Dave Thaler wrote: > From: Dave Thaler <dthaler@xxxxxxxxxxxxx> > > Improve clarity by adding an example of a signed comparison instruction > > Signed-off-by: Dave Thaler <dthaler@xxxxxxxxxxxxx> > --- > Documentation/bpf/instruction-set.rst | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/Documentation/bpf/instruction-set.rst b/Documentation/bpf/instruction-set.rst > index 5e43e14abe8..b4464058905 100644 > --- a/Documentation/bpf/instruction-set.rst > +++ b/Documentation/bpf/instruction-set.rst > @@ -11,7 +11,8 @@ Documentation conventions > ========================= > > For brevity, this document uses the type notion "u64", "u32", etc. > -to mean an unsigned integer whose width is the specified number of bits. > +to mean an unsigned integer whose width is the specified number of bits, > +and "s32", etc. to mean a signed integer of the specified number of bits. > > Registers and calling convention > ================================ > @@ -264,6 +265,14 @@ BPF_JSLE 0xd0 PC += off if dst <= src signed > The eBPF program needs to store the return value into register R0 before doing a > BPF_EXIT. > > +Example: > + > +``BPF_JSGE | BPF_X | BPF_JMP32`` (0x7e) means:: > + > + if (s32)dst s>= (s32)src goto +offset > + > +where 's>=' indicates a signed '>=' comparison. > + > Helper functions > ~~~~~~~~~~~~~~~~ > Acked-by: John Fastabend <john.fastabend@xxxxxxxxx>
