UPSTREAM: Revert "binder_alloc: add missing mmap_lock calls when using the VMA"
commit b15655b12ddca7ade09807f790bafb6fab61b50a upstream.
This reverts commit 44e602b4e52f70f04620bbbf4fe46ecb40170bde.
This caused a performance regression particularly when pages are getting
reclaimed. We don't need to acquire the mmap_lock to determine when the
binder buffer has been fully initialized. A subsequent patch will bring
back the lockless approach for this.
[cmllamas: resolved trivial conflicts with renaming of alloc->mm]
Fixes: 44e602b4e52f ("binder_alloc: add missing mmap_lock calls when using the VMA")
Cc: Liam Howlett <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: [email protected]
Change-Id: If26447c08c59fbbc43731ecbd8b501c928ffbe2d
Signed-off-by: Carlos Llamas <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
(cherry picked from commit 7e6b8548549e1fa87fbdd6b54f07b8c37a6d4b5e)
Signed-off-by: Greg Kroah-Hartman <[email protected]>
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index e1620e1..309fa8e 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -381,15 +381,12 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
size_t size, data_offsets_size;
int ret;
- mmap_read_lock(alloc->mm);
if (!binder_alloc_get_vma(alloc)) {
- mmap_read_unlock(alloc->mm);
binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
"%d: binder_alloc_buf, no vma\n",
alloc->pid);
return ERR_PTR(-ESRCH);
}
- mmap_read_unlock(alloc->mm);
data_offsets_size = ALIGN(data_size, sizeof(void *)) +
ALIGN(offsets_size, sizeof(void *));
@@ -918,25 +915,17 @@ void binder_alloc_print_pages(struct seq_file *m,
* Make sure the binder_alloc is fully initialized, otherwise we might
* read inconsistent state.
*/
-
- mmap_read_lock(alloc->mm);
- if (binder_alloc_get_vma(alloc) == NULL) {
- mmap_read_unlock(alloc->mm);
- goto uninitialized;
+ if (binder_alloc_get_vma(alloc) != NULL) {
+ for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
+ page = &alloc->pages[i];
+ if (!page->page_ptr)
+ free++;
+ else if (list_empty(&page->lru))
+ active++;
+ else
+ lru++;
+ }
}
-
- mmap_read_unlock(alloc->mm);
- for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
- page = &alloc->pages[i];
- if (!page->page_ptr)
- free++;
- else if (list_empty(&page->lru))
- active++;
- else
- lru++;
- }
-
-uninitialized:
mutex_unlock(&alloc->mutex);
seq_printf(m, " pages: %d:%d:%d\n", active, lru, free);
seq_printf(m, " pages high watermark: %zu\n", alloc->pages_high);
