rcu: Remove *_SLOW_* Kconfig options

The RCU_TORTURE_TEST_SLOW_PREINIT, RCU_TORTURE_TEST_SLOW_PREINIT_DELAY,
RCU_TORTURE_TEST_SLOW_PREINIT_DELAY, RCU_TORTURE_TEST_SLOW_INIT,
RCU_TORTURE_TEST_SLOW_INIT_DELAY, RCU_TORTURE_TEST_SLOW_CLEANUP,
and RCU_TORTURE_TEST_SLOW_CLEANUP_DELAY Kconfig options are only
useful for torture testing, and there are the rcutree.gp_cleanup_delay,
rcutree.gp_init_delay, and rcutree.gp_preinit_delay kernel boot parameters
that rcutorture can use instead.  The effect of these parameters is to
artificially slow down grace period initialization and cleanup in order
to make some types of race conditions happen more often.

This commit therefore simplifies Tree RCU a bit by removing the Kconfig
options and adding the corresponding kernel parameters to rcutorture's
.boot files instead.  However, this commit also leaves out the kernel
parameters for TREE02, TREE04, and TREE07 in order to have about the
same number of tests slowed as not slowed.  TREE01, TREE03, TREE05,
and TREE06 are slowed, and the rest are not slowed.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

1 files changed, 0 insertions, 75 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index e4587ebe52c7..960c5d2d3c03 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1373,81 +1373,6 @@ config RCU_TORTURE_TEST
 	  Say M if you want the RCU torture tests to build as a module.
 	  Say N if you are unsure.
 
-config RCU_TORTURE_TEST_SLOW_PREINIT
-	bool "Slow down RCU grace-period pre-initialization to expose races"
-	depends on RCU_TORTURE_TEST
-	help
-	  This option delays grace-period pre-initialization (the
-	  propagation of CPU-hotplug changes up the rcu_node combining
-	  tree) for a few jiffies between initializing each pair of
-	  consecutive rcu_node structures.  This helps to expose races
-	  involving grace-period pre-initialization, in other words, it
-	  makes your kernel less stable.  It can also greatly increase
-	  grace-period latency, especially on systems with large numbers
-	  of CPUs.  This is useful when torture-testing RCU, but in
-	  almost no other circumstance.
-
-	  Say Y here if you want your system to crash and hang more often.
-	  Say N if you want a sane system.
-
-config RCU_TORTURE_TEST_SLOW_PREINIT_DELAY
-	int "How much to slow down RCU grace-period pre-initialization"
-	range 0 5
-	default 3
-	depends on RCU_TORTURE_TEST_SLOW_PREINIT
-	help
-	  This option specifies the number of jiffies to wait between
-	  each rcu_node structure pre-initialization step.
-
-config RCU_TORTURE_TEST_SLOW_INIT
-	bool "Slow down RCU grace-period initialization to expose races"
-	depends on RCU_TORTURE_TEST
-	help
-	  This option delays grace-period initialization for a few
-	  jiffies between initializing each pair of consecutive
-	  rcu_node structures.	This helps to expose races involving
-	  grace-period initialization, in other words, it makes your
-	  kernel less stable.  It can also greatly increase grace-period
-	  latency, especially on systems with large numbers of CPUs.
-	  This is useful when torture-testing RCU, but in almost no
-	  other circumstance.
-
-	  Say Y here if you want your system to crash and hang more often.
-	  Say N if you want a sane system.
-
-config RCU_TORTURE_TEST_SLOW_INIT_DELAY
-	int "How much to slow down RCU grace-period initialization"
-	range 0 5
-	default 3
-	depends on RCU_TORTURE_TEST_SLOW_INIT
-	help
-	  This option specifies the number of jiffies to wait between
-	  each rcu_node structure initialization.
-
-config RCU_TORTURE_TEST_SLOW_CLEANUP
-	bool "Slow down RCU grace-period cleanup to expose races"
-	depends on RCU_TORTURE_TEST
-	help
-	  This option delays grace-period cleanup for a few jiffies
-	  between cleaning up each pair of consecutive rcu_node
-	  structures.  This helps to expose races involving grace-period
-	  cleanup, in other words, it makes your kernel less stable.
-	  It can also greatly increase grace-period latency, especially
-	  on systems with large numbers of CPUs.  This is useful when
-	  torture-testing RCU, but in almost no other circumstance.
-
-	  Say Y here if you want your system to crash and hang more often.
-	  Say N if you want a sane system.
-
-config RCU_TORTURE_TEST_SLOW_CLEANUP_DELAY
-	int "How much to slow down RCU grace-period cleanup"
-	range 0 5
-	default 3
-	depends on RCU_TORTURE_TEST_SLOW_CLEANUP
-	help
-	  This option specifies the number of jiffies to wait between
-	  each rcu_node structure cleanup operation.
-
 config RCU_CPU_STALL_TIMEOUT
 	int "RCU CPU stall timeout in seconds"
 	depends on RCU_STALL_COMMON