Re: [PATCH v2 5/6] maple_tree: Update check_forking() and bench_forking()

[Liam R. Howlett]

* Peng Zhang <zhangpeng.00@xxxxxxxxxxxxx> [230830 08:57]:
> Updated check_forking() and bench_forking() to use __mt_dup() to
> duplicate maple tree. Also increased the number of VMAs, because the
> new way is faster.
> 
> Signed-off-by: Peng Zhang <zhangpeng.00@xxxxxxxxxxxxx>
> ---
>  lib/test_maple_tree.c | 61 +++++++++++++++++++++----------------------
>  1 file changed, 30 insertions(+), 31 deletions(-)
> 
> diff --git a/lib/test_maple_tree.c b/lib/test_maple_tree.c
> index 0ec0c6a7c0b5..72fba7cce148 100644
> --- a/lib/test_maple_tree.c
> +++ b/lib/test_maple_tree.c
> @@ -1837,36 +1837,37 @@ static noinline void __init check_forking(struct maple_tree *mt)
>  {
>  
>  	struct maple_tree newmt;
> -	int i, nr_entries = 134;
> +	int i, nr_entries = 300, ret;

check_forking can probably remain at 134, I set it to to 134 as a
'reasonable' value.  Unless you want 300 to test some specific case in
your case?

>  	void *val;
>  	MA_STATE(mas, mt, 0, 0);
> -	MA_STATE(newmas, mt, 0, 0);
> +	MA_STATE(newmas, &newmt, 0, 0);
> +
> +	mt_init_flags(&newmt, MT_FLAGS_ALLOC_RANGE);
>  
>  	for (i = 0; i <= nr_entries; i++)
>  		mtree_store_range(mt, i*10, i*10 + 5,
>  				  xa_mk_value(i), GFP_KERNEL);
>  
> +
>  	mt_set_non_kernel(99999);
> -	mt_init_flags(&newmt, MT_FLAGS_ALLOC_RANGE);
> -	newmas.tree = &newmt;
> -	mas_reset(&newmas);
> -	mas_reset(&mas);
>  	mas_lock(&newmas);
> -	mas.index = 0;
> -	mas.last = 0;
> -	if (mas_expected_entries(&newmas, nr_entries)) {
> +	mas_lock(&mas);
> +
> +	ret = __mt_dup(mt, &newmt, GFP_NOWAIT | __GFP_NOWARN);
> +	if (ret) {
>  		pr_err("OOM!");
>  		BUG_ON(1);
>  	}
> -	rcu_read_lock();
> -	mas_for_each(&mas, val, ULONG_MAX) {
> -		newmas.index = mas.index;
> -		newmas.last = mas.last;
> +
> +	mas_set(&newmas, 0);
> +	mas_for_each(&newmas, val, ULONG_MAX) {
>  		mas_store(&newmas, val);
>  	}
> -	rcu_read_unlock();
> -	mas_destroy(&newmas);
> +
> +	mas_unlock(&mas);
>  	mas_unlock(&newmas);
> +
> +	mas_destroy(&newmas);
>  	mt_validate(&newmt);
>  	mt_set_non_kernel(0);
>  	mtree_destroy(&newmt);
> @@ -1974,12 +1975,11 @@ static noinline void __init check_mas_store_gfp(struct maple_tree *mt)
>  #if defined(BENCH_FORK)
>  static noinline void __init bench_forking(struct maple_tree *mt)
>  {
> -
>  	struct maple_tree newmt;
> -	int i, nr_entries = 134, nr_fork = 80000;
> +	int i, nr_entries = 300, nr_fork = 80000, ret;
>  	void *val;
>  	MA_STATE(mas, mt, 0, 0);
> -	MA_STATE(newmas, mt, 0, 0);
> +	MA_STATE(newmas, &newmt, 0, 0);
>  
>  	for (i = 0; i <= nr_entries; i++)
>  		mtree_store_range(mt, i*10, i*10 + 5,
> @@ -1988,25 +1988,24 @@ static noinline void __init bench_forking(struct maple_tree *mt)
>  	for (i = 0; i < nr_fork; i++) {
>  		mt_set_non_kernel(99999);
>  		mt_init_flags(&newmt, MT_FLAGS_ALLOC_RANGE);
> -		newmas.tree = &newmt;
> -		mas_reset(&newmas);
> -		mas_reset(&mas);
> -		mas.index = 0;
> -		mas.last = 0;
> -		rcu_read_lock();
> +
>  		mas_lock(&newmas);
> -		if (mas_expected_entries(&newmas, nr_entries)) {
> -			printk("OOM!");
> +		mas_lock(&mas);

Should probably switch this locking to not nest as well, since you have
to make the test framework cope with it already :/


> +		ret = __mt_dup(mt, &newmt, GFP_NOWAIT | __GFP_NOWARN);
> +		if (ret) {
> +			pr_err("OOM!");
>  			BUG_ON(1);
>  		}
> -		mas_for_each(&mas, val, ULONG_MAX) {
> -			newmas.index = mas.index;
> -			newmas.last = mas.last;
> +
> +		mas_set(&newmas, 0);
> +		mas_for_each(&newmas, val, ULONG_MAX) {
>  			mas_store(&newmas, val);
>  		}
> -		mas_destroy(&newmas);
> +
> +		mas_unlock(&mas);
>  		mas_unlock(&newmas);
> -		rcu_read_unlock();
> +
> +		mas_destroy(&newmas);
>  		mt_validate(&newmt);
>  		mt_set_non_kernel(0);
>  		mtree_destroy(&newmt);
> -- 
> 2.20.1
>