From 5c8806a037ad4f53259146060b32600566475e29 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 6 Jan 2012 15:10:44 -0800 Subject: rcu: Move RCU_TRACE to lib/Kconfig.debug The RCU_TRACE kernel parameter has always been intended for debugging, not for production use. Formalize this by moving RCU_TRACE from init/Kconfig to lib/Kconfig.debug. Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney --- lib/Kconfig.debug | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 8745ac7d1f7..3cc419d05f2 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -927,6 +927,16 @@ config RCU_CPU_STALL_VERBOSE Say Y if you want to enable such checks. +config RCU_TRACE + bool "Enable tracing for RCU" + depends on DEBUG_KERNEL + help + This option provides tracing in RCU which presents stats + in debugfs for debugging RCU implementation. + + Say Y here if you want to enable RCU tracing + Say N if you are unsure. + config KPROBES_SANITY_TEST bool "Kprobes sanity tests" depends on DEBUG_KERNEL -- cgit v1.2.3-18-g5258 From a858af2875fb291d0f4b0a4419fefbf03c2379c0 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 16 Jan 2012 13:29:10 -0800 Subject: rcu: Print scheduling-clock information on RCU CPU stall-warning messages There have been situations where RCU CPU stall warnings were caused by issues in scheduling-clock timer initialization. To make it easier to track these down, this commit causes the RCU CPU stall-warning messages to print out the number of scheduling-clock interrupts taken in the current grace period for each stalled CPU. Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney --- lib/Kconfig.debug | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 3cc419d05f2..d27a2aa3e81 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -927,6 +927,20 @@ config RCU_CPU_STALL_VERBOSE Say Y if you want to enable such checks. +config RCU_CPU_STALL_INFO + bool "Print additional diagnostics on RCU CPU stall" + depends on (TREE_RCU || TREE_PREEMPT_RCU) && DEBUG_KERNEL + default n + help + For each stalled CPU that is aware of the current RCU grace + period, print out additional per-CPU diagnostic information + regarding scheduling-clock ticks, idle state, and, + for RCU_FAST_NO_HZ kernels, idle-entry state. + + Say N if you are unsure. + + Say Y if you want to enable such diagnostics. + config RCU_TRACE bool "Enable tracing for RCU" depends on DEBUG_KERNEL -- cgit v1.2.3-18-g5258