diff options
Diffstat (limited to 'drivers/xen/events.c')
| -rw-r--r-- | drivers/xen/events.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/drivers/xen/events.c b/drivers/xen/events.c index c8b9d9fc77b..0b14a9bbbb0 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -1388,14 +1388,21 @@ static void __xen_evtchn_do_upcall(void) pending_bits = active_evtchns(cpu, s, word_idx); bit_idx = 0; /* usually scan entire word from start */ + /* + * We scan the starting word in two parts. + * + * 1st time: start in the middle, scanning the + * upper bits. + * + * 2nd time: scan the whole word (not just the + * parts skipped in the first pass) -- if an + * event in the previously scanned bits is + * pending again it would just be scanned on + * the next loop anyway. + */ if (word_idx == start_word_idx) { - /* We scan the starting word in two parts */ if (i == 0) - /* 1st time: start in the middle */ bit_idx = start_bit_idx; - else - /* 2nd time: mask bits done already */ - bit_idx &= (1UL << start_bit_idx) - 1; } do { |