Re: [PATCH-next 2/5] lib/test_vmalloc.c: add a new 'nr_threads' parameter
On Mon, Apr 05, 2021 at 07:39:20PM -0700, Andrew Morton wrote:
> On Sat, 3 Apr 2021 14:31:43 +0200 Uladzislau Rezki wrote:
>
> > >
> > > We may need to replaced that kcalloc() with kmvalloc() though...
> > >
> > Yep. If we limit to USHRT_MAX, the maximum amount of memory for
> > internal data would be ~12MB. Something like below:
> >
> > diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c
> > index d337985e4c5e..a5103e3461bf 100644
> > --- a/lib/test_vmalloc.c
> > +++ b/lib/test_vmalloc.c
> > @@ -24,7 +24,7 @@
> > MODULE_PARM_DESC(name, msg) \
> >
> > __param(int, nr_threads, 0,
> > - "Number of workers to perform tests(min: 1 max: 1024)");
> > + "Number of workers to perform tests(min: 1 max: 65536)");
> >
> > __param(bool, sequential_test_order, false,
> > "Use sequential stress tests order");
> > @@ -469,13 +469,13 @@ init_test_configurtion(void)
> > {
> > /*
> > * A maximum number of workers is defined as hard-coded
> > -* value and set to 1024. We add such gap just in case
> > +* value and set to 65536. We add such gap just in case
> > * and for potential heavy stressing.
> > */
> > - nr_threads = clamp(nr_threads, 1, 1024);
> > + nr_threads = clamp(nr_threads, 1, 65536);
> >
> > /* Allocate the space for test instances. */
> > - tdriver = kcalloc(nr_threads, sizeof(*tdriver), GFP_KERNEL);
> > + tdriver = kvcalloc(nr_threads, sizeof(*tdriver), GFP_KERNEL);
> > if (tdriver == NULL)
> > return -1;
> >
> > @@ -555,7 +555,7 @@ static void do_concurrent_test(void)
> > i, t->stop - t->start);
> > }
> >
> > - kfree(tdriver);
> > + kvfree(tdriver);
> > }
> >
> > static int vmalloc_test_init(void)
> >
> > Does it sound reasonable for you?
>
> I think so. It's a test thing so let's give testers more flexibility,
> remembering that they don't need as much protection from their own
> mistakes.
>
OK. I will send one more extra patch then.
--
Vlad Rezki
Re: [PATCH-next 2/5] lib/test_vmalloc.c: add a new 'nr_threads' parameter
On Sat, 3 Apr 2021 14:31:43 +0200 Uladzislau Rezki wrote:
> >
> > We may need to replaced that kcalloc() with kmvalloc() though...
> >
> Yep. If we limit to USHRT_MAX, the maximum amount of memory for
> internal data would be ~12MB. Something like below:
>
> diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c
> index d337985e4c5e..a5103e3461bf 100644
> --- a/lib/test_vmalloc.c
> +++ b/lib/test_vmalloc.c
> @@ -24,7 +24,7 @@
> MODULE_PARM_DESC(name, msg) \
>
> __param(int, nr_threads, 0,
> - "Number of workers to perform tests(min: 1 max: 1024)");
> + "Number of workers to perform tests(min: 1 max: 65536)");
>
> __param(bool, sequential_test_order, false,
> "Use sequential stress tests order");
> @@ -469,13 +469,13 @@ init_test_configurtion(void)
> {
> /*
> * A maximum number of workers is defined as hard-coded
> -* value and set to 1024. We add such gap just in case
> +* value and set to 65536. We add such gap just in case
> * and for potential heavy stressing.
> */
> - nr_threads = clamp(nr_threads, 1, 1024);
> + nr_threads = clamp(nr_threads, 1, 65536);
>
> /* Allocate the space for test instances. */
> - tdriver = kcalloc(nr_threads, sizeof(*tdriver), GFP_KERNEL);
> + tdriver = kvcalloc(nr_threads, sizeof(*tdriver), GFP_KERNEL);
> if (tdriver == NULL)
> return -1;
>
> @@ -555,7 +555,7 @@ static void do_concurrent_test(void)
> i, t->stop - t->start);
> }
>
> - kfree(tdriver);
> + kvfree(tdriver);
> }
>
> static int vmalloc_test_init(void)
>
> Does it sound reasonable for you?
I think so. It's a test thing so let's give testers more flexibility,
remembering that they don't need as much protection from their own
mistakes.
Re: [PATCH-next 2/5] lib/test_vmalloc.c: add a new 'nr_threads' parameter
> On Fri, 2 Apr 2021 22:22:34 +0200 "Uladzislau Rezki (Sony)"
> wrote:
>
> > By using this parameter we can specify how many workers are
> > created to perform vmalloc tests. By default it is one CPU.
> > The maximum value is set to 1024.
> >
> > As a result of this change a 'single_cpu_test' one becomes
> > obsolete, therefore it is no longer needed.
> >
>
> Why limit to 1024? Maybe testers want more - what's the downside to
> permitting that?
>
I was thinking mainly about if a tester issues enormous number of kthreads,
so a system is not able to handle it. Therefore i clamped that value to 1024.
>From the other hand we can give more wide permissions, in that case a
user should think more carefully about what is passed. For example we
can limit max value by USHRT_MAX what is 65536.
>
> We may need to replaced that kcalloc() with kmvalloc() though...
>
Yep. If we limit to USHRT_MAX, the maximum amount of memory for
internal data would be ~12MB. Something like below:
diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c
index d337985e4c5e..a5103e3461bf 100644
--- a/lib/test_vmalloc.c
+++ b/lib/test_vmalloc.c
@@ -24,7 +24,7 @@
MODULE_PARM_DESC(name, msg) \
__param(int, nr_threads, 0,
- "Number of workers to perform tests(min: 1 max: 1024)");
+ "Number of workers to perform tests(min: 1 max: 65536)");
__param(bool, sequential_test_order, false,
"Use sequential stress tests order");
@@ -469,13 +469,13 @@ init_test_configurtion(void)
{
/*
* A maximum number of workers is defined as hard-coded
-* value and set to 1024. We add such gap just in case
+* value and set to 65536. We add such gap just in case
* and for potential heavy stressing.
*/
- nr_threads = clamp(nr_threads, 1, 1024);
+ nr_threads = clamp(nr_threads, 1, 65536);
/* Allocate the space for test instances. */
- tdriver = kcalloc(nr_threads, sizeof(*tdriver), GFP_KERNEL);
+ tdriver = kvcalloc(nr_threads, sizeof(*tdriver), GFP_KERNEL);
if (tdriver == NULL)
return -1;
@@ -555,7 +555,7 @@ static void do_concurrent_test(void)
i, t->stop - t->start);
}
- kfree(tdriver);
+ kvfree(tdriver);
}
static int vmalloc_test_init(void)
Does it sound reasonable for you?
--
Vlad Rezki
Re: [PATCH-next 2/5] lib/test_vmalloc.c: add a new 'nr_threads' parameter
On Fri, 2 Apr 2021 22:22:34 +0200 "Uladzislau Rezki (Sony)" wrote: > By using this parameter we can specify how many workers are > created to perform vmalloc tests. By default it is one CPU. > The maximum value is set to 1024. > > As a result of this change a 'single_cpu_test' one becomes > obsolete, therefore it is no longer needed. > Why limit to 1024? Maybe testers want more - what's the downside to permitting that? We may need to replaced that kcalloc() with kmvalloc() though...
[PATCH-next 2/5] lib/test_vmalloc.c: add a new 'nr_threads' parameter
By using this parameter we can specify how many workers are
created to perform vmalloc tests. By default it is one CPU.
The maximum value is set to 1024.
As a result of this change a 'single_cpu_test' one becomes
obsolete, therefore it is no longer needed.
Signed-off-by: Uladzislau Rezki (Sony)
---
lib/test_vmalloc.c | 88 +-
1 file changed, 40 insertions(+), 48 deletions(-)
diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c
index 4eb6abdaa74e..d337985e4c5e 100644
--- a/lib/test_vmalloc.c
+++ b/lib/test_vmalloc.c
@@ -23,8 +23,8 @@
module_param(name, type, 0444); \
MODULE_PARM_DESC(name, msg) \
-__param(bool, single_cpu_test, false,
- "Use single first online CPU to run tests");
+__param(int, nr_threads, 0,
+ "Number of workers to perform tests(min: 1 max: 1024)");
__param(bool, sequential_test_order, false,
"Use sequential stress tests order");
@@ -50,13 +50,6 @@ __param(int, run_test_mask, INT_MAX,
/* Add a new test case description here. */
);
-/*
- * Depends on single_cpu_test parameter. If it is true, then
- * use first online CPU to trigger a test on, otherwise go with
- * all online CPUs.
- */
-static cpumask_t cpus_run_test_mask = CPU_MASK_NONE;
-
/*
* Read write semaphore for synchronization of setup
* phase that is done in main thread and workers.
@@ -386,16 +379,13 @@ struct test_case_data {
u64 time;
};
-/* Split it to get rid of: WARNING: line over 80 characters */
-static struct test_case_data
- per_cpu_test_data[NR_CPUS][ARRAY_SIZE(test_case_array)];
-
static struct test_driver {
struct task_struct *task;
+ struct test_case_data data[ARRAY_SIZE(test_case_array)];
+
unsigned long start;
unsigned long stop;
- int cpu;
-} per_cpu_test_driver[NR_CPUS];
+} *tdriver;
static void shuffle_array(int *arr, int n)
{
@@ -423,9 +413,6 @@ static int test_func(void *private)
ktime_t kt;
u64 delta;
- if (set_cpus_allowed_ptr(current, cpumask_of(t->cpu)) < 0)
- pr_err("Failed to set affinity to %d CPU\n", t->cpu);
-
for (i = 0; i < ARRAY_SIZE(test_case_array); i++)
random_array[i] = i;
@@ -450,9 +437,9 @@ static int test_func(void *private)
kt = ktime_get();
for (j = 0; j < test_repeat_count; j++) {
if (!test_case_array[index].test_func())
- per_cpu_test_data[t->cpu][index].test_passed++;
+ t->data[index].test_passed++;
else
- per_cpu_test_data[t->cpu][index].test_failed++;
+ t->data[index].test_failed++;
}
/*
@@ -461,7 +448,7 @@ static int test_func(void *private)
delta = (u64) ktime_us_delta(ktime_get(), kt);
do_div(delta, (u32) test_repeat_count);
- per_cpu_test_data[t->cpu][index].time = delta;
+ t->data[index].time = delta;
}
t->stop = get_cycles();
@@ -477,53 +464,56 @@ static int test_func(void *private)
return 0;
}
-static void
+static int
init_test_configurtion(void)
{
/*
-* Reset all data of all CPUs.
+* A maximum number of workers is defined as hard-coded
+* value and set to 1024. We add such gap just in case
+* and for potential heavy stressing.
*/
- memset(per_cpu_test_data, 0, sizeof(per_cpu_test_data));
+ nr_threads = clamp(nr_threads, 1, 1024);
- if (single_cpu_test)
- cpumask_set_cpu(cpumask_first(cpu_online_mask),
- _run_test_mask);
- else
- cpumask_and(_run_test_mask, cpu_online_mask,
- cpu_online_mask);
+ /* Allocate the space for test instances. */
+ tdriver = kcalloc(nr_threads, sizeof(*tdriver), GFP_KERNEL);
+ if (tdriver == NULL)
+ return -1;
if (test_repeat_count <= 0)
test_repeat_count = 1;
if (test_loop_count <= 0)
test_loop_count = 1;
+
+ return 0;
}
static void do_concurrent_test(void)
{
- int cpu, ret;
+ int i, ret;
/*
* Set some basic configurations plus sanity check.
*/
- init_test_configurtion();
+ ret = init_test_configurtion();
+ if (ret < 0)
+ return;
/*
* Put on hold all workers.
*/
down_write(_for_test_rwsem);
- for_each_cpu(cpu, _run_test_mask) {
- struct test_driver *t = _cpu_test_driver[cpu];
+ for (i = 0; i < nr_threads; i++) {
+ struct test_driver *t = [i];
- t->cpu = cpu;
- t->task = kthread_run(test_func, t, "vmalloc_test/%d", cpu);
+
