f-stack/dpdk/drivers/raw/ioat/dpdk_idxd_cfg.py

91 lines
3.1 KiB
Python
Executable File

#!/usr/bin/env python3
# SPDX-License-Identifier: BSD-3-Clause
# Copyright(c) 2020 Intel Corporation
"""
Configure an entire Intel DSA instance, using idxd kernel driver, for DPDK use
"""
import sys
import argparse
import os
import os.path
class SysfsDir:
"Used to read/write paths in a sysfs directory"
def __init__(self, path):
self.path = path
def read_int(self, filename):
"Return a value from sysfs file"
with open(os.path.join(self.path, filename)) as f:
return int(f.readline())
def write_values(self, values):
"write dictionary, where key is filename and value is value to write"
for filename, contents in values.items():
with open(os.path.join(self.path, filename), "w") as f:
f.write(str(contents))
def get_drv_dir(dtype):
"Get the sysfs path for the driver, either 'idxd' or 'user'"
drv_dir = "/sys/bus/dsa/drivers/" + dtype
if not os.path.exists(drv_dir):
return "/sys/bus/dsa/drivers/dsa"
return drv_dir
def configure_dsa(dsa_id, queues):
"Configure the DSA instance with appropriate number of queues"
dsa_dir = SysfsDir(f"/sys/bus/dsa/devices/dsa{dsa_id}")
max_groups = dsa_dir.read_int("max_groups")
max_engines = dsa_dir.read_int("max_engines")
max_queues = dsa_dir.read_int("max_work_queues")
max_work_queues_size = dsa_dir.read_int("max_work_queues_size")
nb_queues = min(queues, max_queues)
if queues > nb_queues:
print(f"Setting number of queues to max supported value: {max_queues}")
# we want one engine per group, and no more engines than queues
nb_groups = min(max_engines, max_groups, nb_queues)
for grp in range(nb_groups):
dsa_dir.write_values({f"engine{dsa_id}.{grp}/group_id": grp})
# configure each queue
for q in range(nb_queues):
wq_dir = SysfsDir(os.path.join(dsa_dir.path, f"wq{dsa_id}.{q}"))
wq_dir.write_values({"group_id": q % nb_groups,
"type": "user",
"mode": "dedicated",
"name": f"dpdk_wq{dsa_id}.{q}",
"priority": 1,
"max_batch_size": 1024,
"size": int(max_work_queues_size / nb_queues)})
# enable device and then queues
idxd_dir = SysfsDir(get_drv_dir("idxd"))
idxd_dir.write_values({"bind": f"dsa{dsa_id}"})
user_dir = SysfsDir(get_drv_dir("user"))
for q in range(nb_queues):
user_dir.write_values({"bind": f"wq{dsa_id}.{q}"})
def main(args):
"Main function, does arg parsing and calls config function"
arg_p = argparse.ArgumentParser(
description="Configure whole DSA device instance for DPDK use")
arg_p.add_argument('dsa_id', type=int, help="DSA instance number")
arg_p.add_argument('-q', metavar='queues', type=int, default=255,
help="Number of queues to set up")
parsed_args = arg_p.parse_args(args[1:])
configure_dsa(parsed_args.dsa_id, parsed_args.q)
if __name__ == "__main__":
main(sys.argv)