilson To: dri-devel@lists.freedesktop.org Subject: [PATCH 2/2] dma-fence: Refactor signaling for manual invocation Date: Wed, 8 May 2019 13:05:42 +0100 Message-Id: <20190508120542.28377-3-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190508120542.28377-1-chris@chris-wilson.co.uk> References: <20190508120542.28377-1-chris@chris-wilson.co.uk> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tvrtko Ursulin Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP Move the duplicated code within dma-fence.c into the header for wider reuse. In the process apply a small micro-optimisation to only prune the fence->cb_list once rather than use list_del on every entry. Signed-off-by: Chris Wilson Reviewed-by: Tvrtko Ursulin --- drivers/dma-buf/Makefile | 10 +- drivers/dma-buf/dma-fence-trace.c | 28 +++ drivers/dma-buf/dma-fence.c | 32 +-- drivers/gpu/drm/i915/gt/intel_breadcrumbs.c | 30 --- include/linux/dma-fence-types.h | 248 +++++++++++++++++++ include/linux/dma-fence.h | 251 +++----------------- 6 files changed, 321 insertions(+), 278 deletions(-) create mode 100644 drivers/dma-buf/dma-fence-trace.c create mode 100644 include/linux/dma-fence-types.h diff --git a/drivers/dma-buf/Makefile b/drivers/dma-buf/Makefile index 1f006e083eb9..56e579878f26 100644 --- a/drivers/dma-buf/Makefile +++ b/drivers/dma-buf/Makefile @@ -1,5 +1,11 @@ -obj-y := dma-buf.o dma-fence.o dma-fence-array.o dma-fence-chain.o \ - reservation.o seqno-fence.o +obj-y := \ + dma-buf.o \ + dma-fence.o \ + dma-fence-array.o \ + dma-fence-chain.o \ + dma-fence-trace.o \ + reservation.o \ + seqno-fence.o obj-$(CONFIG_SYNC_FILE) += sync_file.o obj-$(CONFIG_SW_SYNC) += sw_sync.o sync_debug.o obj-$(CONFIG_UDMABUF) += udmabuf.o diff --git a/drivers/dma-buf/dma-fence-trace.c b/drivers/dma-buf/dma-fence-trace.c new file mode 100644 index 000000000000..eb6f282be4c0 --- /dev/null +++ b/drivers/dma-buf/dma-fence-trace.c @@ -0,0 +1,28 @@ +/* + * Fence mechanism for dma-buf and to allow for asynchronous dma access + * + * Copyright (C) 2012 Canonical Ltd + * Copyright (C) 2012 Texas Instruments + * + * Authors: + * Rob Clark + * Maarten Lankhorst + * + * 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. + */ + +#include + +#define CREATE_TRACE_POINTS +#include + +EXPORT_TRACEPOINT_SYMBOL(dma_fence_emit); +EXPORT_TRACEPOINT_SYMBOL(dma_fence_enable_signal); +EXPORT_TRACEPOINT_SYMBOL(dma_fence_signaled); diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c index 9bf06042619a..8196a179fdc2 100644 --- a/drivers/dma-buf/dma-fence.c +++ b/drivers/dma-buf/dma-fence.c @@ -24,13 +24,6 @@ #include #include -#define CREATE_TRACE_POINTS -#include - -EXPORT_TRACEPOINT_SYMBOL(dma_fence_emit); -EXPORT_TRACEPOINT_SYMBOL(dma_fence_enable_signal); -EXPORT_TRACEPOINT_SYMBOL(dma_fence_signaled); - static DEFINE_SPINLOCK(dma_fence_stub_lock); static struct dma_fence dma_fence_stub; @@ -136,7 +129,6 @@ EXPORT_SYMBOL(dma_fence_context_alloc); */ int dma_fence_signal_locked(struct dma_fence *fence) { - struct dma_fence_cb *cur, *tmp; int ret = 0; lockdep_assert_held(fence->lock); @@ -144,7 +136,7 @@ int dma_fence_signal_locked(struct dma_fence *fence) if (WARN_ON(!fence)) return -EINVAL; - if (test_and_set_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) { + if (!__dma_fence_signal(fence)) { ret = -EINVAL; /* @@ -152,15 +144,10 @@ int dma_fence_signal_locked(struct dma_fence *fence) * still run through all callbacks */ } else { - fence->timestamp = ktime_get(); - set_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags); - trace_dma_fence_signaled(fence); + __dma_fence_signal__timestamp(fence, ktime_get()); } - list_for_each_entry_safe(cur, tmp, &fence->cb_list, node) { - list_del_init(&cur->node); - cur->func(fence, cur); - } + __dma_fence_signal__notify(fence); return ret; } EXPORT_SYMBOL(dma_fence_signal_locked); @@ -185,21 +172,14 @@ int dma_fence_signal(struct dma_fence *fence) if (!fence) return -EINVAL; - if (test_and_set_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) + if (!__dma_fence_signal(fence)) return -EINVAL; - fence->timestamp = ktime_get(); - set_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags); - trace_dma_fence_signaled(fence); + __dma_fence_signal__timestamp(fence, ktime_get()); if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &fence->flags)) { - struct dma_fence_cb *cur, *tmp; - spin_lock_irqsave(fence->lock, flags); - list_for_each_entry_safe(cur, tmp, &fence->cb_list, node) { - list_del_init(&cur->node); - cur->func(fence, cur); - } + __dma_fence_signal__notify(fence); spin_unlock_irqrestore(fence->lock, flags); } return 0; diff --git a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c index c092bdf5f0bf..d1f8572100c3 100644 --- a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c +++ b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c @@ -23,7 +23,6 @@ */ #include -#include #include #include "i915_drv.h" @@ -97,35 +96,6 @@ check_signal_order(struct intel_context *ce, struct i915_request *rq) return true; } -static bool -__dma_fence_signal(struct dma_fence *fence) -{ - return !test_and_set_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags); -} - -static void -__dma_fence_signal__timestamp(struct dma_fence *fence, ktime_t timestamp) -{ - fence->timestamp = timestamp; - set_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags); - trace_dma_fence_signaled(fence); -} - -static void -__dma_fence_signal__notify(struct dma_fence *fence) -{ - struct dma_fence_cb *cur, *tmp; - - lockdep_assert_held(fence->lock); - lockdep_assert_irqs_disabled(); - - list_for_each_entry_safe(cur, tmp, &fence->cb_list, node) { - INIT_LIST_HEAD(&cur->node); - cur->func(fence, cur); - } - INIT_LIST_HEAD(&fence->cb_list); -} - void intel_engine_breadcrumbs_irq(struct intel_engine_cs *engine) { struct intel_breadcrumbs *b = &engine->breadcrumbs; diff --git a/include/linux/dma-fence-types.h b/include/linux/dma-fence-types.h new file mode 100644 index 000000000000..18e7511c0eed --- /dev/null +++ b/include/linux/dma-fence-types.h @@ -0,0 +1,248 @@ +/* + * Fence mechanism for dma-buf to allow for asynchronous dma access + * + * Copyright (C) 2012 Canonical Ltd + * Copyright (C) 2012 Texas Instruments + * + * Authors: + * Rob Clark + * Maarten Lankhorst + * + * 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. + */ + +#ifndef __LINUX_DMA_FENCE_TYPES_H +#define __LINUX_DMA_FENCE_TYPES_H + +#include +#include + +struct dma_fence; +struct dma_fence_ops; +struct dma_fence_cb; + +/** + * struct dma_fence - software synchronization primitive + * @refcount: refcount for this fence + * @ops: dma_fence_ops associated with this fence + * @rcu: used for releasing fence with kfree_rcu + * @cb_list: list of all callbacks to call + * @lock: spin_lock_irqsave used for locking + * @context: execution context this fence belongs to, returned by + * dma_fence_context_alloc() + * @seqno: the sequence number of this fence inside the execution context, + * can be compared to decide which fence would be signaled later. + * @flags: A mask of DMA_FENCE_FLAG_* defined below + * @timestamp: Timestamp when the fence was signaled. + * @error: Optional, only valid if < 0, must be set before calling + * dma_fence_signal, indicates that the fence has completed with an error. + * + * the flags member must be manipulated and read using the appropriate + * atomic ops (bit_*), so taking the spinlock will not be needed most + * of the time. + * + * DMA_FENCE_FLAG_SIGNALED_BIT - fence is already signaled + * DMA_FENCE_FLAG_TIMESTAMP_BIT - timestamp recorded for fence signaling + * DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT - enable_signaling might have been called + * DMA_FENCE_FLAG_USER_BITS - start of the unused bits, can be used by the + * implementer of the fence for its own purposes. Can be used in different + * ways by different fence implementers, so do not rely on this. + * + * Since atomic bitops are used, this is not guaranteed to be the case. + * Particularly, if the bit was set, but dma_fence_signal was called right + * before this bit was set, it would have been able to set the + * DMA_FENCE_FLAG_SIGNALED_BIT, before enable_signaling was called. + * Adding a check for DMA_FENCE_FLAG_SIGNALED_BIT after setting + * DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT closes this race, and makes sure that + * after dma_fence_signal was called, any enable_signaling call will have either + * been completed, or never called at all. + */ +struct dma_fence { + struct kref refcount; + const struct dma_fence_ops *ops; + struct rcu_head rcu; + struct list_head cb_list; + spinlock_t *lock; + u64 context; + u64 seqno; + unsigned long flags; + ktime_t timestamp; + int error; +}; + +enum dma_fence_flag_bits { + DMA_FENCE_FLAG_SIGNALED_BIT, + DMA_FENCE_FLAG_TIMESTAMP_BIT, + DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, + DMA_FENCE_FLAG_USER_BITS, /* must always be last member */ +}; + +typedef void (*dma_fence_func_t)(struct dma_fence *fence, + struct dma_fence_cb *cb); + +/** + * struct dma_fence_cb - callback for dma_fence_add_callback() + * @node: used by dma_fence_add_callback() to append this struct to fence::cb_list + * @func: dma_fence_func_t to call + * + * This struct will be initialized by dma_fence_add_callback(), additional + * data can be passed along by embedding dma_fence_cb in another struct. + */ +struct dma_fence_cb { + struct list_head node; + dma_fence_func_t func; +}; + +/** + * struct dma_fence_ops - operations implemented for fence + * + */ +struct dma_fence_ops { + /** + * @use_64bit_seqno: + * + * True if this dma_fence implementation uses 64bit seqno, false + * otherwise. + */ + bool use_64bit_seqno; + + /** + * @get_driver_name: + * + * Returns the driver name. This is a callback to allow drivers to + * compute the name at runtime, without having it to store permanently + * for each fence, or build a cache of some sort. + * + * This callback is mandatory. + */ + const char * (*get_driver_name)(struct dma_fence *fence); + + /** + * @get_timeline_name: + * + * Return the name of the context this fence belongs to. This is a + * callback to allow drivers to compute the name at runtime, without + * having it to store permanently for each fence, or build a cache of + * some sort. + * + * This callback is mandatory. + */ + const char * (*get_timeline_name)(struct dma_fence *fence); + + /** + * @enable_signaling: + * + * Enable software signaling of fence. + * + * For fence implementations that have the capability for hw->hw + * signaling, they can implement this op to enable the necessary + * interrupts, or insert commands into cmdstream, etc, to avoid these + * costly operations for the common case where only hw->hw + * synchronization is required. This is called in the first + * dma_fence_wait() or dma_fence_add_callback() path to let the fence + * implementation know that there is another driver waiting on the + * signal (ie. hw->sw case). + * + * This function can be called from atomic context, but not + * from irq context, so normal spinlocks can be used. + * + * A return value of false indicates the fence already passed, + * or some failure occurred that made it impossible to enable + * signaling. True indicates successful enabling. + * + * &dma_fence.error may be set in enable_signaling, but only when false + * is returned. + * + * Since many implementations can call dma_fence_signal() even when before + * @enable_signaling has been called there's a race window, where the + * dma_fence_signal() might result in the final fence reference being + * released and its memory freed. To avoid this, implementations of this + * callback should grab their own reference using dma_fence_get(), to be + * released when the fence is signalled (through e.g. the interrupt + * handler). + * + * This callback is optional. If this callback is not present, then the + * driver must always have signaling enabled. + */ + bool (*enable_signaling)(struct dma_fence *fence); + + /** + * @signaled: + * + * Peek whether the fence is signaled, as a fastpath optimization for + * e.g. dma_fence_wait() or dma_fence_add_callback(). Note that this + * callback does not need to make any guarantees beyond that a fence + * once indicates as signalled must always return true from this + * callback. This callback may return false even if the fence has + * completed already, in this case information hasn't propogated throug + * the system yet. See also dma_fence_is_signaled(). + * + * May set &dma_fence.error if returning true. + * + * This callback is optional. + */ + bool (*signaled)(struct dma_fence *fence); + + /** + * @wait: + * + * Custom wait implementation, defaults to dma_fence_default_wait() if + * not set. + * + * The dma_fence_default_wait implementation should work for any fence, as long + * as @enable_signaling works correctly. This hook allows drivers to + * have an optimized version for the case where a process context is + * already available, e.g. if @enable_signaling for the general case + * needs to set up a worker thread. + * + * Must return -ERESTARTSYS if the wait is intr = true and the wait was + * interrupted, and remaining jiffies if fence has signaled, or 0 if wait + * timed out. Can also return other error values on custom implementations, + * which should be treated as if the fence is signaled. For example a hardware + * lockup could be reported like that. + * + * This callback is optional. + */ + signed long (*wait)(struct dma_fence *fence, + bool intr, signed long timeout); + + /** + * @release: + * + * Called on destruction of fence to release additional resources. + * Can be called from irq context. This callback is optional. If it is + * NULL, then dma_fence_free() is instead called as the default + * implementation. + */ + void (*release)(struct dma_fence *fence); + + /** + * @fence_value_str: + * + * Callback to fill in free-form debug info specific to this fence, like + * the sequence number. + * + * This callback is optional. + */ + void (*fence_value_str)(struct dma_fence *fence, char *str, int size); + + /** + * @timeline_value_str: + * + * Fills in the current value of the timeline as a string, like the + * sequence number. Note that the specific fence passed to this function + * should not matter, drivers should only use it to look up the + * corresponding timeline structures. + */ + void (*timeline_value_str)(struct dma_fence *fence, + char *str, int size); +}; + +#endif /* __LINUX_DMA_FENCE_TYPES_H */ diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h index 974717d6ac0c..142eb67e695f 100644 --- a/include/linux/dma-fence.h +++ b/include/linux/dma-fence.h @@ -21,6 +21,7 @@ #ifndef __LINUX_DMA_FENCE_H #define __LINUX_DMA_FENCE_H +#include #include #include #include @@ -30,226 +31,7 @@ #include #include -struct dma_fence; -struct dma_fence_ops; -struct dma_fence_cb; - -/** - * struct dma_fence - software synchronization primitive - * @refcount: refcount for this fence - * @ops: dma_fence_ops associated with this fence - * @rcu: used for releasing fence with kfree_rcu - * @cb_list: list of all callbacks to call - * @lock: spin_lock_irqsave used for locking - * @context: execution context this fence belongs to, returned by - * dma_fence_context_alloc() - * @seqno: the sequence number of this fence inside the execution context, - * can be compared to decide which fence would be signaled later. - * @flags: A mask of DMA_FENCE_FLAG_* defined below - * @timestamp: Timestamp when the fence was signaled. - * @error: Optional, only valid if < 0, must be set before calling - * dma_fence_signal, indicates that the fence has completed with an error. - * - * the flags member must be manipulated and read using the appropriate - * atomic ops (bit_*), so taking the spinlock will not be needed most - * of the time. - * - * DMA_FENCE_FLAG_SIGNALED_BIT - fence is already signaled - * DMA_FENCE_FLAG_TIMESTAMP_BIT - timestamp recorded for fence signaling - * DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT - enable_signaling might have been called - * DMA_FENCE_FLAG_USER_BITS - start of the unused bits, can be used by the - * implementer of the fence for its own purposes. Can be used in different - * ways by different fence implementers, so do not rely on this. - * - * Since atomic bitops are used, this is not guaranteed to be the case. - * Particularly, if the bit was set, but dma_fence_signal was called right - * before this bit was set, it would have been able to set the - * DMA_FENCE_FLAG_SIGNALED_BIT, before enable_signaling was called. - * Adding a check for DMA_FENCE_FLAG_SIGNALED_BIT after setting - * DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT closes this race, and makes sure that - * after dma_fence_signal was called, any enable_signaling call will have either - * been completed, or never called at all. - */ -struct dma_fence { - struct kref refcount; - const struct dma_fence_ops *ops; - struct rcu_head rcu; - struct list_head cb_list; - spinlock_t *lock; - u64 context; - u64 seqno; - unsigned long flags; - ktime_t timestamp; - int error; -}; - -enum dma_fence_flag_bits { - DMA_FENCE_FLAG_SIGNALED_BIT, - DMA_FENCE_FLAG_TIMESTAMP_BIT, - DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, - DMA_FENCE_FLAG_USER_BITS, /* must always be last member */ -}; - -typedef void (*dma_fence_func_t)(struct dma_fence *fence, - struct dma_fence_cb *cb); - -/** - * struct dma_fence_cb - callback for dma_fence_add_callback() - * @node: used by dma_fence_add_callback() to append this struct to fence::cb_list - * @func: dma_fence_func_t to call - * - * This struct will be initialized by dma_fence_add_callback(), additional - * data can be passed along by embedding dma_fence_cb in another struct. - */ -struct dma_fence_cb { - struct list_head node; - dma_fence_func_t func; -}; - -/** - * struct dma_fence_ops - operations implemented for fence - * - */ -struct dma_fence_ops { - /** - * @use_64bit_seqno: - * - * True if this dma_fence implementation uses 64bit seqno, false - * otherwise. - */ - bool use_64bit_seqno; - - /** - * @get_driver_name: - * - * Returns the driver name. This is a callback to allow drivers to - * compute the name at runtime, without having it to store permanently - * for each fence, or build a cache of some sort. - * - * This callback is mandatory. - */ - const char * (*get_driver_name)(struct dma_fence *fence); - - /** - * @get_timeline_name: - * - * Return the name of the context this fence belongs to. This is a - * callback to allow drivers to compute the name at runtime, without - * having it to store permanently for each fence, or build a cache of - * some sort. - * - * This callback is mandatory. - */ - const char * (*get_timeline_name)(struct dma_fence *fence); - - /** - * @enable_signaling: - * - * Enable software signaling of fence. - * - * For fence implementations that have the capability for hw->hw - * signaling, they can implement this op to enable the necessary - * interrupts, or insert commands into cmdstream, etc, to avoid these - * costly operations for the common case where only hw->hw - * synchronization is required. This is called in the first - * dma_fence_wait() or dma_fence_add_callback() path to let the fence - * implementation know that there is another driver waiting on the - * signal (ie. hw->sw case). - * - * This function can be called from atomic context, but not - * from irq context, so normal spinlocks can be used. - * - * A return value of false indicates the fence already passed, - * or some failure occurred that made it impossible to enable - * signaling. True indicates successful enabling. - * - * &dma_fence.error may be set in enable_signaling, but only when false - * is returned. - * - * Since many implementations can call dma_fence_signal() even when before - * @enable_signaling has been called there's a race window, where the - * dma_fence_signal() might result in the final fence reference being - * released and its memory freed. To avoid this, implementations of this - * callback should grab their own reference using dma_fence_get(), to be - * released when the fence is signalled (through e.g. the interrupt - * handler). - * - * This callback is optional. If this callback is not present, then the - * driver must always have signaling enabled. - */ - bool (*enable_signaling)(struct dma_fence *fence); - - /** - * @signaled: - * - * Peek whether the fence is signaled, as a fastpath optimization for - * e.g. dma_fence_wait() or dma_fence_add_callback(). Note that this - * callback does not need to make any guarantees beyond that a fence - * once indicates as signalled must always return true from this - * callback. This callback may return false even if the fence has - * completed already, in this case information hasn't propogated throug - * the system yet. See also dma_fence_is_signaled(). - * - * May set &dma_fence.error if returning true. - * - * This callback is optional. - */ - bool (*signaled)(struct dma_fence *fence); - - /** - * @wait: - * - * Custom wait implementation, defaults to dma_fence_default_wait() if - * not set. - * - * The dma_fence_default_wait implementation should work for any fence, as long - * as @enable_signaling works correctly. This hook allows drivers to - * have an optimized version for the case where a process context is - * already available, e.g. if @enable_signaling for the general case - * needs to set up a worker thread. - * - * Must return -ERESTARTSYS if the wait is intr = true and the wait was - * interrupted, and remaining jiffies if fence has signaled, or 0 if wait - * timed out. Can also return other error values on custom implementations, - * which should be treated as if the fence is signaled. For example a hardware - * lockup could be reported like that. - * - * This callback is optional. - */ - signed long (*wait)(struct dma_fence *fence, - bool intr, signed long timeout); - - /** - * @release: - * - * Called on destruction of fence to release additional resources. - * Can be called from irq context. This callback is optional. If it is - * NULL, then dma_fence_free() is instead called as the default - * implementation. - */ - void (*release)(struct dma_fence *fence); - - /** - * @fence_value_str: - * - * Callback to fill in free-form debug info specific to this fence, like - * the sequence number. - * - * This callback is optional. - */ - void (*fence_value_str)(struct dma_fence *fence, char *str, int size); - - /** - * @timeline_value_str: - * - * Fills in the current value of the timeline as a string, like the - * sequence number. Note that the specific fence passed to this function - * should not matter, drivers should only use it to look up the - * corresponding timeline structures. - */ - void (*timeline_value_str)(struct dma_fence *fence, - char *str, int size); -}; +#include void dma_fence_init(struct dma_fence *fence, const struct dma_fence_ops *ops, spinlock_t *lock, u64 context, u64 seqno); @@ -561,6 +343,35 @@ static inline signed long dma_fence_wait(struct dma_fence *fence, bool intr) struct dma_fence *dma_fence_get_stub(void); u64 dma_fence_context_alloc(unsigned num); +static inline bool +__dma_fence_signal(struct dma_fence *fence) +{ + return !test_and_set_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags); +} + +static inline void +__dma_fence_signal__timestamp(struct dma_fence *fence, ktime_t timestamp) +{ + fence->timestamp = timestamp; + set_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags); + trace_dma_fence_signaled(fence); +} + +static inline void +__dma_fence_signal__notify(struct dma_fence *fence) +{ + struct dma_fence_cb *cur, *tmp; + + lockdep_assert_held(fence->lock); + lockdep_assert_irqs_disabled(); + + list_for_each_entry_safe(cur, tmp, &fence->cb_list, node) { + INIT_LIST_HEAD(&cur->node); + cur->func(fence, cur); + } + INIT_LIST_HEAD(&fence->cb_list); +} + #define DMA_FENCE_TRACE(f, fmt, args...) \ do { \ struct dma_fence *__ff = (f); \