[09/18] lib/stackdepot: rename hash table constants and variables
Commit Message
From: Andrey Konovalov <andreyknvl@google.com>
Give more meaningful names to hash table-related constants and variables:
1. Rename STACK_HASH_SCALE to STACK_TABLE_SCALE to point out that it is
related to scaling the hash table.
2. Rename STACK_HASH_ORDER_MIN/MAX to STACK_BUCKET_NUMBER_ORDER_MIN/MAX
to point out that it is related to the number of hash table buckets.
3. Rename stack_hash_order to stack_bucket_number_order for the same
reason as #2.
No functional changes.
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
lib/stackdepot.c | 42 +++++++++++++++++++++---------------------
1 file changed, 21 insertions(+), 21 deletions(-)
Comments
On Mon, Jan 30, 2023 at 9:50 PM <andrey.konovalov@linux.dev> wrote:
>
> From: Andrey Konovalov <andreyknvl@google.com>
>
> Give more meaningful names to hash table-related constants and variables:
>
> 1. Rename STACK_HASH_SCALE to STACK_TABLE_SCALE to point out that it is
> related to scaling the hash table.
It's only used twice, and in short lines, maybe make it
STACK_HASH_TABLE_SCALE to point that out? :)
> 2. Rename STACK_HASH_ORDER_MIN/MAX to STACK_BUCKET_NUMBER_ORDER_MIN/MAX
> to point out that it is related to the number of hash table buckets.
How about DEPOT_BUCKET_... or STACKDEPOT_BUCKET_...?
(just bikeshedding, I don't have any strong preference).
> 3. Rename stack_hash_order to stack_bucket_number_order for the same
> reason as #2.
>
> No functional changes.
>
> Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
On Tue, Jan 31, 2023 at 12:34 PM Alexander Potapenko <glider@google.com> wrote:
>
> On Mon, Jan 30, 2023 at 9:50 PM <andrey.konovalov@linux.dev> wrote:
> >
> > From: Andrey Konovalov <andreyknvl@google.com>
> >
> > Give more meaningful names to hash table-related constants and variables:
> >
> > 1. Rename STACK_HASH_SCALE to STACK_TABLE_SCALE to point out that it is
> > related to scaling the hash table.
>
> It's only used twice, and in short lines, maybe make it
> STACK_HASH_TABLE_SCALE to point that out? :)
Sure, sounds good :)
> > 2. Rename STACK_HASH_ORDER_MIN/MAX to STACK_BUCKET_NUMBER_ORDER_MIN/MAX
> > to point out that it is related to the number of hash table buckets.
>
> How about DEPOT_BUCKET_... or STACKDEPOT_BUCKET_...?
> (just bikeshedding, I don't have any strong preference).
This is what I had initially actually but then decided to keep the
prefix as STACK_ to match the stack_slabs and stack_table variables.
However, I can also rename those variables to depot_slabs and
depot_table. Do you think it makes sense?
On Tue, Jan 31, 2023 at 8:02 PM Andrey Konovalov <andreyknvl@gmail.com> wrote:
>
> On Tue, Jan 31, 2023 at 12:34 PM Alexander Potapenko <glider@google.com> wrote:
> >
> > On Mon, Jan 30, 2023 at 9:50 PM <andrey.konovalov@linux.dev> wrote:
> > >
> > > From: Andrey Konovalov <andreyknvl@google.com>
> > >
> > > Give more meaningful names to hash table-related constants and variables:
> > >
> > > 1. Rename STACK_HASH_SCALE to STACK_TABLE_SCALE to point out that it is
> > > related to scaling the hash table.
> >
> > It's only used twice, and in short lines, maybe make it
> > STACK_HASH_TABLE_SCALE to point that out? :)
>
> Sure, sounds good :)
>
> > > 2. Rename STACK_HASH_ORDER_MIN/MAX to STACK_BUCKET_NUMBER_ORDER_MIN/MAX
> > > to point out that it is related to the number of hash table buckets.
> >
> > How about DEPOT_BUCKET_... or STACKDEPOT_BUCKET_...?
> > (just bikeshedding, I don't have any strong preference).
>
> This is what I had initially actually but then decided to keep the
> prefix as STACK_ to match the stack_slabs and stack_table variables.
Ok, let's keep your version then.
Thanks!
@@ -76,17 +76,17 @@ static bool __stack_depot_early_init_requested __initdata = IS_ENABLED(CONFIG_ST
static bool __stack_depot_early_init_passed __initdata;
/* Use one hash table bucket per 16 KB of memory. */
-#define STACK_HASH_SCALE 14
+#define STACK_TABLE_SCALE 14
/* Limit the number of buckets between 4K and 1M. */
-#define STACK_HASH_ORDER_MIN 12
-#define STACK_HASH_ORDER_MAX 20
+#define STACK_BUCKET_NUMBER_ORDER_MIN 12
+#define STACK_BUCKET_NUMBER_ORDER_MAX 20
/* Initial seed for jhash2. */
#define STACK_HASH_SEED 0x9747b28c
/* Hash table of pointers to stored stack traces. */
static struct stack_record **stack_table;
/* Fixed order of the number of table buckets. Used when KASAN is enabled. */
-static unsigned int stack_hash_order;
+static unsigned int stack_bucket_number_order;
/* Hash mask for indexing the table. */
static unsigned int stack_hash_mask;
@@ -137,28 +137,28 @@ int __init stack_depot_early_init(void)
* in fuzzing scenarios, which leads to a large number of different
* stack traces being stored in stack depot.
*/
- if (kasan_enabled() && !stack_hash_order)
- stack_hash_order = STACK_HASH_ORDER_MAX;
+ if (kasan_enabled() && !stack_bucket_number_order)
+ stack_bucket_number_order = STACK_BUCKET_NUMBER_ORDER_MAX;
if (!__stack_depot_early_init_requested || stack_depot_disabled)
return 0;
/*
- * If stack_hash_order is not set, leave entries as 0 to rely on the
- * automatic calculations performed by alloc_large_system_hash.
+ * If stack_bucket_number_order is not set, leave entries as 0 to rely
+ * on the automatic calculations performed by alloc_large_system_hash.
*/
- if (stack_hash_order)
- entries = 1UL << stack_hash_order;
+ if (stack_bucket_number_order)
+ entries = 1UL << stack_bucket_number_order;
pr_info("allocating hash table via alloc_large_system_hash\n");
stack_table = alloc_large_system_hash("stackdepot",
sizeof(struct stack_record *),
entries,
- STACK_HASH_SCALE,
+ STACK_TABLE_SCALE,
HASH_EARLY | HASH_ZERO,
NULL,
&stack_hash_mask,
- 1UL << STACK_HASH_ORDER_MIN,
- 1UL << STACK_HASH_ORDER_MAX);
+ 1UL << STACK_BUCKET_NUMBER_ORDER_MIN,
+ 1UL << STACK_BUCKET_NUMBER_ORDER_MAX);
if (!stack_table) {
pr_err("hash table allocation failed, disabling\n");
stack_depot_disabled = true;
@@ -181,13 +181,13 @@ int stack_depot_init(void)
goto out_unlock;
/*
- * Similarly to stack_depot_early_init, use stack_hash_order
+ * Similarly to stack_depot_early_init, use stack_bucket_number_order
* if assigned, and rely on automatic scaling otherwise.
*/
- if (stack_hash_order) {
- entries = 1UL << stack_hash_order;
+ if (stack_bucket_number_order) {
+ entries = 1UL << stack_bucket_number_order;
} else {
- int scale = STACK_HASH_SCALE;
+ int scale = STACK_TABLE_SCALE;
entries = nr_free_buffer_pages();
entries = roundup_pow_of_two(entries);
@@ -198,10 +198,10 @@ int stack_depot_init(void)
entries <<= (PAGE_SHIFT - scale);
}
- if (entries < 1UL << STACK_HASH_ORDER_MIN)
- entries = 1UL << STACK_HASH_ORDER_MIN;
- if (entries > 1UL << STACK_HASH_ORDER_MAX)
- entries = 1UL << STACK_HASH_ORDER_MAX;
+ if (entries < 1UL << STACK_BUCKET_NUMBER_ORDER_MIN)
+ entries = 1UL << STACK_BUCKET_NUMBER_ORDER_MIN;
+ if (entries > 1UL << STACK_BUCKET_NUMBER_ORDER_MAX)
+ entries = 1UL << STACK_BUCKET_NUMBER_ORDER_MAX;
pr_info("allocating hash table of %lu entries via kvcalloc\n", entries);
stack_table = kvcalloc(entries, sizeof(struct stack_record *), GFP_KERNEL);