diff options
| author | Uladzislau Rezki <uladzislau.rezki@sony.com> | 2022-02-16 14:52:09 +0100 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2022-05-11 11:38:50 -0700 |
| commit | 28b3ae426598e722cf5d5ab9cc7038791b955a56 (patch) | |
| tree | 3fddab261f875fe8e828bbb42d5a190df6ad8144 /kernel/rcu/Kconfig.debug | |
| parent | 3123109284176b1532874591f7c81f3837bbdc17 (diff) | |
rcu: Introduce CONFIG_RCU_EXP_CPU_STALL_TIMEOUT
Currently both expedited and regular grace period stall warnings use
a single timeout value that with units of seconds. However, recent
Android use cases problem require a sub-100-millisecond expedited RCU CPU
stall warning. Given that expedited RCU grace periods normally complete
in far less than a single millisecond, especially for small systems,
this is not unreasonable.
Therefore introduce the CONFIG_RCU_EXP_CPU_STALL_TIMEOUT kernel
configuration that defaults to 20 msec on Android and remains the same
as that of the non-expedited stall warnings otherwise. It also can be
changed in run-time via: /sys/.../parameters/rcu_exp_cpu_stall_timeout.
[ paulmck: Default of zero to use CONFIG_RCU_STALL_TIMEOUT. ]
Signed-off-by: Uladzislau Rezki <uladzislau.rezki@sony.com>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'kernel/rcu/Kconfig.debug')
| -rw-r--r-- | kernel/rcu/Kconfig.debug | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/kernel/rcu/Kconfig.debug b/kernel/rcu/Kconfig.debug index 4fd64999300f..0b397b5bf846 100644 --- a/kernel/rcu/Kconfig.debug +++ b/kernel/rcu/Kconfig.debug @@ -91,6 +91,20 @@ config RCU_CPU_STALL_TIMEOUT RCU grace period persists, additional CPU stall warnings are printed at more widely spaced intervals. +config RCU_EXP_CPU_STALL_TIMEOUT + int "Expedited RCU CPU stall timeout in milliseconds" + depends on RCU_STALL_COMMON + range 0 21000 + default 20 if ANDROID + default 0 if !ANDROID + help + If a given expedited RCU grace period extends more than the + specified number of milliseconds, a CPU stall warning is printed. + If the RCU grace period persists, additional CPU stall warnings + are printed at more widely spaced intervals. A value of zero + says to use the RCU_CPU_STALL_TIMEOUT value converted from + seconds to milliseconds. + config RCU_TRACE bool "Enable tracing for RCU" depends on DEBUG_KERNEL |