| Message ID | 20230728032232.816584-2-paulmck@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | ec13bc25470a02a9084d90628e1e953a5369109c |
| Headers | show |
| Series | [1/2] torture: Add a kthread-creation callback to _torture_create_kthread() | expand |
On Thu, Jul 27, 2023 at 8:22 PM Paul E. McKenney <paulmck@kernel.org> wrote: > > From: Dietmar Eggemann <dietmar.eggemann@arm.com> > > This commit adds a module parameter that causes the locktorture writer > to run at real-time priority. > > To use it: > insmod /lib/modules/torture.ko random_shuffle=1 > insmod /lib/modules/locktorture.ko torture_type=mutex_lock rt_boost=1 rt_boost_factor=50 nested_locks=3 writer_fifo=1 > ^^^^^^^^^^^^^ > > A predecessor to this patch has been helpful to uncover issues with the > proxy-execution series. > > [ paulmck: Remove locktorture-specific code from kernel/torture.c. ] Thanks again for improving this! I've switched over to your version here in my test tree. Acked-by: John Stultz <jstultz@google.com> thanks -john
On Mon, Aug 07, 2023 at 08:27:29PM -0700, John Stultz wrote: > On Thu, Jul 27, 2023 at 8:22 PM Paul E. McKenney <paulmck@kernel.org> wrote: > > > > From: Dietmar Eggemann <dietmar.eggemann@arm.com> > > > > This commit adds a module parameter that causes the locktorture writer > > to run at real-time priority. > > > > To use it: > > insmod /lib/modules/torture.ko random_shuffle=1 > > insmod /lib/modules/locktorture.ko torture_type=mutex_lock rt_boost=1 rt_boost_factor=50 nested_locks=3 writer_fifo=1 > > ^^^^^^^^^^^^^ > > > > A predecessor to this patch has been helpful to uncover issues with the > > proxy-execution series. > > > > [ paulmck: Remove locktorture-specific code from kernel/torture.c. ] > > Thanks again for improving this! I've switched over to your version > here in my test tree. > > Acked-by: John Stultz <jstultz@google.com> Thank you both! I will apply on my next rebase. Thanx, Paul
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a1457995fd41..7b94455e9ae2 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2918,6 +2918,10 @@ locktorture.torture_type= [KNL] Specify the locking implementation to test. + locktorture.writer_fifo= [KNL] + Run the write-side locktorture kthreads at + sched_set_fifo() real-time priority. + locktorture.verbose= [KNL] Enable additional printk() statements. diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c index 949d3deae506..270c7f80ce84 100644 --- a/kernel/locking/locktorture.c +++ b/kernel/locking/locktorture.c @@ -45,6 +45,7 @@ torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable"); torture_param(int, rt_boost, 2, "Do periodic rt-boost. 0=Disable, 1=Only for rt_mutex, 2=For all lock types."); torture_param(int, rt_boost_factor, 50, "A factor determining how often rt-boost happens."); +torture_param(int, writer_fifo, 0, "Run writers at sched_set_fifo() priority"); torture_param(int, verbose, 1, "Enable verbose debugging printk()s"); torture_param(int, nested_locks, 0, "Number of nested locks (max = 8)"); /* Going much higher trips "BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!" errors */ @@ -809,7 +810,8 @@ static int lock_torture_writer(void *arg) bool skip_main_lock; VERBOSE_TOROUT_STRING("lock_torture_writer task started"); - set_user_nice(current, MAX_NICE); + if (!rt_task(current)) + set_user_nice(current, MAX_NICE); do { if ((torture_random(&rand) & 0xfffff) == 0) @@ -1015,8 +1017,7 @@ static void lock_torture_cleanup(void) if (writer_tasks) { for (i = 0; i < cxt.nrealwriters_stress; i++) - torture_stop_kthread(lock_torture_writer, - writer_tasks[i]); + torture_stop_kthread(lock_torture_writer, writer_tasks[i]); kfree(writer_tasks); writer_tasks = NULL; } @@ -1244,8 +1245,9 @@ static int __init lock_torture_init(void) goto create_reader; /* Create writer. */ - firsterr = torture_create_kthread(lock_torture_writer, &cxt.lwsa[i], - writer_tasks[i]); + firsterr = torture_create_kthread_cb(lock_torture_writer, &cxt.lwsa[i], + writer_tasks[i], + writer_fifo ? sched_set_fifo : NULL); if (torture_init_error(firsterr)) goto unwind; diff --git a/kernel/torture.c b/kernel/torture.c index b88a1a86d9da..a1ac493488e2 100644 --- a/kernel/torture.c +++ b/kernel/torture.c @@ -37,6 +37,7 @@ #include <linux/ktime.h> #include <asm/byteorder.h> #include <linux/torture.h> +#include <linux/sched/rt.h> #include "rcu/rcu.h" MODULE_LICENSE("GPL"); @@ -734,7 +735,7 @@ bool stutter_wait(const char *title) cond_resched_tasks_rcu_qs(); spt = READ_ONCE(stutter_pause_test); for (; spt; spt = READ_ONCE(stutter_pause_test)) { - if (!ret) { + if (!ret && !rt_task(current)) { sched_set_normal(current, MAX_NICE); ret = true; }