lib/stackdepot: rename next_pool_required to new_pool_required

Rename next_pool_required to new_pool_required.

This a purely code readability change: the following patch will change
stack depot to store the pointer to the new pool in a separate variable,
and "new" seems like a more logical name.

Link: https://lkml.kernel.org/r/fd7cd6c6eb250c13ec5d2009d75bb4ddd1470db9.1700502145.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index b3af868627f416a80ddb4c7e13b1ecca5f9e67b8..a38661beab97aff8dcffb3f00e4f2f9009ab7a22 100644 (file)
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -93,12 +93,11 @@ static size_t pool_offset;
 static DEFINE_RAW_SPINLOCK(pool_lock);
 /*
  * Stack depot tries to keep an extra pool allocated even before it runs out
- * of space in the currently used pool.
- * This flag marks that this next extra pool needs to be allocated and
- * initialized. It has the value 0 when either the next pool is not yet
- * initialized or the limit on the number of pools is reached.
+ * of space in the currently used pool. This flag marks whether this extra pool
+ * needs to be allocated. It has the value 0 when either an extra pool is not
+ * yet allocated or if the limit on the number of pools is reached.
  */
-static int next_pool_required = 1;
+static int new_pool_required = 1;
 
 static int __init disable_stack_depot(char *str)
 {
@@ -225,20 +224,20 @@ out_unlock:
 }
 EXPORT_SYMBOL_GPL(stack_depot_init);
 
-/* Keeps the preallocated memory to be used for the next stack depot pool. */
-static void depot_keep_next_pool(void **prealloc)
+/* Keeps the preallocated memory to be used for a new stack depot pool. */
+static void depot_keep_new_pool(void **prealloc)
 {
        /*
-        * If the next pool is already saved or the maximum number of
+        * If a new pool is already saved or the maximum number of
         * pools is reached, do not use the preallocated memory.
-        * Access next_pool_required non-atomically, as there are no concurrent
+        * Access new_pool_required non-atomically, as there are no concurrent
         * write accesses to this variable.
         */
-       if (!next_pool_required)
+       if (!new_pool_required)
                return;
 
        /*
-        * Use the preallocated memory for the next pool
+        * Use the preallocated memory for the new pool
         * as long as we do not exceed the maximum number of pools.
         */
        if (pool_index + 1 < DEPOT_MAX_POOLS) {
@@ -247,13 +246,13 @@ static void depot_keep_next_pool(void **prealloc)
        }
 
        /*
-        * At this point, either the next pool is kept or the maximum
+        * At this point, either a new pool is kept or the maximum
         * number of pools is reached. In either case, take note that
         * keeping another pool is not required.
         * smp_store_release() pairs with smp_load_acquire() in
         * stack_depot_save().
         */
-       smp_store_release(&next_pool_required, 0);
+       smp_store_release(&new_pool_required, 0);
 }
 
 /* Updates references to the current and the next stack depot pools. */
@@ -268,7 +267,7 @@ static bool depot_update_pools(size_t required_size, void **prealloc)
                }
 
                /*
-                * Move on to the next pool.
+                * Move on to the new pool.
                 * WRITE_ONCE() pairs with potential concurrent read in
                 * stack_depot_fetch().
                 */
@@ -277,12 +276,12 @@ static bool depot_update_pools(size_t required_size, void **prealloc)
 
                /*
                 * If the maximum number of pools is not reached, take note
-                * that the next pool needs to be initialized.
+                * that yet another new pool needs to be allocated.
                 * smp_store_release() pairs with smp_load_acquire() in
                 * stack_depot_save().
                 */
                if (pool_index + 1 < DEPOT_MAX_POOLS)
-                       smp_store_release(&next_pool_required, 1);
+                       smp_store_release(&new_pool_required, 1);
        }
 
        /* Check if the current pool is not yet allocated. */
@@ -293,9 +292,9 @@ static bool depot_update_pools(size_t required_size, void **prealloc)
                return true;
        }
 
-       /* Otherwise, try using the preallocated memory for the next pool. */
+       /* Otherwise, try using the preallocated memory for a new pool. */
        if (*prealloc)
-               depot_keep_next_pool(prealloc);
+               depot_keep_new_pool(prealloc);
        return true;
 }
 
@@ -306,7 +305,7 @@ depot_alloc_stack(unsigned long *entries, int size, u32 hash, void **prealloc)
        struct stack_record *stack;
        size_t required_size = DEPOT_STACK_RECORD_SIZE;
 
-       /* Update current and next pools if required and possible. */
+       /* Update current and new pools if required and possible. */
        if (!depot_update_pools(required_size, prealloc))
                return NULL;
 
@@ -438,13 +437,13 @@ depot_stack_handle_t __stack_depot_save(unsigned long *entries,
                goto exit;
 
        /*
-        * Check if another stack pool needs to be initialized. If so, allocate
-        * the memory now - we won't be able to do that under the lock.
+        * Check if another stack pool needs to be allocated. If so, allocate
+        * the memory now: we won't be able to do that under the lock.
         *
         * smp_load_acquire() pairs with smp_store_release() in
-        * depot_update_pools() and depot_keep_next_pool().
+        * depot_update_pools() and depot_keep_new_pool().
         */
-       if (unlikely(can_alloc && smp_load_acquire(&next_pool_required))) {
+       if (unlikely(can_alloc && smp_load_acquire(&new_pool_required))) {
                /*
                 * Zero out zone modifiers, as we don't have specific zone
                 * requirements. Keep the flags related to allocation in atomic
@@ -477,9 +476,9 @@ depot_stack_handle_t __stack_depot_save(unsigned long *entries,
        } else if (prealloc) {
                /*
                 * Stack depot already contains this stack trace, but let's
-                * keep the preallocated memory for the future.
+                * keep the preallocated memory for future.
                 */
-               depot_keep_next_pool(&prealloc);
+               depot_keep_new_pool(&prealloc);
        }
 
        raw_spin_unlock_irqrestore(&pool_lock, flags);