From e6a92013ba458804161c0c5b6d134d82204dc233 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Wed, 4 Oct 2006 02:17:05 -0700 Subject: [PATCH] SRCU: report out-of-memory errors Currently the init_srcu_struct() routine has no way to report out-of-memory errors. This patch (as761) makes it return -ENOMEM when the per-cpu data allocation fails. The patch also makes srcu_init_notifier_head() report a BUG if a notifier head can't be initialized. Perhaps it should return -ENOMEM instead, but in the most likely cases where this might occur I don't think any recovery is possible. Notifier chains generally are not created dynamically. [akpm@osdl.org: avoid statement-with-side-effect in macro] Signed-off-by: Alan Stern Acked-by: Paul E. McKenney Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/srcu.c | 5 +++-- kernel/sys.c | 3 ++- 2 files changed, 5 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/srcu.c b/kernel/srcu.c index 7e1979f624ba..3507cabe963b 100644 --- a/kernel/srcu.c +++ b/kernel/srcu.c @@ -42,11 +42,12 @@ * to any other function. Each srcu_struct represents a separate domain * of SRCU protection. */ -void init_srcu_struct(struct srcu_struct *sp) +int init_srcu_struct(struct srcu_struct *sp) { sp->completed = 0; - sp->per_cpu_ref = alloc_percpu(struct srcu_struct_array); mutex_init(&sp->mutex); + sp->per_cpu_ref = alloc_percpu(struct srcu_struct_array); + return (sp->per_cpu_ref ? 0 : -ENOMEM); } /* diff --git a/kernel/sys.c b/kernel/sys.c index fd5c71006775..98489d82801b 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -517,7 +517,8 @@ EXPORT_SYMBOL_GPL(srcu_notifier_call_chain); void srcu_init_notifier_head(struct srcu_notifier_head *nh) { mutex_init(&nh->mutex); - init_srcu_struct(&nh->srcu); + if (init_srcu_struct(&nh->srcu) < 0) + BUG(); nh->head = NULL; } -- cgit v1.2.3