From 75c27f119b6475d95374bdad872c6938b5c26196 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 11 Jun 2015 15:22:43 -0700 Subject: rcu: Remove CONFIG_RCU_CPU_STALL_INFO The CONFIG_RCU_CPU_STALL_INFO has been default-y for a couple of releases with no complaints, so it is time to eliminate this Kconfig option entirely, so that the long-form RCU CPU stall warnings cannot be disabled. This commit does just that. Signed-off-by: Paul E. McKenney --- Documentation/RCU/stallwarn.txt | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-) (limited to 'Documentation/RCU/stallwarn.txt') diff --git a/Documentation/RCU/stallwarn.txt b/Documentation/RCU/stallwarn.txt index b57c0c1cdac6..046f32637b95 100644 --- a/Documentation/RCU/stallwarn.txt +++ b/Documentation/RCU/stallwarn.txt @@ -26,12 +26,6 @@ CONFIG_RCU_CPU_STALL_TIMEOUT Stall-warning messages may be enabled and disabled completely via /sys/module/rcupdate/parameters/rcu_cpu_stall_suppress. -CONFIG_RCU_CPU_STALL_INFO - - This kernel configuration parameter causes the stall warning to - print out additional per-CPU diagnostic information, including - information on scheduling-clock ticks and RCU's idle-CPU tracking. - RCU_STALL_DELAY_DELTA Although the lockdep facility is extremely useful, it does add @@ -101,15 +95,13 @@ interact. Please note that it is not possible to entirely eliminate this sort of false positive without resorting to things like stop_machine(), which is overkill for this sort of problem. -If the CONFIG_RCU_CPU_STALL_INFO kernel configuration parameter is set, -more information is printed with the stall-warning message, for example: +Recent kernels will print a long form of the stall-warning message: INFO: rcu_preempt detected stall on CPU 0: (63959 ticks this GP) idle=241/3fffffffffffffff/0 softirq=82/543 (t=65000 jiffies) -In kernels with CONFIG_RCU_FAST_NO_HZ, even more information is -printed: +In kernels with CONFIG_RCU_FAST_NO_HZ, more information is printed: INFO: rcu_preempt detected stall on CPU 0: (64628 ticks this GP) idle=dd5/3fffffffffffffff/0 softirq=82/543 last_accelerate: a345/d342 nonlazy_posted: 25 .D -- cgit v1.2.3