[PATCH 0/5] context_tracking: Flatter archs not using exception_enter/exit()

From: Frederic Weisbecker
Date: Mon Oct 05 2020 - 06:49:33 EST


In order to be able to turn on/off nohz_full at runtime, we'll need
the archs to give up saving the context tracking state on the task stack
because this forces context tracking to run system wide, even on CPUs
that don't have nohz_full enabled.

Now being able to do so require sane entry code meeting some
requirements that at least x86 just achieved recently (I haven't checked
other archs yet).

git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
core/isolation

HEAD: d52271b6d5d02ead1916d65b013d11a7d90501b9

Thanks,
Frederic
---

Frederic Weisbecker (5):
context_tracking: Introduce HAVE_CONTEXT_TRACKING_OFFSTACK
context_tracking: Don't implement exception_enter/exit() on CONFIG_HAVE_CONTEXT_TRACKING_OFFSTACK
sched: Detect call to schedule from critical entry code
context_tracking: Only define schedule_user() on !HAVE_CONTEXT_TRACKING_OFFSTACK archs
x86: Support HAVE_CONTEXT_TRACKING_OFFSTACK


arch/Kconfig | 17 +++++++++++++++++
arch/x86/Kconfig | 1 +
include/linux/context_tracking.h | 6 ++++--
kernel/sched/core.c | 3 ++-
4 files changed, 24 insertions(+), 3 deletions(-)