b22f21f7a5
When we are trying to timestamp a TX packet, there may be occasions when the TX timestamp register is still not updated with the latest timestamp even if the timestamp packet descriptor is marked as complete. This usually happens in cases where the system is under stress or flow control is affecting the transmit side. We will solve this problem by saving the snapshot of the timestamp register when we are posting the TX descriptor. At this time, the register contains previously timestamped packet's value and valid timestamp of the current packet must be different than this. Upon completion of the current descriptor, we will check if the timestamp register is updated or not before timestamping the skb. If not updated, we will schedule the ptp worker to fetch the updated time later and timestamp the skb. Also now we restrict number of outstanding PTP TX packet requests to 1. Reported-by: Simon White <Simon.White@viavisolutions.com> Link: https://lore.kernel.org/netdev/CACKFLikGdN9XPtWk-fdrzxdcD=+bv-GHBvfVfSpJzHY7hrW39g@mail.gmail.com/ Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> Reviewed-by: Andy Gospodarek <gospo@broadcom.com> Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.