linux-kernel - [PATCH 18/21] binder: initialize lru pages in mmap callback

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Message-ID: <20231102185934.773885-19-cmllamas@google.com>
Date:   Thu,  2 Nov 2023 18:59:19 +0000
From:   Carlos Llamas <cmllamas@...gle.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "Arve Hjønnevåg" <arve@...roid.com>,
        Todd Kjos <tkjos@...roid.com>,
        Martijn Coenen <maco@...roid.com>,
        Joel Fernandes <joel@...lfernandes.org>,
        Christian Brauner <brauner@...nel.org>,
        Carlos Llamas <cmllamas@...gle.com>,
        Suren Baghdasaryan <surenb@...gle.com>
Cc:     linux-kernel@...r.kernel.org, kernel-team@...roid.com
Subject: [PATCH 18/21] binder: initialize lru pages in mmap callback

Rather than repeatedly initializing some of the binder_lru_page members
during binder_alloc_new_buf(), perform this initialization just once in
binder_alloc_mmap_handler(), after the pages have been created.

Signed-off-by: Carlos Llamas <cmllamas@...gle.com>
---
 drivers/android/binder_alloc.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index da6c62567ffb..7e0af1786b20 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -278,9 +278,6 @@ static int binder_allocate_page_range(struct binder_alloc *alloc,
 
 		trace_binder_alloc_page_start(alloc, index);
 
-		page->alloc = alloc;
-		INIT_LIST_HEAD(&page->lru);
-
 		ret = binder_get_user_page_remote(alloc, page, page_addr);
 		if (ret) {
 			binder_free_page_range(alloc, start, page_addr);
@@ -791,9 +788,9 @@ void binder_alloc_free_buf(struct binder_alloc *alloc,
 int binder_alloc_mmap_handler(struct binder_alloc *alloc,
 			      struct vm_area_struct *vma)
 {
-	int ret;
-	const char *failure_string;
 	struct binder_buffer *buffer;
+	const char *failure_string;
+	int ret, i;
 
 	if (unlikely(vma->vm_mm != alloc->mm)) {
 		ret = -EINVAL;
@@ -822,6 +819,11 @@ int binder_alloc_mmap_handler(struct binder_alloc *alloc,
 		goto err_alloc_pages_failed;
 	}
 
+	for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
+		alloc->pages[i].alloc = alloc;
+		INIT_LIST_HEAD(&alloc->pages[i].lru);
+	}
+
 	buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 	if (!buffer) {
 		ret = -ENOMEM;
-- 
2.42.0.869.gea05f2083d-goog