From: Paul E. McKenney Date: Thu, 2 Oct 2008 23:06:39 +0000 (-0700) Subject: rcu: RCU-based detection of stalled CPUs for Classic RCU X-Git-Tag: v2.6.28-rc1~723^2~2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2133b5d7ff531bc15a923db4a6a50bf96c561be9;p=pandora-kernel.git 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 --- Reading git-diff-tree failed