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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-24 08:46:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-24 08:46:03 -0700 |
| commit | cf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch) | |
| tree | 757a3d280760c654767631cab5ad8af2d86d1848 /include/drm/spsc_queue.h | |
| download | linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip | |
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij:
"Core changes:
- Use the non-blocking mux_state_try_select() in the generic MUX pin
control back-end
- Free pin maps on pinctrl_generic_to_map() failure in the core
helpers
New hardware pin control:
- Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC
(this is for the low power audio, LPASS = Low Power Audio SubSystem
portions)
- Upboard support on top of the Intel pin controller
- Apple T6030 and T6031 support (just compatible strings)
- Samsung Exynos 8855 SoC
- Mediatek MT6858 SoC
- Rockchip RK3308B and RV1106 SoCs
- Airoha EN7523 and AN7563 SoCs
Improvements:
- Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable
- Qualcomm improvements on top of the Qualcomm PDC (power domain
controller) irqchip improvements from tglx:s tree
- Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups
- The NPCM8xx driver has been put into shape fixing many pin and
group definitions
- Some non-urgent Tegra 264 pin assignments are fixed up
- Some non-urgent fixups to Airoha AN7581 and AN7583 registers and
pin assignments, missing features etc"
* tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits)
dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema
pinctrl: meson: sync some modify from A4
pinctrl: meson: a4: Add input enable pin configuration
pinctrl: realtek: rtd1625: remove unused group name spdif_sel
pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13
dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema
Revert "Merge branch 'ib-rsk7204' into devel"
pinctrl: rockchip: Add RV1106 pinctrl support
dt-bindings: pinctrl: rockchip: Add RV1106 compatible
pinctrl: rockchip: Decode drive strength in the get function
pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable
pinctrl: airoha: add support of an7563 SoC
dt-bindings: pinctrl: airoha: add support of an7563 pin controller
pinctrl: airoha: try to find chip scu node by phandle first
pinctrl: airoha: add support of en7523 SoC
dt-bindings: pinctrl: airoha: add support of en7523 pin controller
pinctrl: airoha: an7583: add support for olt pinmux
pinctrl: airoha: an7583: add support for pon_alt pinmux
pinctrl: airoha: an7583: add support for npu_uart pinmux
dt-bindings: pinctrl: airoha: an7583: add missed features
...
Diffstat (limited to 'include/drm/spsc_queue.h')
| -rw-r--r-- | include/drm/spsc_queue.h | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/include/drm/spsc_queue.h b/include/drm/spsc_queue.h new file mode 100644 index 000000000..ee9df8cc6 --- /dev/null +++ b/include/drm/spsc_queue.h @@ -0,0 +1,124 @@ +/* + * 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 DRM_SCHEDULER_SPSC_QUEUE_H_ +#define DRM_SCHEDULER_SPSC_QUEUE_H_ + +#include <linux/atomic.h> +#include <linux/preempt.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(); + + atomic_inc(&queue->job_count); + smp_mb__after_atomic(); + + tail = (struct spsc_node **)atomic_long_xchg(&queue->tail, (long)&node->next); + WRITE_ONCE(*tail, node); + + /* + * 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 /* DRM_SCHEDULER_SPSC_QUEUE_H_ */ |
