Re: [PATCH] e1000: changed some expensive calls of udelay to usleep_range

2017-08-22 Thread Jeff Kirsher
On Tue, 2017-08-22 at 16:02 -0500, nxf23276 wrote: > Calls to udelay are not preemtable by userspace so userspace > applications experience a large (~200us) latency when running on > core > 0. Instead usleep_range can be used to be more friendly to > userspace > since it is preemtab

[PATCH] e1000: changed some expensive calls of udelay to usleep_range

2017-08-22 Thread nxf23276
Calls to udelay are not preemtable by userspace so userspace applications experience a large (~200us) latency when running on core 0. Instead usleep_range can be used to be more friendly to userspace since it is preemtable. This is due to udelay using busy-wait loops while uslee