binder: use freezable blocking calls

Avoid waking up every thread sleeping in a binder call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c
index 1567ac296b393163225237c830c48a726e529b4e..1ffc2ebdf612df7afbf90371e7ba4a4b226131b3 100644 (file)
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -20,6 +20,7 @@
 #include <asm/cacheflush.h>
 #include <linux/fdtable.h>
 #include <linux/file.h>
+#include <linux/freezer.h>
 #include <linux/fs.h>
 #include <linux/list.h>
 #include <linux/miscdevice.h>
@@ -2140,13 +2141,13 @@ retry:
                        if (!binder_has_proc_work(proc, thread))
                                ret = -EAGAIN;
                } else
-                       ret = wait_event_interruptible_exclusive(proc->wait, binder_has_proc_work(proc, thread));
+                       ret = wait_event_freezable_exclusive(proc->wait, binder_has_proc_work(proc, thread));
        } else {
                if (non_block) {
                        if (!binder_has_thread_work(thread))
                                ret = -EAGAIN;
                } else
-                       ret = wait_event_interruptible(thread->wait, binder_has_thread_work(thread));
+                       ret = wait_event_freezable(thread->wait, binder_has_thread_work(thread));
        }
 
        binder_lock(__func__);