Re: [PATCH v2 rcu-dev 1/3] rcuperf: Add ability to increase object allocation size
From: Paul E. McKenney
Date: Tue Mar 17 2020 - 17:08:25 EST
On Mon, Mar 16, 2020 at 12:32:26PM -0400, Joel Fernandes (Google) wrote:
> This allows us to increase memory pressure dynamically using a new
> rcuperf boot command line parameter called 'rcumult'.
>
> Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
Applied for testing and review, thank you!
Thanx, Paul
> ---
>
> The Series v1->v2 only has added a new patch (3/3).
>
>
> kernel/rcu/rcuperf.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/rcu/rcuperf.c b/kernel/rcu/rcuperf.c
> index a4a8d097d84d9..16dd1e6b7c09f 100644
> --- a/kernel/rcu/rcuperf.c
> +++ b/kernel/rcu/rcuperf.c
> @@ -88,6 +88,7 @@ torture_param(bool, shutdown, RCUPERF_SHUTDOWN,
> torture_param(int, verbose, 1, "Enable verbose debugging printk()s");
> torture_param(int, writer_holdoff, 0, "Holdoff (us) between GPs, zero to disable");
> torture_param(int, kfree_rcu_test, 0, "Do we run a kfree_rcu() perf test?");
> +torture_param(int, kfree_mult, 1, "Multiple of kfree_obj size to allocate.");
>
> static char *perf_type = "rcu";
> module_param(perf_type, charp, 0444);
> @@ -635,7 +636,7 @@ kfree_perf_thread(void *arg)
> }
>
> for (i = 0; i < kfree_alloc_num; i++) {
> - alloc_ptr = kmalloc(sizeof(struct kfree_obj), GFP_KERNEL);
> + alloc_ptr = kmalloc(kfree_mult * sizeof(struct kfree_obj), GFP_KERNEL);
> if (!alloc_ptr)
> return -ENOMEM;
>
> @@ -722,6 +723,8 @@ kfree_perf_init(void)
> schedule_timeout_uninterruptible(1);
> }
>
> + pr_alert("kfree object size=%lu\n", kfree_mult * sizeof(struct kfree_obj));
> +
> kfree_reader_tasks = kcalloc(kfree_nrealthreads, sizeof(kfree_reader_tasks[0]),
> GFP_KERNEL);
> if (kfree_reader_tasks == NULL) {
> --
> 2.25.1.481.gfbce0eb801-goog