On Wed, Mar 12, 2014 at 12:22 PM, David Miller <da...@davemloft.net> wrote: > From: Alexei Starovoitov <a...@plumgrid.com> > Date: Mon, 10 Mar 2014 21:41:30 -0700 > >> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h >> index 1a869488b8ae..2c13d000389c 100644 >> --- a/include/linux/netdevice.h >> +++ b/include/linux/netdevice.h >> @@ -3054,6 +3054,7 @@ extern int netdev_max_backlog; >> extern int netdev_tstamp_prequeue; >> extern int weight_p; >> extern int bpf_jit_enable; >> +extern int bpf_ext_enable; > > I don't like seeing config ifdefs in C code, so please adjust the > bpf_jit_enable declaration with something like: > > #ifdef CONFIG_BPF_JIT > extern int bpf_jit_enable; > #else > #define bpf_jit_enable 0 > #endif
agree. that's definitely cleaner. >> +#ifdef CONFIG_64BIT >> + DL(BPF_STX, BPF_XADD, BPF_DW) >> +#endif > ... >> +#ifdef CONFIG_64BIT >> +BPF_STX_BPF_XADD_BPF_DW: /* lock xadd *(u64 *)(A + insn->off) += X */ >> + atomic64_add((u64)X, (atomic64_t *)(ulong)(A + insn->off)); >> + CONT; >> +#endif > > I'm not too happy about instructions which are only available on > certain architectures. > > I'd rather see best effort emulation than wholesale lack of support. > > We have an implementation of 64-bit atomics for 32-bit systems or > those without true atomic compare-and-saw etc. ops in lib/atomic64.c > so the routines are always available. Good point. Will do. Thanks -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
