mainlining shenanigans
This patch add the optimization frontend, but adding a new eBPF IR scan pass "nfp_bpf_opt_ldst_gather". The pass will traverse the IR to recognize the load/store pairs sequences that come from lowering of memory copy builtins. The gathered memory copy information will be kept in the meta info structure of the first load instruction in the sequence and will be consumed by the optimization backend added in the previous patches. NOTE: a sequence with cross memory access doesn't qualify this optimization, i.e. if one load in the sequence will load from place that has been written by previous store. This is because when we turn the sequence into single CPP operation, we are reading all contents at once into NFP transfer registers, then write them out as a whole. This is not identical with what the original load/store sequence is doing. Detecting cross memory access for two random pointers will be difficult, fortunately under XDP/eBPF's restrictied runtime environment, the copy normally happen among map, packet data and stack, they do not overlap with each other. And for cases supported by NFP, cross memory access will only happen on PTR_TO_PACKET. Fortunately for this, there is ID information that we could do accurate memory alias check. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.