From: Stephen Hemminger <stephen@networkplumber.org>
To: Antoine Tenart <atenart@kernel.org>
Cc: davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com,
edumazet@google.com, netdev@vger.kernel.org,
gregkh@linuxfoundation.org, mhocko@suse.com
Subject: Re: [RFC PATCH net-next 0/4] net-sysfs: remove rtnl_trylock/restart_syscall use
Date: Wed, 18 Oct 2023 11:15:47 -0700 [thread overview]
Message-ID: <20231018111547.0be5532d@hermes.local> (raw)
In-Reply-To: <20231018154804.420823-1-atenart@kernel.org>
On Wed, 18 Oct 2023 17:47:42 +0200
Antoine Tenart <atenart@kernel.org> wrote:
> Some time ago we tried to improve the rtnl_trylock/restart_syscall
> situation[1]. What happens is when there is rtnl contention, userspace
> accessing net sysfs attributes will spin and experience delays. This can
> happen in different situations, when sysfs attributes are accessed
> (networking daemon, configuration, monitoring) while operations under
> rtnl are performed (veth creation, driver configuration, etc). A few
> improvements can be done in userspace to ease things, like using the
> netlink interface instead, or polling less (or more selectively) the
> attributes; but in the end the root cause is always there and this keeps
> happening from time to time.
What attribute is not exposed by netlink, and only by sysfs?
There will always be more overhead using sysfs.
That doesn't mean the locking should not be fixed, just that better
to avoid the situation if possible.
next prev parent reply other threads:[~2023-10-18 18:15 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-10-18 15:47 [RFC PATCH net-next 0/4] net-sysfs: remove rtnl_trylock/restart_syscall use Antoine Tenart
2023-10-18 15:47 ` [RFC PATCH net-next 1/4] net-sysfs: remove rtnl_trylock from device attributes Antoine Tenart
2023-10-18 16:49 ` Greg KH
2023-10-19 8:13 ` Antoine Tenart
2023-10-19 15:37 ` Greg KH
2023-10-18 18:13 ` Stephen Hemminger
2023-10-19 7:48 ` Antoine Tenart
2025-01-02 22:36 ` Jakub Kicinski
2025-01-03 8:41 ` Eric Dumazet
2025-01-07 16:30 ` Antoine Tenart
2025-01-07 17:06 ` Jakub Kicinski
2025-01-16 13:36 ` Antoine Tenart
2025-01-16 23:42 ` Jakub Kicinski
2025-01-16 23:43 ` Jakub Kicinski
2025-01-17 8:26 ` Antoine Tenart
2023-10-18 15:47 ` [RFC PATCH net-next 2/4] net-sysfs: move queue attribute groups outside the default groups Antoine Tenart
2023-10-18 15:47 ` [RFC PATCH net-next 3/4] net-sysfs: prevent uncleared queues from being re-added Antoine Tenart
2023-10-18 15:47 ` [RFC PATCH net-next 4/4] net-sysfs: remove rtnl_trylock from queue attributes Antoine Tenart
2023-10-18 15:57 ` [RFC PATCH net-next 0/4] net-sysfs: remove rtnl_trylock/restart_syscall use Stephen Hemminger
2023-10-18 16:34 ` Antoine Tenart
2023-10-18 18:15 ` Stephen Hemminger [this message]
2023-10-19 7:47 ` Antoine Tenart
2023-10-19 14:54 ` Stephen Hemminger
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