linux-toradex.git/kernel/rcutorture.c, branch v3.4.73

PTR_ERR should be called before its argument is cleared.

2012-02-21T17:06:10+00:00

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// 
@@
expression e,e1;
constant c;
@@

*e = c
... when != e = e1
    when != &e
    when != true IS_ERR(e)
*PTR_ERR(e)
// 

Signed-off-by: Julia Lawall 
Reported-by: Josh Triplett 
Signed-off-by: Paul E. McKenney

rcu: Trace only after NULL-pointer check

2012-02-21T17:06:09+00:00

Fix a bonehead error introduced when adding event tracing to rcutorture.
Move the traces to follow the NULL-pointer checks.

Signed-off-by: Paul E. McKenney

rcu: Add CPU-stall capability to rcutorture

2012-02-21T17:03:52+00:00

Add module parameters to rcutorture that induce a CPU stall.
The stall_cpu parameter specifies how long to stall in seconds,
defaulting to zero, which indicates no stalling is to be undertaken.
The stall_cpu_holdoff parameter specifies how many seconds after
insmod (or boot, if rcutorture is built into the kernel) that this
stall is to start.  The default value for stall_cpu_holdoff is ten
seconds.

Signed-off-by: Paul E. McKenney 
Signed-off-by: Paul E. McKenney

rcutorture: Permit holding off CPU-hotplug operations during boot

2012-02-21T17:03:50+00:00

When rcutorture is started automatically at boot time, it might well
also start CPU-hotplug operations at that time, which might not be
desirable.  This commit therefore adds an rcutorture parameter that
allows CPU-hotplug operations to be held off for the specified number
of seconds after the start of boot.

Signed-off-by: Paul E. McKenney 
Signed-off-by: Paul E. McKenney

rcu: Make rcutorture flag online/offline failures

2012-02-21T17:03:35+00:00

Make rcutorture check for CPU-hotplug failures and complain if there
were any.

Signed-off-by: Paul E. McKenney 
Signed-off-by: Paul E. McKenney

rcu: Add missing __cpuinit annotation in rcutorture code

2012-01-16T17:44:05+00:00

"rcu: Add rcutorture CPU-hotplug capability" adds cpu hotplug operations
to the rcutorture code but produces a false positive warning about section
mismatches:

WARNING: vmlinux.o(.text+0x1e420c): Section mismatch in reference from the
	 function rcu_torture_onoff() to the function .cpuinit.text:cpu_up()
	 The function rcu_torture_onoff() references
	 the function __cpuinit cpu_up().
	 This is often because rcu_torture_onoff lacks a __cpuinit
	 annotation or the annotation of cpu_up is wrong.

This commit therefore adds a __cpuinit annotation so the warning goes away.

Signed-off-by: Heiko Carstens 
Signed-off-by: Paul E. McKenney

rcu: Make rcutorture bool parameters really bool (core code)

2012-01-16T17:43:56+00:00

module_param(bool) used to counter-intuitively take an int.  In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.

It's time to remove the int/unsigned int option.  For this version
it'll simply give a warning, but it'll break next kernel version.
This commit makes this change to rcutorture.

Signed-off-by: Rusty Russell 
Signed-off-by: Paul E. McKenney

rcu: Add rcutorture tests for srcu_read_lock_raw()

2011-12-11T18:32:21+00:00

This commit adds simple rcutorture tests for srcu_read_lock_raw() and
srcu_read_unlock_raw().  It does not test doing srcu_read_lock_raw()
in an exception handler and releasing it in the corresponding process
context.

Signed-off-by: Paul E. McKenney

rcu: Make rcutorture test for hotpluggability before offlining CPUs

2011-12-11T18:32:21+00:00

The rcutorture test now can automatically exercise CPU hotplug and
collect success statistics, which can be correlated with other rcutorture
activity.  This permits rcutorture to completely exercise RCU regardless
of what sort of userspace and filesystem layout is in use.  Unfortunately,
rcutorture is happy to attempt to offline CPUs that cannot be offlined,
for example, CPU 0 in both the x86 and ARM architectures.  Although this
allows rcutorture testing to proceed normally, it confounds attempts at
error analysis due to the resulting flood of spurious CPU-hotplug errors.

Therefore, this commit uses the new cpu_is_hotpluggable() function to
avoid attempting to offline CPUs that are not hotpluggable, which in
turn avoids spurious CPU-hotplug errors.

Signed-off-by: Paul E. McKenney 
Signed-off-by: Paul E. McKenney

rcu: Add rcutorture CPU-hotplug capability

2011-12-11T18:31:56+00:00

Running CPU-hotplug operations concurrently with rcutorture has
historically been a good way to find bugs in both RCU and CPU hotplug.
This commit therefore adds an rcutorture module parameter called
"onoff_interval" that causes a randomly selected CPU-hotplug operation to
be executed at the specified interval, in seconds.  The default value of
"onoff_interval" is zero, which disables rcutorture-instigated CPU-hotplug
operations.

Signed-off-by: Paul E. McKenney 
Signed-off-by: Paul E. McKenney