linux/include
Thomas Gleixner 8ae0ae6737 rcu: Provide rcu_irq_exit_preempt()
Interrupts and exceptions invoke rcu_irq_enter() on entry and need to
invoke rcu_irq_exit() before they either return to the interrupted code or
invoke the scheduler due to preemption.

The general assumption is that RCU idle code has to have preemption
disabled so that a return from interrupt cannot schedule. So the return
from interrupt code invokes rcu_irq_exit() and preempt_schedule_irq().

If there is any imbalance in the rcu_irq/nmi* invocations or RCU idle code
had preemption enabled then this goes unnoticed until the CPU goes idle or
some other RCU check is executed.

Provide rcu_irq_exit_preempt() which can be invoked from the
interrupt/exception return code in case that preemption is enabled. It
invokes rcu_irq_exit() and contains a few sanity checks in case that
CONFIG_PROVE_RCU is enabled to catch such issues directly.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134904.364456424@linutronix.de
History 2020-05-19 15:51:21 +02:00
..
acpi Additional ACPI updates for 5.7-rc1 2020-04-06 10:35:06 -07:00
asm-generic vmlinux.lds.h: Create section for protection against instrumentation 2020-05-19 15:47:20 +02:00
clocksource pwm: omap-dmtimer: Drop unused header file 2020-03-30 18:03:06 +02:00
crypto crypto: curve25519 - do not pollute dispatcher based on assembler 2020-04-09 00:01:59 +09:00
drm drm/bridge: analogix_dp: Split bind() into probe() and real bind() 2020-04-09 10:29:35 +02:00
dt-bindings RISC-V Patches for the 5.7 Merge Window, Part 1 2020-04-09 10:51:30 -07:00
keys KEYS: Don't write out to userspace while holding key semaphore 2020-03-29 12:40:41 +01:00
kunit kunit: subtests should be indented 4 spaces according to TAP 2020-03-26 14:08:41 -06:00
kvm KVM: arm64: GICv4.1: Allow SGIs to switch between HW and SW interrupts 2020-03-24 12:15:51 +00:00
linux rcu: Provide rcu_irq_exit_preempt() 2020-05-19 15:51:21 +02:00
math-emu nds32: Mark expected switch fall-throughs 2019-08-29 11:06:56 -05:00
media media: cec-notifier: make cec_notifier_get_conn() static 2020-03-20 09:02:45 +01:00
misc auxdisplay: charlcd: move charlcd.h to drivers/auxdisplay 2019-08-08 19:59:17 +02:00
net net: flow_offload: skip hw stats check for FLOW_ACTION_HW_STATS_DONT_CARE 2020-05-06 20:13:10 -07:00
pcmcia It's been a relatively busy cycle for docs: 2019-07-09 12:34:26 -07:00
ras RAS: Use consistent types for UUIDs 2019-01-25 16:40:40 +01:00
rdma IB/mlx5: Expose UAR object and its alloc/destroy commands 2020-03-27 12:59:04 -03:00
scsi SCSI misc on 20200402 2020-04-02 17:03:53 -07:00
soc net: dsa: ocelot: the MAC table on Felix is twice as large 2020-05-06 17:15:24 -07:00
sound ASoC: Fixes for v5.7 2020-04-21 21:41:36 +02:00
target scsi: target: fix hang when multiple threads try to destroy the same iscsi session 2020-03-26 21:47:47 -04:00
trace block-5.7-2020-05-09 2020-05-10 11:16:07 -07:00
uapi uapi: revert flexible-array conversions 2020-05-04 11:30:15 -05:00
vdso vdso/datapage: Use correct clock mode name in comment 2020-04-20 19:19:52 +02:00
video video: Replace zero-length array with flexible-array member 2020-03-02 16:32:17 +01:00
xen xen: Use evtchn_type_t as a type for event channels 2020-04-07 12:12:54 +02:00