[PATCH 13/21] binder: relocate low space calculation

From: Carlos Llamas
Date: Thu Nov 02 2023 - 15:01:45 EST


Move the low async space calculation to debug_low_async_space_locked().
This logic not only fits better here but also offloads some of the many
tasks currently done in binder_alloc_new_buf_locked().

No functional change in this patch.

Signed-off-by: Carlos Llamas <cmllamas@xxxxxxxxxx>
---
drivers/android/binder_alloc.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index 3fe5c734c3df..cc627c106a01 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -375,6 +375,15 @@ static bool debug_low_async_space_locked(struct binder_alloc *alloc)
size_t num_buffers = 0;
struct rb_node *n;

+ /*
+ * Only start detecting spammers once we have less than 20% of async
+ * space left (which is less than 10% of total buffer size).
+ */
+ if (alloc->free_async_space >= alloc->buffer_size / 10) {
+ alloc->oneway_spam_detected = false;
+ return false;
+ }
+
for (n = rb_first(&alloc->allocated_buffers); n != NULL;
n = rb_next(n)) {
buffer = rb_entry(n, struct binder_buffer, rb_node);
@@ -497,16 +506,8 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC,
"%d: binder_alloc_buf size %zd async free %zd\n",
alloc->pid, size, alloc->free_async_space);
- if (alloc->free_async_space < alloc->buffer_size / 10) {
- /*
- * Start detecting spammers once we have less than 20%
- * of async space left (which is less than 10% of total
- * buffer size).
- */
- buffer->oneway_spam_suspect = debug_low_async_space_locked(alloc);
- } else {
- alloc->oneway_spam_detected = false;
- }
+ if (debug_low_async_space_locked(alloc))
+ buffer->oneway_spam_suspect = true;
}

return buffer;
--
2.42.0.869.gea05f2083d-goog