From 026ad2835ce6202069e7aa0b11f5f1be4de34550 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Wed, 3 Apr 2013 22:14:11 -0700 Subject: [PATCH] rcu: Drive quiescent-state-forcing delay from HZ Systems with HZ=100 can have slow bootup times due to the default three-jiffy delays between quiescent-state forcing attempts. This commit therefore auto-tunes the RCU_JIFFIES_TILL_FORCE_QS value based on the value of HZ. However, this would break very large systems that require more time between quiescent-state forcing attempts. This commit therefore also ups the default delay by one jiffy for each 256 CPUs that might be on the system (based off of nr_cpu_ids at runtime, -not- NR_CPUS at build time). Updated to collapse #ifdefs for RCU_JIFFIES_TILL_FORCE_QS into a step-function definition as suggested by Josh Triplett. Reported-by: Paul Mackerras Signed-off-by: Paul E. McKenney --- Reading git-format-patch failed