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Subject: RE: [PATCH 0/2] introduce PM QoS interface  
Date: Wed, 20 Mar 2024 15:05:12 +0100
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Thread-Topic: [PATCH 0/2] introduce PM QoS interface  
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From: =?iso-8859-1?Q?Morten_Br=F8rup?= <mb@smartsharesystems.com>
To: "Huisong Li" <lihuisong@huawei.com>,
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> From: Huisong Li [mailto:lihuisong@huawei.com]
> Sent: Wednesday, 20 March 2024 11.55
>=20
> The system-wide CPU latency QoS limit has a positive impact on the =
idle
> state selection in cpuidle governor.
>=20
> Linux creates a cpu_dma_latency device under '/dev' directory to =
obtain the
> CPU latency QoS limit on system and send the QoS request for =
userspace.
> Please see the PM QoS framework in the following link:
> https://docs.kernel.org/power/pm_qos_interface.html?highlight=3Dqos
> This feature is supported by kernel-v2.6.25.
>=20
> The deeper the idle state, the lower the power consumption, but the =
longer
> the resume time. Some service are delay sensitive and very except the =
low
> resume time, like interrupt packet receiving mode.
>=20
> So this series introduce PM QoS interface.

This looks like a 1:1 wrapper for a Linux kernel feature.
Does Windows or BSD offer something similar?

Furthermore, any high-res timing should use nanoseconds, not =
microseconds or milliseconds.
I realize that the Linux kernel only uses microseconds for these APIs, =
but the DPDK API should use nanoseconds.