The atomic functions smp_load_acquire() and smp_store_release()
were introduced in Linux 3.14. Older kernels miss the functions:
kni_fifo.h:19:2: error:
implicit declaration of function ‘smp_load_acquire’
kni_fifo.h:30:2: error:
implicit declaration of function ‘smp_store_release’
The fallback is to drop the atomic barrier, as it was before
the commit below.
Fixes: 711859cd0d07 ("kni: fix kernel FIFO synchronization")
Signed-off-by: Thomas Monjalon <tho...@monjalon.net>
---
kernel/linux/kni/kni_fifo.h | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/kernel/linux/kni/kni_fifo.h b/kernel/linux/kni/kni_fifo.h
index 2cb3a4a7b..3c0be311f 100644
--- a/kernel/linux/kni/kni_fifo.h
+++ b/kernel/linux/kni/kni_fifo.h
@@ -8,6 +8,13 @@
#include <exec-env/rte_kni_common.h>
+#ifndef smp_load_acquire
+#define smp_load_acquire(a) (*(a))
+#endif
+#ifndef smp_store_release
+#define smp_store_release(a, b) *(a) = (b)
+#endif
+
/**
* Adds num elements into the fifo. Return the number actually written
*/
--
2.19.0
