Le jeudi 21 juillet 2011 à 11:51 +1000, Matt Evans a écrit : > An implementation of a code generator for BPF programs to speed up packet > filtering on PPC64, inspired by Eric Dumazet's x86-64 version. > > Filter code is generated as an ABI-compliant function in module_alloc()'d mem > with stackframe & prologue/epilogue generated if required (simple filters > don't > need anything more than an li/blr). The filter's local variables, M[], live > in > registers. Supports all BPF opcodes, although "complicated" loads from > negative > packet offsets (e.g. SKF_LL_OFF) are not yet supported. > > There are a couple of further optimisations left for future work; many-pass > assembly with branch-reach reduction and a register allocator to push M[] > variables into volatile registers would improve the code quality further. > > This currently supports big-endian 64-bit PowerPC only (but is fairly simple > to port to PPC32 or LE!). > > Enabled in the same way as x86-64: > > echo 1 > /proc/sys/net/core/bpf_jit_enable > > Or, enabled with extra debug output: > > echo 2 > /proc/sys/net/core/bpf_jit_enable > > Signed-off-by: Matt Evans <m...@ozlabs.org> > --- > > V3: Added BUILD_BUG_ON to assert PACA CPU ID is 16bits, made a comment (in > LD_MSH) a bit clearer, ratelimited "Unknown opcode" error and moved > bpf_jit.S to bpf_jit_64.S (it doesn't make sense to rename bpf_jit_comp.c > as > small portions will eventually get split out into _32/_64.c files when we > do > 32bit support). > > arch/powerpc/Kconfig | 1 + > arch/powerpc/Makefile | 3 +- > arch/powerpc/include/asm/ppc-opcode.h | 40 ++ > arch/powerpc/net/Makefile | 4 + > arch/powerpc/net/bpf_jit.h | 227 +++++++++++ > arch/powerpc/net/bpf_jit_64.S | 138 +++++++ > arch/powerpc/net/bpf_jit_comp.c | 694 > +++++++++++++++++++++++++++++++++ > 7 files changed, 1106 insertions(+), 1 deletions(-)
Nice work Matt ;) Acked-by: Eric Dumazet <eric.duma...@gmail.com> Thanks _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
