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

From: Jeff Kirsher
Date: Tue Aug 22 2017 - 20:30:22 EST


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 preemtable. This is due to udelay using busy-wait
> loops
> while usleep_rang uses hrtimers instead. It is recommended to use
> udelay when the delay is <10us since at that precision overhead
> of
> usleep_range hrtimer setup causes issues. However, the replaced
> calls
> are for 50us and 100us so this should not be not an issue.
>
> Signed-off-by: nxf23276 <matthew.tan_1@xxxxxxx>
> ---
> drivers/net/ethernet/intel/e1000e/phy.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)

First of all, your name is nxf23276? Really??

Second, you titled your patch that you were makeding changes to e1000
driver, yet you are asking to modify e1000e. Just based on these 2
needed changes, I am dropping your patch.

Attachment: signature.asc
Description: This is a digitally signed message part