From: Eric Dumazet Date: Wed, 15 Dec 2010 19:45:28 +0000 (+0000) Subject: filter: optimize accesses to ancillary data X-Git-Tag: v2.6.38-rc1~476^2~111 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=12b16dadbc2406144d408754f96d0f44aa016239;p=pandora-kernel.git filter: optimize accesses to ancillary data We can translate pseudo load instructions at filter check time to dedicated instructions to speed up filtering and avoid one switch(). libpcap currently uses SKF_AD_PROTOCOL, but custom filters probably use other ancillary accesses. Note : I made the assertion that ancillary data was always accessed with BPF_LD|BPF_?|BPF_ABS instructions, not with BPF_LD|BPF_?|BPF_IND ones (offset given by K constant, not by K + X register) On x86_64, this saves a few bytes of text : # size net/core/filter.o.* text data bss dec hex filename 4864 0 0 4864 1300 net/core/filter.o.new 4944 0 0 4944 1350 net/core/filter.o.old Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- Reading git-diff-tree failed