Many embedded systems don't need the full POSIX timer support. Configuring them out provides a nice kernel image size reduction.
When POSIX timers are configured out, the PTP clock subsystem should be left out as well. However a bunch of ethernet drivers currently *select* it in their Kconfig entries. Therefore some more tweaks were needed to break that hard dependency for those drivers to still be configured in if desired. It was agreed that the best path upstream for those patches is via John Stultz's timer tree. Previous itterations of those patches and the discussion threads can be found here: https://lkml.org/lkml/2016/9/14/992 https://lkml.org/lkml/2016/9/14/803 https://lkml.org/lkml/2016/9/8/793 Changes from v1: - Add a warning for the case where PTP clock subsystem is modular and a driver providing a clock is built-in rather than silently ignoring it. Suggested by Jiri Benc. - Added Eugenia Emantayev's reviewed-by tag. diffstat: drivers/Makefile | 2 +- drivers/net/ethernet/adi/Kconfig | 8 +- drivers/net/ethernet/amd/Kconfig | 2 +- drivers/net/ethernet/amd/xgbe/xgbe-main.c | 6 +- drivers/net/ethernet/broadcom/Kconfig | 4 +- drivers/net/ethernet/cavium/Kconfig | 2 +- drivers/net/ethernet/freescale/Kconfig | 2 +- drivers/net/ethernet/intel/Kconfig | 10 +- drivers/net/ethernet/intel/e1000e/ptp.c | 2 +- drivers/net/ethernet/intel/i40e/i40e_ptp.c | 2 +- drivers/net/ethernet/intel/igb/igb_ptp.c | 2 +- drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c | 2 +- drivers/net/ethernet/mellanox/mlx4/Kconfig | 2 +- drivers/net/ethernet/mellanox/mlx4/en_clock.c | 2 +- drivers/net/ethernet/mellanox/mlx5/core/Kconfig | 2 +- .../net/ethernet/mellanox/mlx5/core/en_clock.c | 2 +- drivers/net/ethernet/renesas/Kconfig | 2 +- drivers/net/ethernet/samsung/Kconfig | 2 +- drivers/net/ethernet/sfc/Kconfig | 2 +- drivers/net/ethernet/sfc/ptp.c | 14 +-- drivers/net/ethernet/stmicro/stmmac/Kconfig | 2 +- .../net/ethernet/stmicro/stmmac/stmmac_ptp.c | 2 +- drivers/net/ethernet/ti/Kconfig | 2 +- drivers/net/ethernet/tile/Kconfig | 2 +- drivers/ptp/Kconfig | 14 ++- include/linux/posix-timers.h | 28 ++++- include/linux/ptp_clock_kernel.h | 64 +++++++--- include/linux/sched.h | 10 ++ init/Kconfig | 17 +++ kernel/signal.c | 4 + kernel/time/Kconfig | 1 + kernel/time/Makefile | 10 +- kernel/time/posix-stubs.c | 118 ++++++++++++++++++ 33 files changed, 282 insertions(+), 64 deletions(-)
