[PATCH] kernel/rcupdate.c: make the exports EXPORT_SYMBOL_GPL
The gpl exports need to be put back. Moving them to GPL -- but in a
measured manner, as I proposed on this list some months ago -- is fine.
Changing these particular exports precipitously is most definitely -not-
fine. Here is my earlier proposal:
http://marc.theaimsgroup.com/?l=linux-kernel&m=110520930301813&w=2
See below for a patch that puts the exports back, along with an updated
version of my earlier patch that starts the process of moving them to GPL.
I will also be following this message with RFC patches that introduce two
(EXPORT_SYMBOL_GPL) interfaces to replace synchronize_kernel(), which then
becomes deprecated.
Signed-off-by: <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 56627c1..d3c52dd 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -48,3 +48,18 @@
Why: Replaced by ->compat_ioctl in file_operations and other method
vecors.
Who: Andi Kleen <ak@muc.de>, Christoph Hellwig <hch@lst.de>
+
+---------------------------
+
+What: RCU API moves to EXPORT_SYMBOL_GPL
+When: April 2006
+Files: include/linux/rcupdate.h, kernel/rcupdate.c
+Why: Outside of Linux, the only implementations of anything even
+ vaguely resembling RCU that I am aware of are in DYNIX/ptx,
+ VM/XA, Tornado, and K42. I do not expect anyone to port binary
+ drivers or kernel modules from any of these, since the first two
+ are owned by IBM and the last two are open-source research OSes.
+ So these will move to GPL after a grace period to allow
+ people, who might be using implementations that I am not aware
+ of, to adjust to this upcoming change.
+Who: Paul E. McKenney <paulmck@us.ibm.com>
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index d00eded..ad49772 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -465,6 +465,6 @@
}
module_param(maxbatch, int, 0);
-EXPORT_SYMBOL_GPL(call_rcu);
-EXPORT_SYMBOL_GPL(call_rcu_bh);
-EXPORT_SYMBOL_GPL(synchronize_kernel);
+EXPORT_SYMBOL(call_rcu); /* WARNING: GPL-only in April 2006. */
+EXPORT_SYMBOL(call_rcu_bh); /* WARNING: GPL-only in April 2006. */
+EXPORT_SYMBOL(synchronize_kernel); /* WARNING: GPL-only in April 2006. */