locking/locktorture: Fix num reader/writer corner cases

Things can explode for locktorture if the user does combinations
of nwriters_stress=0 nreaders_stress=0. Fix this by not assuming
we always want to torture writer threads.

Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
This commit is contained in:
Davidlohr Bueso 2017-05-15 02:07:23 -07:00 committed by Paul E. McKenney
parent f2f762608f
commit 2ce77d16db

View File

@ -703,8 +703,7 @@ static void __torture_print_stats(char *page,
{
bool fail = 0;
int i, n_stress;
long max = 0;
long min = statp[0].n_lock_acquired;
long max = 0, min = statp ? statp[0].n_lock_acquired : 0;
long long sum = 0;
n_stress = write ? cxt.nrealwriters_stress : cxt.nrealreaders_stress;
@ -811,7 +810,7 @@ static void lock_torture_cleanup(void)
* such, only perform the underlying torture-specific cleanups,
* and avoid anything related to locktorture.
*/
if (!cxt.lwsa)
if (!cxt.lwsa && !cxt.lrsa)
goto end;
if (writer_tasks) {
@ -886,6 +885,13 @@ static int __init lock_torture_init(void)
firsterr = -EINVAL;
goto unwind;
}
if (nwriters_stress == 0 && nreaders_stress == 0) {
pr_alert("lock-torture: must run at least one locking thread\n");
firsterr = -EINVAL;
goto unwind;
}
if (cxt.cur_ops->init)
cxt.cur_ops->init();
@ -909,17 +915,19 @@ static int __init lock_torture_init(void)
#endif
/* Initialize the statistics so that each run gets its own numbers. */
if (nwriters_stress) {
lock_is_write_held = 0;
cxt.lwsa = kmalloc(sizeof(*cxt.lwsa) * cxt.nrealwriters_stress, GFP_KERNEL);
if (cxt.lwsa == NULL) {
VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory");
firsterr = -ENOMEM;
goto unwind;
}
lock_is_write_held = 0;
cxt.lwsa = kmalloc(sizeof(*cxt.lwsa) * cxt.nrealwriters_stress, GFP_KERNEL);
if (cxt.lwsa == NULL) {
VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory");
firsterr = -ENOMEM;
goto unwind;
}
for (i = 0; i < cxt.nrealwriters_stress; i++) {
cxt.lwsa[i].n_lock_fail = 0;
cxt.lwsa[i].n_lock_acquired = 0;
for (i = 0; i < cxt.nrealwriters_stress; i++) {
cxt.lwsa[i].n_lock_fail = 0;
cxt.lwsa[i].n_lock_acquired = 0;
}
}
if (cxt.cur_ops->readlock) {
@ -936,19 +944,21 @@ static int __init lock_torture_init(void)
cxt.nrealreaders_stress = cxt.nrealwriters_stress;
}
lock_is_read_held = 0;
cxt.lrsa = kmalloc(sizeof(*cxt.lrsa) * cxt.nrealreaders_stress, GFP_KERNEL);
if (cxt.lrsa == NULL) {
VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory");
firsterr = -ENOMEM;
kfree(cxt.lwsa);
cxt.lwsa = NULL;
goto unwind;
}
if (nreaders_stress) {
lock_is_read_held = 0;
cxt.lrsa = kmalloc(sizeof(*cxt.lrsa) * cxt.nrealreaders_stress, GFP_KERNEL);
if (cxt.lrsa == NULL) {
VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory");
firsterr = -ENOMEM;
kfree(cxt.lwsa);
cxt.lwsa = NULL;
goto unwind;
}
for (i = 0; i < cxt.nrealreaders_stress; i++) {
cxt.lrsa[i].n_lock_fail = 0;
cxt.lrsa[i].n_lock_acquired = 0;
for (i = 0; i < cxt.nrealreaders_stress; i++) {
cxt.lrsa[i].n_lock_fail = 0;
cxt.lrsa[i].n_lock_acquired = 0;
}
}
}
@ -978,12 +988,14 @@ static int __init lock_torture_init(void)
goto unwind;
}
writer_tasks = kzalloc(cxt.nrealwriters_stress * sizeof(writer_tasks[0]),
GFP_KERNEL);
if (writer_tasks == NULL) {
VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory");
firsterr = -ENOMEM;
goto unwind;
if (nwriters_stress) {
writer_tasks = kzalloc(cxt.nrealwriters_stress * sizeof(writer_tasks[0]),
GFP_KERNEL);
if (writer_tasks == NULL) {
VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory");
firsterr = -ENOMEM;
goto unwind;
}
}
if (cxt.cur_ops->readlock) {