path: root/lib
diff options
authorPaul E. McKenney <>2008-10-02 16:06:39 -0700
committerIngo Molnar <>2008-10-03 10:36:08 +0200
commit2133b5d7ff531bc15a923db4a6a50bf96c561be9 (patch)
tree5917515eaec573fbc3d4a734769d6184beb83dbb /lib
parentb5259d944279d0b7e78a83849a352d8ba0447c4c (diff)
rcu: RCU-based detection of stalled CPUs for Classic RCU
This patch adds stalled-CPU detection to Classic RCU. This capability is enabled by a new config variable CONFIG_RCU_CPU_STALL_DETECTOR, which defaults disabled. This is a debugging feature to detect infinite loops in kernel code, not something that non-kernel-hackers would be expected to care about. This feature can detect looping CPUs in !PREEMPT builds and looping CPUs with preemption disabled in PREEMPT builds. This is essentially a port of this functionality from the treercu patch, replacing the stall debug patch that is already in tip/core/rcu (commit 67182ae1c4). The changes from the patch in tip/core/rcu include making the config variable name match that in treercu, changing from seconds to jiffies to avoid spurious warnings, and printing a boot message when this feature is enabled. Signed-off-by: Paul E. McKenney <> Signed-off-by: Ingo Molnar <>
Diffstat (limited to 'lib')
1 files changed, 1 insertions, 1 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index ccede1aeab38..9fee969dd60e 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -597,7 +597,7 @@ config RCU_TORTURE_TEST_RUNNABLE
Say N here if you want the RCU torture tests to start only
after being manually enabled via /proc.
bool "Check for stalled CPUs delaying RCU grace periods"
depends on CLASSIC_RCU
default n