lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Mon, 14 Sep 2020 16:58:35 -0700 (PDT)
From:   David Miller <>
Subject: Re: [PATCH net-next 1/2] tcp: return EPOLLOUT from tcp_poll only
 when notsent_bytes is half the limit

From: Soheil Hassas Yeganeh <>
Date: Mon, 14 Sep 2020 17:52:09 -0400

> From: Soheil Hassas Yeganeh <>
> If there was any event available on the TCP socket, tcp_poll()
> will be called to retrieve all the events.  In tcp_poll(), we call
> sk_stream_is_writeable() which returns true as long as we are at least
> one byte below notsent_lowat.  This will result in quite a few
> spurious EPLLOUT and frequent tiny sendmsg() calls as a result.
> Similar to sk_stream_write_space(), use __sk_stream_is_writeable
> with a wake value of 1, so that we set EPOLLOUT only if half the
> space is available for write.
> Signed-off-by: Soheil Hassas Yeganeh <>
> Signed-off-by: Eric Dumazet <>


Powered by blists - more mailing lists