From: Brian Brooks Date: Wed, 25 Jul 2018 21:08:19 +0000 (-0500) Subject: samples/bpf: xdpsock: order memory on AArch64 X-Git-Tag: v4.19-rc1~140^2~108^2~17 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=598135e7444c121f11c8c16495ba1e6ab122678f;p=linux.git samples/bpf: xdpsock: order memory on AArch64 Define u_smp_rmb() and u_smp_wmb() to respective barrier instructions. This ensures the processor will order accesses to queue indices against accesses to queue ring entries. Signed-off-by: Brian Brooks Acked-by: Björn Töpel Signed-off-by: Daniel Borkmann --- diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c index 5904b1543831..1e82f7c617c3 100644 --- a/samples/bpf/xdpsock_user.c +++ b/samples/bpf/xdpsock_user.c @@ -145,8 +145,13 @@ static void dump_stats(void); } while (0) #define barrier() __asm__ __volatile__("": : :"memory") +#ifdef __aarch64__ +#define u_smp_rmb() __asm__ __volatile__("dmb ishld": : :"memory") +#define u_smp_wmb() __asm__ __volatile__("dmb ishst": : :"memory") +#else #define u_smp_rmb() barrier() #define u_smp_wmb() barrier() +#endif #define likely(x) __builtin_expect(!!(x), 1) #define unlikely(x) __builtin_expect(!!(x), 0)