[PATCH -rt] Make RCU API inaccessible to non-GPL Linux kernel modules
From: Paul E. McKenney
Date: Tue May 02 2006 - 14:23:55 EST
Hello!
This patch removes synchronize_kernel() (deprecated 2-APR-2005 in
http://lkml.org/lkml/2005/4/3/11) and makes the RCU API inaccessible
to non-GPL Linux kernel modules (as was announced more than one year
ago in http://lkml.org/lkml/2005/4/3/8). Tested on x86 and ppc64.
Same as the one sent yesterday, but for -rt rather than mainline.
Ingo, please apply.
Thanx, Paul
Signed-off-by: <paulmck@xxxxxxxxxx>
---
Documentation/RCU/whatisRCU.txt | 1 -
Documentation/feature-removal-schedule.txt | 14 --------------
include/linux/rcupdate.h | 3 +--
kernel/rcupdate.c | 13 ++-----------
kernel/rcupreempt.c | 15 +++------------
5 files changed, 6 insertions(+), 40 deletions(-)
diff -urpNa -X dontdiff linux-2.6.16-rt18/Documentation/RCU/whatisRCU.txt linux-2.6.16-rt18-GPLRCU/Documentation/RCU/whatisRCU.txt
--- linux-2.6.16-rt18/Documentation/RCU/whatisRCU.txt 2006-03-19 21:53:29.000000000 -0800
+++ linux-2.6.16-rt18-GPLRCU/Documentation/RCU/whatisRCU.txt 2006-05-02 08:42:23.000000000 -0700
@@ -790,7 +790,6 @@ RCU pointer update:
RCU grace period:
- synchronize_kernel (deprecated)
synchronize_net
synchronize_sched
synchronize_rcu
diff -urpNa -X dontdiff linux-2.6.16-rt18/Documentation/feature-removal-schedule.txt linux-2.6.16-rt18-GPLRCU/Documentation/feature-removal-schedule.txt
--- linux-2.6.16-rt18/Documentation/feature-removal-schedule.txt 2006-03-19 21:53:29.000000000 -0800
+++ linux-2.6.16-rt18-GPLRCU/Documentation/feature-removal-schedule.txt 2006-05-02 08:43:24.000000000 -0700
@@ -32,21 +32,6 @@ Who: Adrian Bunk <bunk@xxxxxxxxx>
---------------------------
-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@xxxxxxxxxx>
-
----------------------------
-
What: raw1394: requests of type RAW1394_REQ_ISO_SEND, RAW1394_REQ_ISO_LISTEN
When: November 2005
Why: Deprecated in favour of the new ioctl-based rawiso interface, which is
diff -urpNa -X dontdiff linux-2.6.16-rt18/include/linux/rcupdate.h linux-2.6.16-rt18-GPLRCU/include/linux/rcupdate.h
--- linux-2.6.16-rt18/include/linux/rcupdate.h 2006-05-02 08:25:48.000000000 -0700
+++ linux-2.6.16-rt18-GPLRCU/include/linux/rcupdate.h 2006-05-02 08:29:55.000000000 -0700
@@ -268,7 +268,7 @@ extern int rcu_pending(int cpu);
* softirq handlers will have completed, since in some kernels, these
* handlers can run in process context, and can block.
*
- * This primitive provides the guarantees made by the (deprecated)
+ * This primitive provides the guarantees made by the (now removed)
* synchronize_kernel() API. In contrast, synchronize_rcu() only
* guarantees that rcu_read_lock() sections will have completed.
* In "classic RCU", these two guarantees happen to be one and
@@ -292,7 +292,6 @@ extern void FASTCALL(call_rcu(struct rcu
void (*func)(struct rcu_head *head)));
extern void FASTCALL(call_rcu_bh(struct rcu_head *head,
void (*func)(struct rcu_head *head)));
-extern __deprecated_for_modules void synchronize_kernel(void);
extern void synchronize_rcu(void);
void synchronize_idle(void);
diff -urpNa -X dontdiff linux-2.6.16-rt18/kernel/rcupdate.c linux-2.6.16-rt18-GPLRCU/kernel/rcupdate.c
--- linux-2.6.16-rt18/kernel/rcupdate.c 2006-05-02 08:25:48.000000000 -0700
+++ linux-2.6.16-rt18-GPLRCU/kernel/rcupdate.c 2006-05-02 08:34:28.000000000 -0700
@@ -560,21 +560,12 @@ void __init rcu_init(void)
register_cpu_notifier(&rcu_nb);
}
-/*
- * Deprecated, use synchronize_rcu() or synchronize_sched() instead.
- */
-void synchronize_kernel(void)
-{
- synchronize_rcu();
-}
-
module_param(blimit, int, 0);
module_param(qhimark, int, 0);
module_param(qlowmark, int, 0);
#ifdef CONFIG_SMP
module_param(rsinterval, int, 0);
#endif
-EXPORT_SYMBOL(call_rcu); /* WARNING: GPL-only in April 2006. */
-EXPORT_SYMBOL(call_rcu_bh); /* WARNING: GPL-only in April 2006. */
+EXPORT_SYMBOL_GPL(call_rcu);
+EXPORT_SYMBOL_GPL(call_rcu_bh);
EXPORT_SYMBOL_GPL(synchronize_rcu);
-EXPORT_SYMBOL(synchronize_kernel); /* WARNING: GPL-only in April 2006. */
diff -urpNa -X dontdiff linux-2.6.16-rt18/kernel/rcupreempt.c linux-2.6.16-rt18-GPLRCU/kernel/rcupreempt.c
--- linux-2.6.16-rt18/kernel/rcupreempt.c 2006-05-02 08:25:48.000000000 -0700
+++ linux-2.6.16-rt18-GPLRCU/kernel/rcupreempt.c 2006-05-02 08:37:55.000000000 -0700
@@ -388,14 +388,6 @@ void __init rcu_init(void)
tasklet_init(&rcu_data.rcu_tasklet, rcu_process_callbacks, 0UL);
}
-/*
- * Deprecated, use synchronize_rcu() or synchronize_sched() instead.
- */
-void synchronize_kernel(void)
-{
- synchronize_rcu();
-}
-
#ifdef CONFIG_RCU_STATS
int rcu_read_proc_data(char *page)
{
@@ -463,10 +455,9 @@ int rcu_read_proc_ctrs_data(char *page)
#endif /* #ifdef CONFIG_RCU_STATS */
-EXPORT_SYMBOL(call_rcu); /* WARNING: GPL-only in April 2006. */
+EXPORT_SYMBOL_GPL(call_rcu);
EXPORT_SYMBOL_GPL(rcu_batches_completed);
EXPORT_SYMBOL_GPL(synchronize_rcu);
EXPORT_SYMBOL_GPL(synchronize_sched);
-EXPORT_SYMBOL(rcu_read_lock); /* WARNING: GPL-only in April 2006. */
-EXPORT_SYMBOL(rcu_read_unlock); /* WARNING: GPL-only in April 2006. */
-EXPORT_SYMBOL(synchronize_kernel); /* WARNING: Removal in April 2006. */
+EXPORT_SYMBOL_GPL(rcu_read_lock);
+EXPORT_SYMBOL_GPL(rcu_read_unlock);
-
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