Hi, I am experiencing an interesting issue on some devices. I know the following scenario is not really a real world setup but it will help outline the issue and whether we ought to make a change to LinuxPTP.
Say you have 3 netdevices capable of performing hardware timestamping connected to a switch. You run ptp4l on the first two devices and begin syncing. Then you start ptp4l on the 3rd device, and begin syncing. After a while you kill ptp4l on the 3rd device, but leave the first two syncing. The result in my case is that the 3rd device's driver complains about latched Rx timestamp registers and times out. This occurs, I believe, because the hardware performs the Rx timestamp and puts it into RX timestamp registers before deciding if it should drop the multicast frame (as the multicast subscription should be cleared when the socket goes away, if I understand correctly). Thus, since the launch of ptp4l enabled Rx timestamp settings, the hardware will now continuously trigger rx timestamp hang logic in the driver until the PTP traffic on the other two ports is stopped. My question for this list: Should ptp4l be updated to include a signal handler to trap the exit signal(s) and reset the timestamp logic upon exit? Or is there a better way this could be updated/handled in the kernel? or is this not really an issue, and my driver should be fixed? I don't know if it is really possible to fix my driver, since currently it doesn't know when Rx timestamps have been disabled. Regards, Jake ------------------------------------------------------------------------------ Find and fix application performance issues faster with Applications Manager Applications Manager provides deep performance insights into multiple tiers of your business applications. It resolves application problems quickly and reduces your MTTR. Get your free trial! https://ad.doubleclick.net/ddm/clk/302982198;130105516;z _______________________________________________ Linuxptp-devel mailing list Linuxptp-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-devel
