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	MES allocates process level doorbells, but there is no userspace client to consume it. It was only being used for the MES ring tests (in kernel), and was written by kernel doorbell write. The previous patch of this series has changed the MES ring test code to use kernel level MES doorbells. This patch now cleans up the process level doorbell allocation code which is not required. Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Christian Koenig <christian.koenig@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Shashank Sharma <shashank.sharma@amd.com> Signed-off-by: Arvind Yadav <arvind.yadav@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
		
			
				
	
	
		
			453 lines
		
	
	
	
		
			14 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			453 lines
		
	
	
	
		
			14 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Copyright 2019 Advanced Micro Devices, Inc.
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 *
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 * Permission is hereby granted, free of charge, to any person obtaining a
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 * copy of this software and associated documentation files (the "Software"),
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 * to deal in the Software without restriction, including without limitation
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 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
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 * and/or sell copies of the Software, and to permit persons to whom the
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 * Software is furnished to do so, subject to the following conditions:
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 *
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 * The above copyright notice and this permission notice shall be included in
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 * all copies or substantial portions of the Software.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
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 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
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 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
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 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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 * OTHER DEALINGS IN THE SOFTWARE.
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 *
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 */
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#ifndef __AMDGPU_MES_H__
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#define __AMDGPU_MES_H__
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#include "amdgpu_irq.h"
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#include "kgd_kfd_interface.h"
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#include "amdgpu_gfx.h"
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#include "amdgpu_doorbell.h"
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#include <linux/sched/mm.h>
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#define AMDGPU_MES_MAX_COMPUTE_PIPES        8
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#define AMDGPU_MES_MAX_GFX_PIPES            2
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#define AMDGPU_MES_MAX_SDMA_PIPES           2
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#define AMDGPU_MES_API_VERSION_SHIFT	12
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#define AMDGPU_MES_FEAT_VERSION_SHIFT	24
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#define AMDGPU_MES_VERSION_MASK		0x00000fff
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#define AMDGPU_MES_API_VERSION_MASK	0x00fff000
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#define AMDGPU_MES_FEAT_VERSION_MASK	0xff000000
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enum amdgpu_mes_priority_level {
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	AMDGPU_MES_PRIORITY_LEVEL_LOW       = 0,
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	AMDGPU_MES_PRIORITY_LEVEL_NORMAL    = 1,
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	AMDGPU_MES_PRIORITY_LEVEL_MEDIUM    = 2,
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	AMDGPU_MES_PRIORITY_LEVEL_HIGH      = 3,
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	AMDGPU_MES_PRIORITY_LEVEL_REALTIME  = 4,
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	AMDGPU_MES_PRIORITY_NUM_LEVELS
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};
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#define AMDGPU_MES_PROC_CTX_SIZE 0x1000 /* one page area */
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#define AMDGPU_MES_GANG_CTX_SIZE 0x1000 /* one page area */
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struct amdgpu_mes_funcs;
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enum admgpu_mes_pipe {
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	AMDGPU_MES_SCHED_PIPE = 0,
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	AMDGPU_MES_KIQ_PIPE,
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	AMDGPU_MAX_MES_PIPES = 2,
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};
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struct amdgpu_mes {
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	struct amdgpu_device            *adev;
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	struct mutex                    mutex_hidden;
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	struct idr                      pasid_idr;
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	struct idr                      gang_id_idr;
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	struct idr                      queue_id_idr;
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	struct ida                      doorbell_ida;
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	spinlock_t                      queue_id_lock;
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	uint32_t			sched_version;
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	uint32_t			kiq_version;
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	uint32_t                        total_max_queue;
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	uint32_t                        max_doorbell_slices;
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	uint64_t                        default_process_quantum;
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	uint64_t                        default_gang_quantum;
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	struct amdgpu_ring              ring;
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	spinlock_t                      ring_lock;
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	const struct firmware           *fw[AMDGPU_MAX_MES_PIPES];
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	/* mes ucode */
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	struct amdgpu_bo		*ucode_fw_obj[AMDGPU_MAX_MES_PIPES];
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	uint64_t			ucode_fw_gpu_addr[AMDGPU_MAX_MES_PIPES];
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	uint32_t			*ucode_fw_ptr[AMDGPU_MAX_MES_PIPES];
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	uint64_t                        uc_start_addr[AMDGPU_MAX_MES_PIPES];
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	/* mes ucode data */
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	struct amdgpu_bo		*data_fw_obj[AMDGPU_MAX_MES_PIPES];
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	uint64_t			data_fw_gpu_addr[AMDGPU_MAX_MES_PIPES];
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	uint32_t			*data_fw_ptr[AMDGPU_MAX_MES_PIPES];
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	uint64_t                        data_start_addr[AMDGPU_MAX_MES_PIPES];
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	/* eop gpu obj */
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	struct amdgpu_bo		*eop_gpu_obj[AMDGPU_MAX_MES_PIPES];
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	uint64_t                        eop_gpu_addr[AMDGPU_MAX_MES_PIPES];
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	void                            *mqd_backup[AMDGPU_MAX_MES_PIPES];
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	struct amdgpu_irq_src	        irq[AMDGPU_MAX_MES_PIPES];
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	uint32_t                        vmid_mask_gfxhub;
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	uint32_t                        vmid_mask_mmhub;
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	uint32_t                        compute_hqd_mask[AMDGPU_MES_MAX_COMPUTE_PIPES];
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	uint32_t                        gfx_hqd_mask[AMDGPU_MES_MAX_GFX_PIPES];
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	uint32_t                        sdma_hqd_mask[AMDGPU_MES_MAX_SDMA_PIPES];
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	uint32_t                        aggregated_doorbells[AMDGPU_MES_PRIORITY_NUM_LEVELS];
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	uint32_t                        sch_ctx_offs;
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	uint64_t			sch_ctx_gpu_addr;
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	uint64_t			*sch_ctx_ptr;
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	uint32_t			query_status_fence_offs;
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	uint64_t			query_status_fence_gpu_addr;
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	uint64_t			*query_status_fence_ptr;
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	uint32_t                        read_val_offs;
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	uint64_t			read_val_gpu_addr;
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	uint32_t			*read_val_ptr;
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	uint32_t			saved_flags;
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	/* initialize kiq pipe */
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	int                             (*kiq_hw_init)(struct amdgpu_device *adev);
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	int                             (*kiq_hw_fini)(struct amdgpu_device *adev);
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	/* MES doorbells */
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	uint32_t			db_start_dw_offset;
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	uint32_t			num_mes_dbs;
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	unsigned long			*doorbell_bitmap;
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	/* ip specific functions */
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	const struct amdgpu_mes_funcs   *funcs;
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};
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struct amdgpu_mes_process {
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	int			pasid;
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	struct			amdgpu_vm *vm;
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	uint64_t		pd_gpu_addr;
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	struct amdgpu_bo 	*proc_ctx_bo;
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	uint64_t 		proc_ctx_gpu_addr;
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	void 			*proc_ctx_cpu_ptr;
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	uint64_t 		process_quantum;
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	struct 			list_head gang_list;
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	uint32_t 		doorbell_index;
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	struct mutex		doorbell_lock;
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};
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struct amdgpu_mes_gang {
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	int 				gang_id;
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	int 				priority;
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	int 				inprocess_gang_priority;
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	int 				global_priority_level;
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	struct list_head 		list;
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	struct amdgpu_mes_process 	*process;
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	struct amdgpu_bo 		*gang_ctx_bo;
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	uint64_t 			gang_ctx_gpu_addr;
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	void 				*gang_ctx_cpu_ptr;
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	uint64_t 			gang_quantum;
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	struct list_head 		queue_list;
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};
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struct amdgpu_mes_queue {
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	struct list_head 		list;
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	struct amdgpu_mes_gang 		*gang;
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	int 				queue_id;
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	uint64_t 			doorbell_off;
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	struct amdgpu_bo		*mqd_obj;
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	void				*mqd_cpu_ptr;
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	uint64_t 			mqd_gpu_addr;
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	uint64_t 			wptr_gpu_addr;
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	int 				queue_type;
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	int 				paging;
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	struct amdgpu_ring 		*ring;
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};
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struct amdgpu_mes_queue_properties {
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	int 			queue_type;
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	uint64_t                hqd_base_gpu_addr;
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	uint64_t                rptr_gpu_addr;
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	uint64_t                wptr_gpu_addr;
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	uint64_t                wptr_mc_addr;
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	uint32_t                queue_size;
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	uint64_t                eop_gpu_addr;
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	uint32_t                hqd_pipe_priority;
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	uint32_t                hqd_queue_priority;
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	bool 			paging;
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	struct amdgpu_ring 	*ring;
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	/* out */
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	uint64_t       		doorbell_off;
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};
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struct amdgpu_mes_gang_properties {
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	uint32_t 	priority;
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	uint32_t 	gang_quantum;
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	uint32_t 	inprocess_gang_priority;
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	uint32_t 	priority_level;
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	int 		global_priority_level;
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};
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struct mes_add_queue_input {
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	uint32_t	process_id;
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	uint64_t	page_table_base_addr;
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	uint64_t	process_va_start;
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	uint64_t	process_va_end;
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	uint64_t	process_quantum;
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	uint64_t	process_context_addr;
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	uint64_t	gang_quantum;
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	uint64_t	gang_context_addr;
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	uint32_t	inprocess_gang_priority;
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	uint32_t	gang_global_priority_level;
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	uint32_t	doorbell_offset;
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	uint64_t	mqd_addr;
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	uint64_t	wptr_addr;
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	uint64_t	wptr_mc_addr;
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	uint32_t	queue_type;
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	uint32_t	paging;
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	uint32_t        gws_base;
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	uint32_t        gws_size;
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	uint64_t	tba_addr;
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	uint64_t	tma_addr;
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	uint32_t	trap_en;
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	uint32_t	skip_process_ctx_clear;
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	uint32_t	is_kfd_process;
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	uint32_t	is_aql_queue;
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	uint32_t	queue_size;
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	uint32_t	exclusively_scheduled;
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};
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struct mes_remove_queue_input {
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	uint32_t	doorbell_offset;
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	uint64_t	gang_context_addr;
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};
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struct mes_unmap_legacy_queue_input {
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	enum amdgpu_unmap_queues_action    action;
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	uint32_t                           queue_type;
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	uint32_t                           doorbell_offset;
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	uint32_t                           pipe_id;
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	uint32_t                           queue_id;
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	uint64_t                           trail_fence_addr;
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	uint64_t                           trail_fence_data;
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};
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struct mes_suspend_gang_input {
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	bool		suspend_all_gangs;
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	uint64_t	gang_context_addr;
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	uint64_t	suspend_fence_addr;
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	uint32_t	suspend_fence_value;
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};
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struct mes_resume_gang_input {
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	bool		resume_all_gangs;
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	uint64_t	gang_context_addr;
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};
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enum mes_misc_opcode {
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	MES_MISC_OP_WRITE_REG,
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	MES_MISC_OP_READ_REG,
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	MES_MISC_OP_WRM_REG_WAIT,
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	MES_MISC_OP_WRM_REG_WR_WAIT,
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	MES_MISC_OP_SET_SHADER_DEBUGGER,
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};
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struct mes_misc_op_input {
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	enum mes_misc_opcode op;
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	union {
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		struct {
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			uint32_t                  reg_offset;
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			uint64_t                  buffer_addr;
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		} read_reg;
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		struct {
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			uint32_t                  reg_offset;
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			uint32_t                  reg_value;
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		} write_reg;
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		struct {
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			uint32_t                   ref;
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			uint32_t                   mask;
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			uint32_t                   reg0;
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			uint32_t                   reg1;
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		} wrm_reg;
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		struct {
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			uint64_t process_context_addr;
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			union {
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				struct {
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					uint64_t single_memop : 1;
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					uint64_t single_alu_op : 1;
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					uint64_t reserved: 30;
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				};
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				uint32_t u32all;
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			} flags;
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			uint32_t spi_gdbg_per_vmid_cntl;
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			uint32_t tcp_watch_cntl[4];
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			uint32_t trap_en;
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		} set_shader_debugger;
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	};
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};
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struct amdgpu_mes_funcs {
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	int (*add_hw_queue)(struct amdgpu_mes *mes,
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			    struct mes_add_queue_input *input);
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	int (*remove_hw_queue)(struct amdgpu_mes *mes,
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			       struct mes_remove_queue_input *input);
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	int (*unmap_legacy_queue)(struct amdgpu_mes *mes,
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				  struct mes_unmap_legacy_queue_input *input);
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	int (*suspend_gang)(struct amdgpu_mes *mes,
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			    struct mes_suspend_gang_input *input);
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	int (*resume_gang)(struct amdgpu_mes *mes,
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			   struct mes_resume_gang_input *input);
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	int (*misc_op)(struct amdgpu_mes *mes,
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		       struct mes_misc_op_input *input);
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};
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#define amdgpu_mes_kiq_hw_init(adev) (adev)->mes.kiq_hw_init((adev))
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#define amdgpu_mes_kiq_hw_fini(adev) (adev)->mes.kiq_hw_fini((adev))
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int amdgpu_mes_ctx_get_offs(struct amdgpu_ring *ring, unsigned int id_offs);
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int amdgpu_mes_init_microcode(struct amdgpu_device *adev, int pipe);
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int amdgpu_mes_init(struct amdgpu_device *adev);
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void amdgpu_mes_fini(struct amdgpu_device *adev);
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int amdgpu_mes_create_process(struct amdgpu_device *adev, int pasid,
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			      struct amdgpu_vm *vm);
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void amdgpu_mes_destroy_process(struct amdgpu_device *adev, int pasid);
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int amdgpu_mes_add_gang(struct amdgpu_device *adev, int pasid,
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			struct amdgpu_mes_gang_properties *gprops,
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			int *gang_id);
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int amdgpu_mes_remove_gang(struct amdgpu_device *adev, int gang_id);
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int amdgpu_mes_suspend(struct amdgpu_device *adev);
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int amdgpu_mes_resume(struct amdgpu_device *adev);
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int amdgpu_mes_add_hw_queue(struct amdgpu_device *adev, int gang_id,
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			    struct amdgpu_mes_queue_properties *qprops,
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			    int *queue_id);
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int amdgpu_mes_remove_hw_queue(struct amdgpu_device *adev, int queue_id);
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int amdgpu_mes_unmap_legacy_queue(struct amdgpu_device *adev,
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				  struct amdgpu_ring *ring,
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				  enum amdgpu_unmap_queues_action action,
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				  u64 gpu_addr, u64 seq);
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uint32_t amdgpu_mes_rreg(struct amdgpu_device *adev, uint32_t reg);
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int amdgpu_mes_wreg(struct amdgpu_device *adev,
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		    uint32_t reg, uint32_t val);
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int amdgpu_mes_reg_wait(struct amdgpu_device *adev, uint32_t reg,
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			uint32_t val, uint32_t mask);
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int amdgpu_mes_reg_write_reg_wait(struct amdgpu_device *adev,
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				  uint32_t reg0, uint32_t reg1,
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				  uint32_t ref, uint32_t mask);
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int amdgpu_mes_set_shader_debugger(struct amdgpu_device *adev,
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				uint64_t process_context_addr,
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				uint32_t spi_gdbg_per_vmid_cntl,
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				const uint32_t *tcp_watch_cntl,
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				uint32_t flags,
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				bool trap_en);
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int amdgpu_mes_add_ring(struct amdgpu_device *adev, int gang_id,
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			int queue_type, int idx,
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			struct amdgpu_mes_ctx_data *ctx_data,
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			struct amdgpu_ring **out);
 | 
						|
void amdgpu_mes_remove_ring(struct amdgpu_device *adev,
 | 
						|
			    struct amdgpu_ring *ring);
 | 
						|
 | 
						|
uint32_t amdgpu_mes_get_aggregated_doorbell_index(struct amdgpu_device *adev,
 | 
						|
						   enum amdgpu_mes_priority_level prio);
 | 
						|
 | 
						|
int amdgpu_mes_ctx_alloc_meta_data(struct amdgpu_device *adev,
 | 
						|
				   struct amdgpu_mes_ctx_data *ctx_data);
 | 
						|
void amdgpu_mes_ctx_free_meta_data(struct amdgpu_mes_ctx_data *ctx_data);
 | 
						|
int amdgpu_mes_ctx_map_meta_data(struct amdgpu_device *adev,
 | 
						|
				 struct amdgpu_vm *vm,
 | 
						|
				 struct amdgpu_mes_ctx_data *ctx_data);
 | 
						|
int amdgpu_mes_ctx_unmap_meta_data(struct amdgpu_device *adev,
 | 
						|
				   struct amdgpu_mes_ctx_data *ctx_data);
 | 
						|
 | 
						|
int amdgpu_mes_self_test(struct amdgpu_device *adev);
 | 
						|
 | 
						|
int amdgpu_mes_doorbell_process_slice(struct amdgpu_device *adev);
 | 
						|
 | 
						|
/*
 | 
						|
 * MES lock can be taken in MMU notifiers.
 | 
						|
 *
 | 
						|
 * A bit more detail about why to set no-FS reclaim with MES lock:
 | 
						|
 *
 | 
						|
 * The purpose of the MMU notifier is to stop GPU access to memory so
 | 
						|
 * that the Linux VM subsystem can move pages around safely. This is
 | 
						|
 * done by preempting user mode queues for the affected process. When
 | 
						|
 * MES is used, MES lock needs to be taken to preempt the queues.
 | 
						|
 *
 | 
						|
 * The MMU notifier callback entry point in the driver is
 | 
						|
 * amdgpu_mn_invalidate_range_start_hsa. The relevant call chain from
 | 
						|
 * there is:
 | 
						|
 * amdgpu_amdkfd_evict_userptr -> kgd2kfd_quiesce_mm ->
 | 
						|
 * kfd_process_evict_queues -> pdd->dev->dqm->ops.evict_process_queues
 | 
						|
 *
 | 
						|
 * The last part of the chain is a function pointer where we take the
 | 
						|
 * MES lock.
 | 
						|
 *
 | 
						|
 * The problem with taking locks in the MMU notifier is, that MMU
 | 
						|
 * notifiers can be called in reclaim-FS context. That's where the
 | 
						|
 * kernel frees up pages to make room for new page allocations under
 | 
						|
 * memory pressure. While we are running in reclaim-FS context, we must
 | 
						|
 * not trigger another memory reclaim operation because that would
 | 
						|
 * recursively reenter the reclaim code and cause a deadlock. The
 | 
						|
 * memalloc_nofs_save/restore calls guarantee that.
 | 
						|
 *
 | 
						|
 * In addition we also need to avoid lock dependencies on other locks taken
 | 
						|
 * under the MES lock, for example reservation locks. Here is a possible
 | 
						|
 * scenario of a deadlock:
 | 
						|
 * Thread A: takes and holds reservation lock | triggers reclaim-FS |
 | 
						|
 * MMU notifier | blocks trying to take MES lock
 | 
						|
 * Thread B: takes and holds MES lock | blocks trying to take reservation lock
 | 
						|
 *
 | 
						|
 * In this scenario Thread B gets involved in a deadlock even without
 | 
						|
 * triggering a reclaim-FS operation itself.
 | 
						|
 * To fix this and break the lock dependency chain you'd need to either:
 | 
						|
 * 1. protect reservation locks with memalloc_nofs_save/restore, or
 | 
						|
 * 2. avoid taking reservation locks under the MES lock.
 | 
						|
 *
 | 
						|
 * Reservation locks are taken all over the kernel in different subsystems, we
 | 
						|
 * have no control over them and their lock dependencies.So the only workable
 | 
						|
 * solution is to avoid taking other locks under the MES lock.
 | 
						|
 * As a result, make sure no reclaim-FS happens while holding this lock anywhere
 | 
						|
 * to prevent deadlocks when an MMU notifier runs in reclaim-FS context.
 | 
						|
 */
 | 
						|
static inline void amdgpu_mes_lock(struct amdgpu_mes *mes)
 | 
						|
{
 | 
						|
	mutex_lock(&mes->mutex_hidden);
 | 
						|
	mes->saved_flags = memalloc_noreclaim_save();
 | 
						|
}
 | 
						|
 | 
						|
static inline void amdgpu_mes_unlock(struct amdgpu_mes *mes)
 | 
						|
{
 | 
						|
	memalloc_noreclaim_restore(mes->saved_flags);
 | 
						|
	mutex_unlock(&mes->mutex_hidden);
 | 
						|
}
 | 
						|
#endif /* __AMDGPU_MES_H__ */
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