mirror of
https://github.com/torvalds/linux
synced 2024-09-21 03:28:37 +00:00
db496944fd
similar to x64 add support for bpf-to-bpf calls. When program has calls to in-kernel helpers the target call offset is known at JIT time and arm64 architecture needs 2 passes. With bpf-to-bpf calls the dynamically allocated function start is unknown until all functions of the program are JITed. Therefore (just like x64) arm64 JIT needs one extra pass over the program to emit correct call offsets. Implementation detail: Avoid being too clever in 64-bit immediate moves and always use 4 instructions (instead of 3-4 depending on the address) to make sure only one extra pass is needed. If some future optimization would make it worth while to optimize 'call 64-bit imm' further, the JIT would need to do 4 passes over the program instead of 3 as in this patch. For typical bpf program address the mov needs 3 or 4 insns, so unconditional 4 insns to save extra pass is a worthy trade off at this state of JIT. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> |
||
|---|---|---|
| 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.