]> www.infradead.org Git - users/dwmw2/linux.git/commit
ptp: Add vDSO-style vmclock support vmclock-3
authorDavid Woodhouse <dwmw@amazon.co.uk>
Mon, 10 Jun 2024 14:10:11 +0000 (15:10 +0100)
committerDavid Woodhouse <dwmw@amazon.co.uk>
Mon, 29 Jul 2024 10:35:57 +0000 (11:35 +0100)
commite576b2a29f88228f686242ebec0c15bd547e94bf
tree3f116ccb9e5c678220bab8c0389009b88d91d7f4
parent13788269e81b7b0fd5f4c72994da888e673560a7
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]