From 7f7b603393498505e8612bd32ceabddbc133d4af Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Fri, 26 Nov 2010 14:19:09 +0000 Subject: [PATCH] xenpaging: print info when free request slots drop below 2 Add debugging aid to free request slots in the ring buffer. It should not happen that the ring gets full, print info anyway if it happens. Signed-off-by: Olaf Hering --- xen/arch/x86/mm/mem_event.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/xen/arch/x86/mm/mem_event.c b/xen/arch/x86/mm/mem_event.c index 5187a72a6c..83b76d5f9f 100644 --- a/xen/arch/x86/mm/mem_event.c +++ b/xen/arch/x86/mm/mem_event.c @@ -152,6 +152,11 @@ int mem_event_check_ring(struct domain *d) mem_event_ring_lock(d); free_requests = RING_FREE_REQUESTS(&d->mem_event.front_ring); + if ( unlikely(free_requests < 2) ) + { + gdprintk(XENLOG_INFO, "free request slots: %d\n", free_requests); + WARN_ON(free_requests == 0); + } ring_full = free_requests < MEM_EVENT_RING_THRESHOLD; if ( (curr->domain->domain_id == d->domain_id) && ring_full ) -- 2.30.2