2023-09-13 17:41:43

by andrey.konovalov

Subject: [PATCH v2 09/19] lib/stackdepot: store next pool pointer in new_pool

From: Andrey Konovalov <[email protected]>

Instead of using the last pointer in stack_pools for storing the pointer
to a new pool (which does not yet store any stack records), use a new
new_pool variable.

This a purely code readability change: it seems more logical to store
the pointer to a pool with a special meaning in a dedicated variable.

Signed-off-by: Andrey Konovalov <[email protected]>
---
lib/stackdepot.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index e428f470faf6..81d8733cdbed 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -85,6 +85,8 @@ static unsigned int stack_hash_mask;

/* Array of memory regions that store stack traces. */
static void *stack_pools[DEPOT_MAX_POOLS];
+/* Newly allocated pool that is not yet added to stack_pools. */
+static void *new_pool;
/* Currently used pool in stack_pools. */
static int pool_index;
/* Offset to the unused space in the currently used pool. */
@@ -233,7 +235,7 @@ static void depot_keep_new_pool(void **prealloc)
* as long as we do not exceed the maximum number of pools.
*/
if (pool_index + 1 < DEPOT_MAX_POOLS) {
- stack_pools[pool_index + 1] = *prealloc;
+ new_pool = *prealloc;
*prealloc = NULL;
}

@@ -263,6 +265,8 @@ static bool depot_update_pools(size_t required_size, void **prealloc)
* stack_depot_fetch.
*/
WRITE_ONCE(pool_index, pool_index + 1);
+ stack_pools[pool_index] = new_pool;
+ new_pool = NULL;
pool_offset = 0;

/*
--
2.25.1

2023-09-19 22:32:11

by Alexander Potapenko

Subject: Re: [PATCH v2 09/19] lib/stackdepot: store next pool pointer in new_pool

On Wed, Sep 13, 2023 at 7:15 PM <[email protected]> wrote:
>
> From: Andrey Konovalov <[email protected]>
>
> Instead of using the last pointer in stack_pools for storing the pointer
> to a new pool (which does not yet store any stack records), use a new
> new_pool variable.
>
> This a purely code readability change: it seems more logical to store
> the pointer to a pool with a special meaning in a dedicated variable.
>
> Signed-off-by: Andrey Konovalov <[email protected]>
Reviewed-by: Alexander Potapenko <[email protected]>