Vitaly Kuznetsov 4f9bac039a hv_utils: drop .getcrosststamp() support from PTP driver ... Turns out that our implementation of .getcrosststamp() never actually worked. Hyper-V is sending time samples every 5 seconds and this is too much for get_device_system_crosststamp() as it's interpolation algorithm (which nobody is currently using in kernel, btw) accounts for a 'slow' device but we're not slow in Hyper-V, our time reference is too far away. .getcrosststamp() is not currently used, get_device_system_crosststamp() almost always returns -EINVAL and client falls back to using PTP_SYS_OFFSET so this patch doesn't change much. I also tried doing interpolation manually (e.g. the same way hv_ptp_gettime() works and it turns out that we're getting even lower quality: PTP_SYS_OFFSET_PRECISE with manual interpolation: * PHC0 0 3 37 4 -3974ns[-5338ns] +/- 977ns * PHC0 0 3 77 7 +2227ns[+3184ns] +/- 576ns * PHC0 0 3 177 10 +3060ns[+5220ns] +/- 548ns * PHC0 0 3 377 12 +3937ns[+4371ns] +/- 1414ns * PHC0 0 3 377 6 +764ns[+1240ns] +/- 1047ns * PHC0 0 3 377 7 -1210ns[-3731ns] +/- 479ns * PHC0 0 3 377 9 +153ns[-1019ns] +/- 406ns * PHC0 0 3 377 12 -872ns[-1793ns] +/- 443ns * PHC0 0 3 377 5 +701ns[+3599ns] +/- 426ns * PHC0 0 3 377 5 -923ns[ -375ns] +/- 1062ns PTP_SYS_OFFSET: * PHC0 0 3 7 5 +72ns[+8020ns] +/- 251ns * PHC0 0 3 17 5 -885ns[-3661ns] +/- 254ns * PHC0 0 3 37 6 -454ns[-5732ns] +/- 258ns * PHC0 0 3 77 10 +1183ns[+3754ns] +/- 164ns * PHC0 0 3 377 5 +579ns[+1137ns] +/- 110ns * PHC0 0 3 377 7 +501ns[+1064ns] +/- 96ns * PHC0 0 3 377 9 +1641ns[+3342ns] +/- 106ns * PHC0 0 3 377 8 -47ns[ +77ns] +/- 160ns * PHC0 0 3 377 5 +54ns[ +107ns] +/- 102ns * PHC0 0 3 377 8 -354ns[ -617ns] +/- 89ns This fact wasn't noticed during the initial testing of the PTP device somehow but got revealed now. Let's just drop .getcrosststamp() implementation for now as it doesn't seem to be suitable for us. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2017-05-25 15:42:42 +02:00
..
channel_mgmt.c	Drivers: hv: vmbus: Fix rescind handling	2017-05-18 16:55:28 +02:00
channel.c	Drivers: hv: vmbus: Fix rescind handling	2017-05-18 16:55:28 +02:00
connection.c	Drivers: hv: vmbus: Fix rescind handling	2017-05-18 16:55:28 +02:00
hv_balloon.c	vmbus: remove useless return's	2017-03-17 15:10:48 +09:00
hv_fcopy.c	Merge 4.11-rc4 into char-misc-next	2017-03-27 09:13:04 +02:00
hv_kvp.c	HV: properly delay KVP packets when negotiation is in progress	2017-05-18 16:55:28 +02:00
hv_snapshot.c	Merge 4.11-rc4 into char-misc-next	2017-03-27 09:13:04 +02:00
hv_util.c	hv_utils: drop .getcrosststamp() support from PTP driver	2017-05-25 15:42:42 +02:00
hv_utils_transport.c	Drivers: hv: util: move waiting for release to hv_utils_transport itself	2017-03-16 16:42:00 +09:00
hv_utils_transport.h	Drivers: hv: util: move waiting for release to hv_utils_transport itself	2017-03-16 16:42:00 +09:00
hv.c	Drivers: hv: vmbus: Get the current time from the current clocksource	2017-05-25 15:42:42 +02:00
hyperv_vmbus.h	Drivers: hv: vmbus: Fix rescind handling	2017-05-18 16:55:28 +02:00
Kconfig	x86/hyperv: Implement hv_get_tsc_page()	2017-03-11 14:47:28 +01:00
Makefile	Drivers: hv: util: introduce hv_utils_transport abstraction	2015-05-24 12:17:41 -07:00
ring_buffer.c	char/misc patches for 4.12-rc1	2017-05-04 19:15:35 -07:00
vmbus_drv.c	Drivers: hv: vmbus: Fix rescind handling	2017-05-18 16:55:28 +02:00