From 83fe27ea531161a655f02dc7732d14cfaa27fd5d Mon Sep 17 00:00:00 2001 From: Pranith Kumar Date: Fri, 5 Dec 2014 11:24:45 -0500 Subject: rcu: Make SRCU optional by using CONFIG_SRCU SRCU is not necessary to be compiled by default in all cases. For tinification efforts not compiling SRCU unless necessary is desirable. The current patch tries to make compiling SRCU optional by introducing a new Kconfig option CONFIG_SRCU which is selected when any of the components making use of SRCU are selected. If we do not select CONFIG_SRCU, srcu.o will not be compiled at all. text data bss dec hex filename 2007 0 0 2007 7d7 kernel/rcu/srcu.o Size of arch/powerpc/boot/zImage changes from text data bss dec hex filename 831552 64180 23944 919676 e087c arch/powerpc/boot/zImage : before 829504 64180 23952 917636 e0084 arch/powerpc/boot/zImage : after so the savings are about ~2000 bytes. Signed-off-by: Pranith Kumar CC: Paul E. McKenney CC: Josh Triplett CC: Lai Jiangshan Signed-off-by: Paul E. McKenney [ paulmck: resolve conflict due to removal of arch/ia64/kvm/Kconfig. ] --- kernel/notifier.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel/notifier.c') diff --git a/kernel/notifier.c b/kernel/notifier.c index 4803da6eab62..ae9fc7cc360e 100644 --- a/kernel/notifier.c +++ b/kernel/notifier.c @@ -402,6 +402,7 @@ int raw_notifier_call_chain(struct raw_notifier_head *nh, } EXPORT_SYMBOL_GPL(raw_notifier_call_chain); +#ifdef CONFIG_SRCU /* * SRCU notifier chain routines. Registration and unregistration * use a mutex, and call_chain is synchronized by SRCU (no locks). @@ -528,6 +529,8 @@ void srcu_init_notifier_head(struct srcu_notifier_head *nh) } EXPORT_SYMBOL_GPL(srcu_init_notifier_head); +#endif /* CONFIG_SRCU */ + static ATOMIC_NOTIFIER_HEAD(die_chain); int notrace notify_die(enum die_val val, const char *str, -- cgit v1.2.3-55-g7522