From 157dca953e2510afa1d16b929472c0f682531355 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Thu, 12 Feb 2009 16:35:01 -0500 Subject: [PATCH] Add smp_mc() to force_mb_single_thread so we don't assume anything from the OS. Signed-off-by: Mathieu Desnoyers --- urcu.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/urcu.c b/urcu.c index 8381f7b..8cbdef9 100644 --- a/urcu.c +++ b/urcu.c @@ -92,7 +92,14 @@ static void force_mb_single_thread(pthread_t tid) { assert(reader_data); sig_done = 0; - smp_mb(); /* write sig_done before sending the signals */ + /* + * pthread_kill has a smp_mb(). But beware, we assume it performs + * a cache flush on architectures with non-coherent cache. Let's play + * safe and don't assume anything : we use smp_mc() to make sure the + * cache flush is enforced. + * smp_mb(); write sig_done before sending the signals + */ + smp_mc(); /* write sig_done before sending the signals */ pthread_kill(tid, SIGURCU); /* * Wait for sighandler (and thus mb()) to execute on every thread. @@ -115,9 +122,12 @@ static void force_mb_all_threads(void) sig_done = 0; /* * pthread_kill has a smp_mb(). But beware, we assume it performs - * a cache flush on architectures with non-coherent cache. + * a cache flush on architectures with non-coherent cache. Let's play + * safe and don't assume anything : we use smp_mc() to make sure the + * cache flush is enforced. * smp_mb(); write sig_done before sending the signals */ + smp_mc(); /* write sig_done before sending the signals */ for (index = reader_data; index < reader_data + num_readers; index++) pthread_kill(index->tid, SIGURCU); /* -- 2.34.1