diff options
Diffstat (limited to 'meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.14.71/2059-drm-amdgpu-Add-SPSC-queue-to-scheduler.patch')
| -rw-r--r-- | meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.14.71/2059-drm-amdgpu-Add-SPSC-queue-to-scheduler.patch | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.14.71/2059-drm-amdgpu-Add-SPSC-queue-to-scheduler.patch b/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.14.71/2059-drm-amdgpu-Add-SPSC-queue-to-scheduler.patch new file mode 100644 index 00000000..6f39befe --- /dev/null +++ b/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.14.71/2059-drm-amdgpu-Add-SPSC-queue-to-scheduler.patch @@ -0,0 +1,148 @@ +From 7e4d35a371d7d7716c18e702f1bf5fb7229f7fb9 Mon Sep 17 00:00:00 2001 +From: Andrey Grodzovsky <Andrey.Grodzovsky@amd.com> +Date: Thu, 12 Oct 2017 16:41:39 -0400 +Subject: [PATCH 2059/4131] drm/amdgpu: Add SPSC queue to scheduler. +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +It is intended to sabstitute the bounded fifo we are currently +using. + +Signed-off-by: Andrey Grodzovsky <Andrey.Grodzovsky@amd.com> +Reviewed-by: Christian König <christian.koenig@amd.com> +--- + drivers/gpu/drm/amd/scheduler/spsc_queue.h | 121 +++++++++++++++++++++++++++++ + 1 file changed, 121 insertions(+) + create mode 100644 drivers/gpu/drm/amd/scheduler/spsc_queue.h + +diff --git a/drivers/gpu/drm/amd/scheduler/spsc_queue.h b/drivers/gpu/drm/amd/scheduler/spsc_queue.h +new file mode 100644 +index 0000000..5902f35 +--- /dev/null ++++ b/drivers/gpu/drm/amd/scheduler/spsc_queue.h +@@ -0,0 +1,121 @@ ++/* ++ * Copyright 2017 Advanced Micro Devices, Inc. ++ * ++ * 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. ++ * ++ */ ++ ++#ifndef AMD_SCHEDULER_SPSC_QUEUE_H_ ++#define AMD_SCHEDULER_SPSC_QUEUE_H_ ++ ++#include <linux/atomic.h> ++ ++/** SPSC lockless queue */ ++ ++struct spsc_node { ++ ++ /* Stores spsc_node* */ ++ struct spsc_node *next; ++}; ++ ++struct spsc_queue { ++ ++ struct spsc_node *head; ++ ++ /* atomic pointer to struct spsc_node* */ ++ atomic_long_t tail; ++ ++ atomic_t job_count; ++}; ++ ++static inline void spsc_queue_init(struct spsc_queue *queue) ++{ ++ queue->head = NULL; ++ atomic_long_set(&queue->tail, (long)&queue->head); ++ atomic_set(&queue->job_count, 0); ++} ++ ++static inline struct spsc_node *spsc_queue_peek(struct spsc_queue *queue) ++{ ++ return queue->head; ++} ++ ++static inline int spsc_queue_count(struct spsc_queue *queue) ++{ ++ return atomic_read(&queue->job_count); ++} ++ ++static inline bool spsc_queue_push(struct spsc_queue *queue, struct spsc_node *node) ++{ ++ struct spsc_node **tail; ++ ++ node->next = NULL; ++ ++ preempt_disable(); ++ ++ tail = (struct spsc_node **)atomic_long_xchg(&queue->tail, (long)&node->next); ++ WRITE_ONCE(*tail, node); ++ atomic_inc(&queue->job_count); ++ ++ /* ++ * In case of first element verify new node will be visible to the consumer ++ * thread when we ping the kernel thread that there is new work to do. ++ */ ++ smp_wmb(); ++ ++ preempt_enable(); ++ ++ return tail == &queue->head; ++} ++ ++ ++static inline struct spsc_node *spsc_queue_pop(struct spsc_queue *queue) ++{ ++ struct spsc_node *next, *node; ++ ++ /* Verify reading from memory and not the cache */ ++ smp_rmb(); ++ ++ node = READ_ONCE(queue->head); ++ ++ if (!node) ++ return NULL; ++ ++ next = READ_ONCE(node->next); ++ WRITE_ONCE(queue->head, next); ++ ++ if (unlikely(!next)) { ++ /* slowpath for the last element in the queue */ ++ ++ if (atomic_long_cmpxchg(&queue->tail, ++ (long)&node->next, (long) &queue->head) != (long)&node->next) { ++ /* Updating tail failed wait for new next to appear */ ++ do { ++ smp_rmb(); ++ } while (unlikely(!(queue->head = READ_ONCE(node->next)))); ++ } ++ } ++ ++ atomic_dec(&queue->job_count); ++ return node; ++} ++ ++ ++ ++#endif /* AMD_SCHEDULER_SPSC_QUEUE_H_ */ +-- +2.7.4 + |