On 5/12/22 9:45 AM, Hari Bathini wrote:
This patchset adds atomic operations to the eBPF instruction set on
powerpc. The instructions that are added here can be summarised with
this list of kernel operations for ppc64:
* atomic[64]_[fetch_]add
* atomic[64]_[fetch_]and
* atomic[64]_[fetch_]or
* atomic[64]_[fetch_]xor
* atomic[64]_xchg
* atomic[64]_cmpxchg
and this list of kernel operations for ppc32:
* atomic_[fetch_]add
* atomic_[fetch_]and
* atomic_[fetch_]or
* atomic_[fetch_]xor
* atomic_xchg
* atomic_cmpxchg
The following are left out of scope for this effort:
* 64 bit operations on ppc32.
* Explicit memory barriers, 16 and 8 bit operations on both ppc32
& ppc64.
The first patch adds support for bitwsie atomic operations on ppc64.
The next patch adds fetch variant support for these instructions. The
third patch adds support for xchg and cmpxchg atomic operations on
ppc64. Patch #4 adds support for 32-bit atomic bitwise operations on
ppc32. patch #5 adds support for xchg and cmpxchg atomic operations
on ppc32.
Thanks for adding these, Hari! I presume they'll get routed via Michael,
right? One thing that may be worth adding to the commit log as well is
the test result from test_bpf.ko given it has an extensive suite around
atomics useful for testing corner cases in JITs.
Hari Bathini (5):
bpf ppc64: add support for BPF_ATOMIC bitwise operations
bpf ppc64: add support for atomic fetch operations
bpf ppc64: Add instructions for atomic_[cmp]xchg
bpf ppc32: add support for BPF_ATOMIC bitwise operations
bpf ppc32: Add instructions for atomic_[cmp]xchg
arch/powerpc/net/bpf_jit_comp32.c | 62 +++++++++++++++++-----
arch/powerpc/net/bpf_jit_comp64.c | 87 +++++++++++++++++++++----------
2 files changed, 108 insertions(+), 41 deletions(-)
