OpenCloudOS-Kernel/include
Grygorii Strashko d9535cb7b7 ptp: introduce ptp auxiliary worker
Many PTP drivers required to perform some asynchronous or periodic work,
like periodically handling PHC counter overflow or handle delayed timestamp
for RX/TX network packets. In most of the cases, such work is implemented
using workqueues. Unfortunately, Kernel workqueues might introduce
significant delay in work scheduling under high system load and on -RT,
which could cause misbehavior of PTP drivers due to internal counter
overflow, for example, and there is no way to tune its execution policy and
priority manuallly.

Hence, The kthread_worker can be used insted of workqueues, as it create
separte named kthread for each worker and its its execution policy and
priority can be configured using chrt tool.

This prblem was reported for two drivers TI CPSW CPTS and dp83640, so
instead of modifying each of these driver it was proposed to add PTP
auxiliary worker to the PHC subsystem.

The patch adds PTP auxiliary worker in PHC subsystem using kthread_worker
and kthread_delayed_work and introduces two new PHC subsystem APIs:

- long (*do_aux_work)(struct ptp_clock_info *ptp) callback in
ptp_clock_info structure, which driver should assign if it require to
perform asynchronous or periodic work. Driver should return the delay of
the PTP next auxiliary work scheduling time (>=0) or negative value in case
further scheduling is not required.

- int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay) which
allows schedule PTP auxiliary work.

The name of kthread_worker thread corresponds PTP PHC device name "ptp%d".

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-01 15:22:55 -07:00
..
acpi ACPI: NUMA: add missing include in acpi_numa.h 2017-07-24 22:27:43 +02:00
asm-generic Merge branch 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-15 11:17:52 -07:00
clocksource
crypto crypto: engine - replace pr_xxx by dev_xxx 2017-06-19 14:19:54 +08:00
drm i915, amd and some core fixes + mediatek color support 2017-07-13 11:26:18 -07:00
dt-bindings Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2017-07-15 10:59:54 -07:00
keys
kvm KVM: arm64: vgic-v3: Add hook to handle guest GICv3 sysreg accesses at EL2 2017-06-15 09:44:59 +01:00
linux ptp: introduce ptp auxiliary worker 2017-08-01 15:22:55 -07:00
math-emu
media main drm pull for v4.13 2017-07-09 18:48:37 -07:00
memory
misc cxl: Export library to support IBM XSL 2017-07-03 23:07:03 +10:00
net udp6: fix socket leak on early demux 2017-07-29 14:19:03 -07:00
pcmcia
ras trace, ras: add ARM processor error trace event 2017-06-22 18:22:05 +01:00
rdma IB/cma: Fix reference count leak when no ipv4 addresses are set 2017-07-20 11:24:13 -04:00
rxrpc
scsi Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2017-07-13 14:27:32 -07:00
soc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-07-05 12:31:59 -07:00
sound ASoC: Updates for v4.13 2017-07-03 19:51:42 +02:00
target iscsi-target: Add login_keys_workaround attribute for non RFC initiators 2017-07-11 10:56:39 -07:00
trace mm, tree wide: replace __GFP_REPEAT by __GFP_RETRY_MAYFAIL with more useful semantic 2017-07-12 16:26:03 -07:00
uapi TTY/Serial fixes for 4.13-rc2 2017-07-22 09:00:24 -07:00
video imx-drm: cleanups and YUV 4:2:0 memory read/write reduction support 2017-06-16 10:05:38 +10:00
xen xen/balloon: don't online new memory initially 2017-07-23 08:13:18 +02:00