Commit Graph

18 Commits

Author SHA1 Message Date
Paul E. McKenney
f881825a73 rcutorture: Gracefully handle NULL cleanup hooks
Although most torture tests will have some cleanup hook, it is possible
that one might not.  This commit therefore enables graceful handling of
a NULL cleanup hook during torture-test shutdown.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:04:39 -08:00
Paul E. McKenney
bfefc73aa1 rcutorture: Stop generic kthreads in torture_cleanup()
The specific torture modules (like rcutorture) need to call
torture_cleanup() in any case, so this commit makes torture_cleanup()
deal with torture_shutdown_cleanup() and torture_stutter_cleanup() so
that the specific modules don't have to deal with these details.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:04:27 -08:00
Paul E. McKenney
9c029b8609 rcutorture: Abstract torture_stop_kthread()
Stopping of kthreads is not RCU-specific, so this commit abstracts
out torture_stop_kthread(), saving a few lines of code in the process.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:04:25 -08:00
Paul E. McKenney
47cf29b9e7 rcutorture: Abstract torture_create_kthread()
Creation of kthreads is not RCU-specific, so this commit abstracts
out torture_create_kthread(), saving a few tens of lines of code in
the process.

This change requires modifying VERBOSE_TOROUT_ERRSTRING() to take a
non-const string, so that _torture_create_kthread() can avoid an
open-coded substitute.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:03:24 -08:00
Paul E. McKenney
7fafaac5b9 rcutorture: Fix rcutorture shutdown races
Not all of the rcutorture kthreads waited for kthread_should_stop()
before returning from their top-level functions, and none of them
used torture_shutdown_absorb() properly.  These problems can result in
segfaults and hangs at shutdown time, and some recent changes perturbed
timing sufficiently to make them much more probable.  This commit
therefore creates a torture_kthread_stopping() function that does the
proper kthread shutdown dance in one centralized location.

Accommodate this grouping by making VERBOSE_TOROUT_STRING() capable of
taking a non-const string as its argument, which allows the new
torture_kthread_stopping() to pass its "title" argument directly to
the updated version of VERBOSE_TOROUT_STRING().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-02-23 09:03:21 -08:00
Paul E. McKenney
14562d1cf1 rcutorture: Announce task creation
A few "stealth-start rcutorture kthreads" have accumulated over the years,
so this commit adds console-log announcements (but only if the torture
tests are running verbose).

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:03:20 -08:00
Paul E. McKenney
e991dbc077 rcutorture: Abstract torture_shutdown()
Because auto-shutdown of torture testing is not specific to RCU,
this commit moves the auto-shutdown function to kernel/torture.c.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:03:18 -08:00
Paul E. McKenney
57a2fe90fc rcutorture: Apply ACCESS_ONCE() to racy fullstop accesses
Because the fullstop variable can be accessed while it is being updated,
this commit avoids any resulting compiler mischief through use of
ACCESS_ONCE() for non-initialization accesses to this shared variable.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:03:16 -08:00
Paul E. McKenney
628edaa506 rcutorture: Abstract stutter_wait()
Because stuttering the test load (stopping and restarting it) is useful
for non-RCU testing, this commit moves the load-stuttering functionality
to kernel/torture.c.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:02:54 -08:00
Paul E. McKenney
fac480efcb rcutorture: Add diagnostic for unscheduled system shutdown
Currently, rcutorture can terminate via rmmod, via self-shutdown,
via something else shutting the system down, or of course the usual
catastrophic termination.  The first two get flagged, so this commit adds
a message for the third.  For the fourth, your warranty is void as always.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:01:13 -08:00
Paul E. McKenney
36970bb91d rcutorture: Privatize fullstop
This commit introduces the torture_must_stop() function in order to
keep use of the fullstop variable local to kernel/torture.c.  There
is also a torture_must_stop_irq() counterpart for use from RCU callbacks,
timeout handlers, and the like.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:01:12 -08:00
Paul E. McKenney
4622b487ec rcutorture: Abstract torture_shutdown_notify()
Because handling the race between rmmod and system shutdown is not
specific to RCU, this commit abstracts torture_shutdown_notify(),
placing this code into kernel/torture.c.  This change also allows
fullstop_mutex to be private to kernel/torture.c.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:01:11 -08:00
Paul E. McKenney
cc47ae0830 rcutorture: Abstract torture-test cleanup
This commit creates a torture_cleanup() that handles the generic
cleanup actions local to kernel/torture.c.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:01:08 -08:00
Paul E. McKenney
b5daa8f3b3 rcutorture: Abstract torture-test initialization
This commit creates torture_init_begin() and torture_init_end() functions
to abstract locking and allow the torture_type and verbose variables
in kernel/torture.o to become static.  With a bit more abstraction,
fullstop_mutex will also become static.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:01:07 -08:00
Paul E. McKenney
2e9e8081d2 rcutorture: Abstract torture_onoff()
Because online/offline torturing is not specific to RCU, this commit
abstracts it into the kernel/torture.c module to allow other torture
tests to use it.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:01:06 -08:00
Paul E. McKenney
3808dc9fab rcutorture: Abstract torture_shuffle()
The torture_shuffle() function forces each CPU in turn to go idle
periodically in order to check for problems interacting with per-CPU
variables and with dyntick-idle mode.  Because this sort of debugging
is not specific to RCU, this commit abstracts that functionality.
This in turn requires abstracting some additional infrastructure.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-02-23 09:01:05 -08:00
Paul E. McKenney
f67a33561e rcutorture: Abstract torture_shutdown_absorb()
Because handling races between rmmod and normal shutdown is not specific
to rcutorture, this commit renames rcutorture_shutdown_absorb() to
torture_shutdown_absorb() and pulls it out into then kernel/torture.c
module.  This implies pulling the fullstop mechanism into kernel/torture.c
as well.

The exporting of fullstop and fullstop_mutex is ugly and must die.
And it does in fact die in later commits that introduce higher-level
APIs that encapsulate both of these variables.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>`
2014-02-23 09:01:04 -08:00
Paul E. McKenney
51b1130eb5 rcutorture: Abstract rcu_torture_random()
Because rcu_torture_random() will be used by the locking equivalent to
rcutorture, pull it out into its own module.  This new module cannot
be separately configured, instead, use the Kconfig "select" statement
from the Kconfig options of tests depending on it.

Suggested-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-02-23 09:00:58 -08:00