Freezer: make kernel threads nonfreezable by default

[mirror_ubuntu-artful-kernel.git] / Documentation / power / swsusp.txt

diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt
index 152b510d1bbb5560945e3550c9b0276f7aa452ab..aea7e920966753193c6139d84e7839f7de485ebe 100644 (file)
--- a/Documentation/power/swsusp.txt
+++ b/Documentation/power/swsusp.txt
@@ -140,21 +140,11 @@ should be sent to the mailing list available through the suspend2
 website, and not to the Linux Kernel Mailing List. We are working
 toward merging suspend2 into the mainline kernel.
 
-Q: A kernel thread must voluntarily freeze itself (call 'refrigerator').
-I found some kernel threads that don't do it, and they don't freeze
-so the system can't sleep. Is this a known behavior?
-
-A: All such kernel threads need to be fixed, one by one. Select the
-place where the thread is safe to be frozen (no kernel semaphores
-should be held at that point and it must be safe to sleep there), and
-add:
-
-       try_to_freeze();
-
-If the thread is needed for writing the image to storage, you should
-instead set the PF_NOFREEZE process flag when creating the thread (and
-be very careful).
+Q: What is the freezing of tasks and why are we using it?
 
+A: The freezing of tasks is a mechanism by which user space processes and some
+kernel threads are controlled during hibernation or system-wide suspend (on some
+architectures).  See freezing-of-tasks.txt for details.
 
 Q: What is the difference between "platform" and "shutdown"?