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bpf, arm64: support more atomic ops#1876

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bpf, arm64: support more atomic ops#1876
tsipa wants to merge 5 commits intobpf-nextfrom
series/611843=>bpf-next

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@tsipa tsipa commented Feb 7, 2022

Pull request for series with
subject: bpf, arm64: support more atomic ops
version: 3
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843

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tsipa commented Feb 7, 2022

Master branch: 422ee58
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

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tsipa commented Feb 7, 2022

Master branch: e91d280
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from e5a7e77 to a2bf40b Compare February 7, 2022 16:16
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tsipa commented Feb 7, 2022

Master branch: 128dac5
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from a2bf40b to 54545d9 Compare February 7, 2022 20:23
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tsipa commented Feb 8, 2022

Master branch: 80123f0
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 54545d9 to 4c91f40 Compare February 8, 2022 02:24
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tsipa commented Feb 8, 2022

Master branch: 5d1e9f4
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 4c91f40 to 2115937 Compare February 8, 2022 02:35
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tsipa commented Feb 8, 2022

Master branch: f95f768
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 2115937 to 767ce3d Compare February 8, 2022 17:32
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tsipa commented Feb 8, 2022

Master branch: 5912fcb
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 767ce3d to 251e98b Compare February 8, 2022 20:33
@tsipa tsipa added the needs-ack label Feb 8, 2022
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tsipa commented Feb 8, 2022

Master branch: 4172843
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 251e98b to 7b70947 Compare February 8, 2022 21:42
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tsipa commented Feb 8, 2022

Master branch: 19face1
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 7b70947 to e817258 Compare February 8, 2022 22:57
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tsipa commented Feb 9, 2022

Master branch: cca6242
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from e817258 to 7be1b81 Compare February 9, 2022 02:41
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tsipa commented Feb 9, 2022

Master branch: 8dd039a
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 7be1b81 to d0b8789 Compare February 9, 2022 05:43
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tsipa commented Feb 9, 2022

Master branch: 3caa7d2
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from d0b8789 to d4e9214 Compare February 9, 2022 05:51
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tsipa commented Feb 9, 2022

Master branch: dc37dc6
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from d4e9214 to ebaafb4 Compare February 9, 2022 13:41
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tsipa commented Feb 9, 2022

Master branch: e531396
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from ebaafb4 to d119788 Compare February 9, 2022 20:02
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tsipa commented Feb 10, 2022

Master branch: 1127170
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from d119788 to e939276 Compare February 10, 2022 05:22
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tsipa commented Feb 10, 2022

Master branch: 85fbd23
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from e939276 to 13623db Compare February 10, 2022 22:38
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tsipa commented Feb 11, 2022

Master branch: a5a358a
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 13623db to 5c4fec0 Compare February 11, 2022 01:56
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tsipa commented Feb 11, 2022

Master branch: 4cc0991
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 5c4fec0 to ec7784b Compare February 11, 2022 03:04
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tsipa commented Feb 11, 2022

Master branch: 4407fa0
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from ec7784b to 49c34e0 Compare February 11, 2022 05:19
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tsipa commented Feb 11, 2022

Master branch: d130e95
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 49c34e0 to 8ff730a Compare February 11, 2022 21:02
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tsipa commented Feb 12, 2022

Master branch: 9c3de61
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 8ff730a to 9210bdb Compare February 12, 2022 16:10
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tsipa commented Feb 15, 2022

Master branch: edc21dc
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 9210bdb to 2a50cd6 Compare February 15, 2022 17:27
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tsipa commented Feb 15, 2022

Master branch: d2b94f3
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 2a50cd6 to 925fe58 Compare February 15, 2022 18:09
Nobody and others added 3 commits February 15, 2022 10:12
adding ci files
9dae90c
arm64: move AARCH64_BREAK_FAULT into insn-def.h
24c5a0f 
If CONFIG_ARM64_LSE_ATOMICS is off, encoders for LSE-related instructions
can return AARCH64_BREAK_FAULT directly in insn.h. In order to access
AARCH64_BREAK_FAULT in insn.h, we can not include debug-monitors.h in
insn.h, because debug-monitors.h has already depends on insn.h, so just
move AARCH64_BREAK_FAULT into insn-def.h.

It will be used by the following patch to eliminate unnecessary LSE-related
encoders when CONFIG_ARM64_LSE_ATOMICS is off.

Signed-off-by: Hou Tao <houtao1@huawei.com>
arm64: insn: add encoders for atomic operations
f87aa95 
It is a preparation patch for eBPF atomic supports under arm64. eBPF
needs support atomic[64]_fetch_add, atomic[64]_[fetch_]{and,or,xor} and
atomic[64]_{xchg|cmpxchg}. The ordering semantics of eBPF atomics are
the same with the implementations in linux kernel.

Add three helpers to support LDCLR/LDEOR/LDSET/SWP, CAS and DMB
instructions. STADD/STCLR/STEOR/STSET are simply encoded as aliases for
LDADD/LDCLR/LDEOR/LDSET with XZR as the destination register, so no extra
helper is added. atomic_fetch_add() and other atomic ops needs support for
STLXR instruction, so extend enum aarch64_insn_ldst_type to do that.

LDADD/LDEOR/LDSET/SWP and CAS instructions are only available when LSE
atomics is enabled, so just return AARCH64_BREAK_FAULT directly in
these newly-added helpers if CONFIG_ARM64_LSE_ATOMICS is disabled.

Signed-off-by: Hou Tao <houtao1@huawei.com>
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tsipa commented Feb 15, 2022

Master branch: 8cbf062
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=611843
version: 3

Hou Tao added 2 commits February 15, 2022 10:12
bpf, arm64: support more atomic operations
2ebc00b 
Atomics for eBPF patch series adds support for atomic[64]_fetch_add,
atomic[64]_[fetch_]{and,or,xor} and atomic[64]_{xchg|cmpxchg}, but
it only adds support for x86-64, so support these atomic operations
for arm64 as well.

Basically the implementation procedure is almost mechanical translation
of code snippets in atomic_ll_sc.h & atomic_lse.h & cmpxchg.h located
under arch/arm64/include/asm.

When LSE atomic is unavailable, an extra temporary register is needed for
(BPF_ADD | BPF_FETCH) to save the value of src register, instead of adding
TMP_REG_4 just use BPF_REG_AX instead. Also make emit_lse_atomic() as an
empty inline function when CONFIG_ARM64_LSE_ATOMICS is disabled.

For cpus_have_cap(ARM64_HAS_LSE_ATOMICS) case and no-LSE-ATOMICS case, the
following three tests: "./test_verifier", "./test_progs -t atomic" and
"insmod ./test_bpf.ko" are exercised and passed.

Signed-off-by: Hou Tao <houtao1@huawei.com>
selftests/bpf: use raw_tp program for atomic test
9d5b5d4 
Now atomic tests will attach fentry program and run it through
bpf_prog_test_run_opts(), but attaching fentry program depends on bpf
trampoline which is only available under x86-64. Considering many archs
have atomic support, using raw_tp program instead.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
@tsipa tsipa force-pushed the series/611843=>bpf-next branch from 925fe58 to 9d5b5d4 Compare February 15, 2022 18:13
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