diff options
Diffstat (limited to 'drivers/android')
| -rw-r--r-- | drivers/android/binder.c | 2 | ||||
| -rw-r--r-- | drivers/android/binder_alloc.c | 55 | ||||
| -rw-r--r-- | drivers/android/binder_alloc.h | 5 | ||||
| -rw-r--r-- | drivers/android/binder_alloc_selftest.c | 2 |
4 files changed, 58 insertions, 6 deletions
diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 5b0376344dbe..37a505c41dec 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -3134,7 +3134,7 @@ 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)); + !reply && (t->flags & TF_ONE_WAY), current->tgid); if (IS_ERR(t->buffer)) { /* * -ESRCH indicates VMA cleared. The target is dying. diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index 8c98d12b7beb..910c53ba2c91 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -338,12 +338,50 @@ static inline struct vm_area_struct *binder_alloc_get_vma( return vma; } +static void debug_low_async_space_locked(struct binder_alloc *alloc, int pid) +{ + /* + * Find the amount and size of buffers allocated by the current caller; + * The idea is that once we cross the threshold, whoever is responsible + * for the low async space is likely to try to send another async txn, + * 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 = alloc->free_buffers.rb_node; + struct binder_buffer *buffer; + size_t total_alloc_size = 0; + size_t num_buffers = 0; + + for (n = rb_first(&alloc->allocated_buffers); n != NULL; + n = rb_next(n)) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + if (buffer->pid != pid) + continue; + if (!buffer->async_transaction) + continue; + total_alloc_size += binder_alloc_buffer_size(alloc, buffer) + + sizeof(struct binder_buffer); + num_buffers++; + } + + /* + * Warn if this pid has more than 50 transactions, or more than 50% of + * async space (which is 25% of total buffer size). + */ + if (num_buffers > 50 || total_alloc_size > alloc->buffer_size / 4) { + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%d: pid %d spamming oneway? %zd buffers allocated for a total size of %zd\n", + alloc->pid, pid, num_buffers, total_alloc_size); + } +} + static struct binder_buffer *binder_alloc_new_buf_locked( struct binder_alloc *alloc, size_t data_size, size_t offsets_size, size_t extra_buffers_size, - int is_async) + int is_async, + int pid) { struct rb_node *n = alloc->free_buffers.rb_node; struct binder_buffer *buffer; @@ -486,11 +524,20 @@ static struct binder_buffer *binder_alloc_new_buf_locked( buffer->offsets_size = offsets_size; buffer->async_transaction = is_async; buffer->extra_buffers_size = extra_buffers_size; + buffer->pid = pid; if (is_async) { alloc->free_async_space -= size + sizeof(struct binder_buffer); 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). + */ + debug_low_async_space_locked(alloc, pid); + } } return buffer; @@ -508,6 +555,7 @@ err_alloc_buf_struct_failed: * @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 @@ -520,13 +568,14 @@ 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 is_async, + int pid) { struct binder_buffer *buffer; mutex_lock(&alloc->mutex); buffer = binder_alloc_new_buf_locked(alloc, data_size, offsets_size, - extra_buffers_size, is_async); + extra_buffers_size, is_async, pid); mutex_unlock(&alloc->mutex); return buffer; } diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h index db9c1b984695..55d8b4106766 100644 --- a/drivers/android/binder_alloc.h +++ b/drivers/android/binder_alloc.h @@ -32,6 +32,7 @@ struct binder_transaction; * @offsets_size: size of array of offsets * @extra_buffers_size: size of space for other objects (like sg lists) * @user_data: user pointer to base of buffer space + * @pid: pid to attribute the buffer to (caller) * * Bookkeeping structure for binder transaction buffers */ @@ -51,6 +52,7 @@ struct binder_buffer { size_t offsets_size; size_t extra_buffers_size; void __user *user_data; + int pid; }; /** @@ -117,7 +119,8 @@ extern 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 is_async, + int pid); extern void binder_alloc_init(struct binder_alloc *alloc); extern int binder_alloc_shrinker_init(void); extern void binder_alloc_vma_close(struct binder_alloc *alloc); diff --git a/drivers/android/binder_alloc_selftest.c b/drivers/android/binder_alloc_selftest.c index 4151d9938255..c2b323bc3b3a 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); + buffers[i] = binder_alloc_new_buf(alloc, sizes[i], 0, 0, 0, 0); if (IS_ERR(buffers[i]) || !check_buffer_pages_allocated(alloc, buffers[i], sizes[i])) { |