From: Eric Dumazet <eric.dumazet@gmail.com>
To: Alexander Duyck <alexander.duyck@gmail.com>
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
sridhar.samudrala@intel.com, edumazet@google.com,
davem@davemloft.net, linux-api@vger.kernel.org
Subject: Re: [net-next PATCH v2 5/8] net: Track start of busy loop instead of when it should end
Date: Thu, 23 Mar 2017 18:24:42 -0700 [thread overview]
Message-ID: <1490318682.9687.22.camel@edumazet-glaptop3.roam.corp.google.com> (raw)
In-Reply-To: <20170323213742.12615.85793.stgit@localhost.localdomain>
On Thu, 2017-03-23 at 14:37 -0700, Alexander Duyck wrote:
> From: Alexander Duyck <alexander.h.duyck@intel.com>
>
> The last bit I changed is to move from using a shift by 10 to just using
> NSEC_PER_USEC and using multiplication for any run time calculations and
> division for a few compile time ones. This should be more accurate and
> perform about the same on most architectures since modern CPUs typically
> handle multiplication without too much overhead.
busy polling thread can be preempted for more than 2 seconds.
Using usec instead of nanoseconds gave us 3 orders of magnitude cushion.
We do not need nsec accuracy for busy polling users, if this restricts
range and usability under stress.
next prev parent reply other threads:[~2017-03-24 1:24 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-23 21:36 [net-next PATCH v2 0/8] Add busy poll support for epoll Alexander Duyck
2017-03-23 21:36 ` [net-next PATCH v2 1/8] net: Busy polling should ignore sender CPUs Alexander Duyck
2017-03-23 22:05 ` Eric Dumazet
2017-03-23 21:36 ` [net-next PATCH v2 2/8] tcp: Record Rx hash and NAPI ID in tcp_child_process Alexander Duyck
2017-03-24 1:00 ` Eric Dumazet
2017-03-23 21:36 ` [net-next PATCH v2 3/8] net: Only define skb_mark_napi_id in one spot instead of two Alexander Duyck
2017-03-24 1:02 ` Eric Dumazet
2017-03-23 21:37 ` [net-next PATCH v2 4/8] net: Change return type of sk_busy_loop from bool to void Alexander Duyck
2017-03-24 1:02 ` Eric Dumazet
2017-03-23 21:37 ` [net-next PATCH v2 5/8] net: Track start of busy loop instead of when it should end Alexander Duyck
2017-03-24 1:24 ` Eric Dumazet [this message]
2017-03-24 3:42 ` Alexander Duyck
2017-03-24 4:27 ` Eric Dumazet
2017-03-24 4:38 ` Eric Dumazet
2017-03-24 5:55 ` Alexander Duyck
2017-03-24 11:16 ` Eric Dumazet
2017-03-24 15:48 ` Alexander Duyck
2017-03-23 21:37 ` [net-next PATCH v2 6/8] net: Commonize busy polling code to focus on napi_id instead of socket Alexander Duyck
2017-03-23 22:25 ` Eric Dumazet
2017-03-23 21:37 ` [net-next PATCH v2 7/8] epoll: Add busy poll support to epoll with socket fds Alexander Duyck
2017-03-23 21:38 ` [net-next PATCH v2 8/8] net: Introduce SO_INCOMING_NAPI_ID Alexander Duyck
2017-03-23 22:22 ` Eric Dumazet
2017-03-23 22:43 ` Andy Lutomirski
2017-03-24 0:58 ` Alexander Duyck
2017-03-24 4:47 ` Andy Lutomirski
2017-03-24 5:07 ` Eric Dumazet
2017-03-23 22:07 ` [net-next PATCH v2 0/8] Add busy poll support for epoll Alexei Starovoitov
2017-03-23 22:38 ` Alexander Duyck
2017-03-23 22:49 ` Eric Dumazet
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