commit 2f6d7bb93c157b874efb79a2d1583a4c368bf89a
author Sirshak Das <sirshak.das@arm.com> Wed Oct 03 22:53:51 2018 +0000
committer Damjan Marion <dmarion@me.com> Fri Oct 19 07:10:47 2018 +0000
tree 05dc2867c598cbb8d711f074b4b0eb62dd464f41
parent bf3443b0f852f5a4c551d12f926defbd047f2161

vppinfra: add atomic macros for __sync builtins

This is first part of addition of atomic macros with only macros for
__sync builtins.

- Based on earlier patch by Damjan (https://gerrit.fd.io/r/#/c/10729/)
Additionally
- clib_atomic_release macro added and used in the absence
of any memory barrier.
- clib_atomic_bool_cmp_and_swap added

Change-Id: Ie4e48c1e184a652018d1d0d87c4be80ddd180a3b
Original-patch-by: Damjan Marion <damarion@cisco.com>
Signed-off-by: Sirshak Das <sirshak.das@arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Reviewed-by: Ola Liljedahl <ola.liljedahl@arm.com>
Reviewed-by: Steve Capper <steve.capper@arm.com>

src/vnet/mfib/mfib_signal.c

diff --git a/src/vnet/mfib/mfib_signal.c b/src/vnet/mfib/mfib_signal.c
index ce9a664..176e8ec 100644
--- a/src/vnet/mfib/mfib_signal.c
+++ b/src/vnet/mfib/mfib_signal.c
@@ -71,14 +71,14 @@
 static inline void
 mfib_signal_lock_aquire (void)
 {
-    while (__sync_lock_test_and_set (&mfib_signal_pending.mip_lock, 1))
+    while (clib_atomic_test_and_set (&mfib_signal_pending.mip_lock))
         ;
 }
 
 static inline void
 mfib_signal_lock_release (void)
 {
-    mfib_signal_pending.mip_lock = 0;
+  clib_atomic_release(&mfib_signal_pending.mip_lock);
 }
 
 #define MFIB_SIGNAL_CRITICAL_SECTION(_body) \
@@ -117,8 +117,8 @@
         mfs = pool_elt_at_index(mfib_signal_pool, si);
         mfi = mfib_itf_get(mfs->mfs_itf);
         mfi->mfi_si = INDEX_INVALID;
-        __sync_fetch_and_and(&mfi->mfi_flags,
-                             ~MFIB_ITF_FLAG_SIGNAL_PRESENT);
+        clib_atomic_fetch_and(&mfi->mfi_flags,
+			      ~MFIB_ITF_FLAG_SIGNAL_PRESENT);
 
 
         vl_mfib_signal_send_one(reg, context, mfs);