drm/amdkfd: map multiple processes to HW scheduler

Allow HWS to to execute multiple processes on the hardware
concurrently. The number of concurrent processes is limited by
the number of VMIDs allocated to the HWS.

A module parameter can be used for limiting this further or turn
it off altogether (mainly for debugging purposes).

Signed-off-by: Yong Zhao <yong.zhao@amd.com>
Signed-off-by: Jay Cornwall <Jay.Cornwall@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device.c b/drivers/gpu/drm/amd/amdkfd/kfd_device.c
index 4f05eacca786a0f10d29cf697a3ee53e873513c4..a8fa33a08de301fde244f1584e8a9edeeea40775 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/kfd_device.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_device.c
@@ -238,6 +238,17 @@ bool kgd2kfd_device_init(struct kfd_dev *kfd,
        kfd->vm_info.vmid_num_kfd = kfd->vm_info.last_vmid_kfd
                        - kfd->vm_info.first_vmid_kfd + 1;
 
+       /* Verify module parameters regarding mapped process number*/
+       if ((hws_max_conc_proc < 0)
+                       || (hws_max_conc_proc > kfd->vm_info.vmid_num_kfd)) {
+               dev_err(kfd_device,
+                       "hws_max_conc_proc %d must be between 0 and %d, use %d instead\n",
+                       hws_max_conc_proc, kfd->vm_info.vmid_num_kfd,
+                       kfd->vm_info.vmid_num_kfd);
+               kfd->max_proc_per_quantum = kfd->vm_info.vmid_num_kfd;
+       } else
+               kfd->max_proc_per_quantum = hws_max_conc_proc;
+
        /* calculate max size of mqds needed for queues */
        size = max_num_of_queues_per_device *
                        kfd->device_info->mqd_size_aligned;

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_module.c b/drivers/gpu/drm/amd/amdkfd/kfd_module.c
index ee8adf654cd007320b7610a3b69a5feb5551d808..4e060c864c214a15e7a9028e9ed9c9646dc3cdbd 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/kfd_module.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_module.c
@@ -50,6 +50,11 @@ module_param(sched_policy, int, 0444);
 MODULE_PARM_DESC(sched_policy,
        "Scheduling policy (0 = HWS (Default), 1 = HWS without over-subscription, 2 = Non-HWS (Used for debugging only)");
 
+int hws_max_conc_proc = 8;
+module_param(hws_max_conc_proc, int, 0444);
+MODULE_PARM_DESC(hws_max_conc_proc,
+       "Max # processes HWS can execute concurrently when sched_policy=0 (0 = no concurrency, #VMIDs for KFD = Maximum(default))");
+
 int cwsr_enable = 1;
 module_param(cwsr_enable, int, 0444);
 MODULE_PARM_DESC(cwsr_enable, "CWSR enable (0 = Off, 1 = On (Default))");

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_packet_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_packet_manager.c
index 69c147a83591801a4cac386b33adee40eb3c062c..0b7092e59bf948145356efa15f94804b2de8ef02 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/kfd_packet_manager.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_packet_manager.c
@@ -57,13 +57,24 @@ static void pm_calc_rlib_size(struct packet_manager *pm,
 {
        unsigned int process_count, queue_count;
        unsigned int map_queue_size;
+       unsigned int max_proc_per_quantum = 1;
+       struct kfd_dev *dev = pm->dqm->dev;
 
        process_count = pm->dqm->processes_count;
        queue_count = pm->dqm->queue_count;
 
-       /* check if there is over subscription*/
+       /* check if there is over subscription
+        * Note: the arbitration between the number of VMIDs and
+        * hws_max_conc_proc has been done in
+        * kgd2kfd_device_init().
+        */
        *over_subscription = false;
-       if ((process_count > 1) || queue_count > get_queues_num(pm->dqm)) {
+
+       if (dev->max_proc_per_quantum > 1)
+               max_proc_per_quantum = dev->max_proc_per_quantum;
+
+       if ((process_count > max_proc_per_quantum) ||
+           queue_count > get_queues_num(pm->dqm)) {
                *over_subscription = true;
                pr_debug("Over subscribed runlist\n");
        }
@@ -116,10 +127,24 @@ static int pm_create_runlist(struct packet_manager *pm, uint32_t *buffer,
                        uint64_t ib, size_t ib_size_in_dwords, bool chain)
 {
        struct pm4_mes_runlist *packet;
+       int concurrent_proc_cnt = 0;
+       struct kfd_dev *kfd = pm->dqm->dev;
 
        if (WARN_ON(!ib))
                return -EFAULT;
 
+       /* Determine the number of processes to map together to HW:
+        * it can not exceed the number of VMIDs available to the
+        * scheduler, and it is determined by the smaller of the number
+        * of processes in the runlist and kfd module parameter
+        * hws_max_conc_proc.
+        * Note: the arbitration between the number of VMIDs and
+        * hws_max_conc_proc has been done in
+        * kgd2kfd_device_init().
+        */
+       concurrent_proc_cnt = min(pm->dqm->processes_count,
+                       kfd->max_proc_per_quantum);
+
        packet = (struct pm4_mes_runlist *)buffer;
 
        memset(buffer, 0, sizeof(struct pm4_mes_runlist));
@@ -130,6 +155,7 @@ static int pm_create_runlist(struct packet_manager *pm, uint32_t *buffer,
        packet->bitfields4.chain = chain ? 1 : 0;
        packet->bitfields4.offload_polling = 0;
        packet->bitfields4.valid = 1;
+       packet->bitfields4.process_cnt = concurrent_proc_cnt;
        packet->ordinal2 = lower_32_bits(ib);
        packet->bitfields3.ib_base_hi = upper_32_bits(ib);
 

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
index a668764679958bf66e0a50283dc884c7e352ffe4..1edab2199f0b8ef66dbc12b7b83e3f2f58b866e0 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
@@ -88,6 +88,12 @@ extern int max_num_of_queues_per_device;
 /* Kernel module parameter to specify the scheduling policy */
 extern int sched_policy;
 
+/*
+ * Kernel module parameter to specify the maximum process
+ * number per HW scheduler
+ */
+extern int hws_max_conc_proc;
+
 extern int cwsr_enable;
 
 /*
@@ -214,6 +220,9 @@ struct kfd_dev {
        /* Debug manager */
        struct kfd_dbgmgr           *dbgmgr;
 
+       /* Maximum process number mapped to HW scheduler */
+       unsigned int max_proc_per_quantum;
+
        /* CWSR */
        bool cwsr_enabled;
        const void *cwsr_isa;