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Date:   Fri,  1 Dec 2023 17:21:41 +0000
In-Reply-To: <20231201172212.1813387-1-cmllamas@google.com>
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Message-ID: <20231201172212.1813387-13-cmllamas@google.com>
Subject: [PATCH v2 12/28] binder: remove pid param in binder_alloc_new_buf()
From:   Carlos Llamas <cmllamas@google.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "=?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?=" <arve@android.com>,
        Todd Kjos <tkjos@android.com>,
        Martijn Coenen <maco@android.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        Christian Brauner <brauner@kernel.org>,
        Carlos Llamas <cmllamas@google.com>,
        Suren Baghdasaryan <surenb@google.com>
Cc:     linux-kernel@vger.kernel.org, kernel-team@android.com,
        Alice Ryhl <aliceryhl@google.com>
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Precedence: bulk

Binder attributes the buffer allocation to the current->tgid everytime.
There is no need to pass this as a parameter so drop it.

Also add a few touchups to follow the coding guidelines. No functional
changes are introduced in this patch.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
---
 drivers/android/binder.c                |  2 +-
 drivers/android/binder_alloc.c          | 18 ++++++++----------
 drivers/android/binder_alloc.h          |  7 ++-----
 drivers/android/binder_alloc_selftest.c |  2 +-
 4 files changed, 12 insertions(+), 17 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 437d1097b118..45674af6310f 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -3225,7 +3225,7 @@ static void binder_transaction(struct binder_proc *proc,
 
 	t->buffer = binder_alloc_new_buf(&target_proc->alloc, tr->data_size,
 		tr->offsets_size, extra_buffers_size,
-		!reply && (t->flags & TF_ONE_WAY), current->tgid);
+		!reply && (t->flags & TF_ONE_WAY));
 	if (IS_ERR(t->buffer)) {
 		char *s;
 
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index 40a2ca0c0dea..b5c3e56318e1 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -319,7 +319,7 @@ static inline struct vm_area_struct *binder_alloc_get_vma(
 	return smp_load_acquire(&alloc->vma);
 }
 
-static bool debug_low_async_space_locked(struct binder_alloc *alloc, int pid)
+static bool debug_low_async_space_locked(struct binder_alloc *alloc)
 {
 	/*
 	 * Find the amount and size of buffers allocated by the current caller;
@@ -328,10 +328,11 @@ static bool debug_low_async_space_locked(struct binder_alloc *alloc, int pid)
 	 * and at some point we'll catch them in the act. This is more efficient
 	 * than keeping a map per pid.
 	 */
-	struct rb_node *n;
 	struct binder_buffer *buffer;
 	size_t total_alloc_size = 0;
+	int pid = current->tgid;
 	size_t num_buffers = 0;
+	struct rb_node *n;
 
 	for (n = rb_first(&alloc->allocated_buffers); n != NULL;
 		 n = rb_next(n)) {
@@ -364,8 +365,7 @@ static bool debug_low_async_space_locked(struct binder_alloc *alloc, int pid)
 static struct binder_buffer *binder_alloc_new_buf_locked(
 				struct binder_alloc *alloc,
 				size_t size,
-				int is_async,
-				int pid)
+				int is_async)
 {
 	struct rb_node *n = alloc->free_buffers.rb_node;
 	struct binder_buffer *buffer;
@@ -476,7 +476,6 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
 		     "%d: binder_alloc_buf size %zd got %pK\n",
 		      alloc->pid, size, buffer);
 	buffer->async_transaction = is_async;
-	buffer->pid = pid;
 	buffer->oneway_spam_suspect = false;
 	if (is_async) {
 		alloc->free_async_space -= size;
@@ -489,7 +488,7 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
 			 * of async space left (which is less than 10% of total
 			 * buffer size).
 			 */
-			buffer->oneway_spam_suspect = debug_low_async_space_locked(alloc, pid);
+			buffer->oneway_spam_suspect = debug_low_async_space_locked(alloc);
 		} else {
 			alloc->oneway_spam_detected = false;
 		}
@@ -532,7 +531,6 @@ static inline size_t sanitized_size(size_t data_size,
  * @offsets_size:       user specified buffer offset
  * @extra_buffers_size: size of extra space for meta-data (eg, security context)
  * @is_async:           buffer for async transaction
- * @pid:				pid to attribute allocation to (used for debugging)
  *
  * Allocate a new buffer given the requested sizes. Returns
  * the kernel version of the buffer pointer. The size allocated
@@ -545,8 +543,7 @@ struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc,
 					   size_t data_size,
 					   size_t offsets_size,
 					   size_t extra_buffers_size,
-					   int is_async,
-					   int pid)
+					   int is_async)
 {
 	struct binder_buffer *buffer;
 	size_t size;
@@ -569,7 +566,7 @@ struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc,
 	}
 
 	mutex_lock(&alloc->mutex);
-	buffer = binder_alloc_new_buf_locked(alloc, size, is_async, pid);
+	buffer = binder_alloc_new_buf_locked(alloc, size, is_async);
 	if (IS_ERR(buffer)) {
 		mutex_unlock(&alloc->mutex);
 		goto out;
@@ -578,6 +575,7 @@ struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc,
 	buffer->data_size = data_size;
 	buffer->offsets_size = offsets_size;
 	buffer->extra_buffers_size = extra_buffers_size;
+	buffer->pid = current->tgid;
 	mutex_unlock(&alloc->mutex);
 
 out:
diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h
index cb19677a5c15..bbc16bc6d5ac 100644
--- a/drivers/android/binder_alloc.h
+++ b/drivers/android/binder_alloc.h
@@ -49,15 +49,13 @@ struct binder_buffer {
 	unsigned async_transaction:1;
 	unsigned oneway_spam_suspect:1;
 	unsigned debug_id:27;
-
 	struct binder_transaction *transaction;
-
 	struct binder_node *target_node;
 	size_t data_size;
 	size_t offsets_size;
 	size_t extra_buffers_size;
 	unsigned long user_data;
-	int    pid;
+	int pid;
 };
 
 /**
@@ -125,8 +123,7 @@ struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc,
 					   size_t data_size,
 					   size_t offsets_size,
 					   size_t extra_buffers_size,
-					   int is_async,
-					   int pid);
+					   int is_async);
 void binder_alloc_init(struct binder_alloc *alloc);
 int binder_alloc_shrinker_init(void);
 void binder_alloc_shrinker_exit(void);
diff --git a/drivers/android/binder_alloc_selftest.c b/drivers/android/binder_alloc_selftest.c
index 341c73b4a807..ed753747e54c 100644
--- a/drivers/android/binder_alloc_selftest.c
+++ b/drivers/android/binder_alloc_selftest.c
@@ -119,7 +119,7 @@ static void binder_selftest_alloc_buf(struct binder_alloc *alloc,
 	int i;
 
 	for (i = 0; i < BUFFER_NUM; i++) {
-		buffers[i] = binder_alloc_new_buf(alloc, sizes[i], 0, 0, 0, 0);
+		buffers[i] = binder_alloc_new_buf(alloc, sizes[i], 0, 0, 0);
 		if (IS_ERR(buffers[i]) ||
 		    !check_buffer_pages_allocated(alloc, buffers[i],
 						  sizes[i])) {
-- 
2.43.0.rc2.451.g8631bc7472-goog