]> www.infradead.org Git - users/dwmw2/linux.git/commit
ptp: Add vDSO-style vmclock support vmclock-4
authorDavid Woodhouse <dwmw@amazon.co.uk>
Mon, 10 Jun 2024 14:10:11 +0000 (15:10 +0100)
committerDavid Woodhouse <dwmw@amazon.co.uk>
Wed, 21 Aug 2024 21:46:46 +0000 (22:46 +0100)
commitfa599e8ee31bd8c56b342ed3800a9b2c400a51fb
treeb7a9831a167ddc3752703fa87ee3879a8adc3086
parentb311c1b497e51a628aa89e7cb954481e5f9dced2
ptp: Add vDSO-style vmclock support

The vmclock "device" provides a shared memory region with precision clock
information. By using shared memory, it is safe across Live Migration.

Like the KVM PTP clock, this can convert TSC-based cross timestamps into
KVM clock values. Unlike the KVM PTP clock, it does so only when such is
actually helpful.

The memory region of the device is also exposed to userspace so it can be
read or memory mapped by application which need reliable notification of
clock disruptions.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
drivers/ptp/Kconfig
drivers/ptp/Makefile
drivers/ptp/ptp_vmclock.c [new file with mode: 0644]
include/uapi/linux/vmclock-abi.h [new file with mode: 0644]