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From: "Alexei Starovoitov" <alexei.starovoitov@gmail.com>
To: "Puranjay Mohan" <puranjay@kernel.org>, <bpf@vger.kernel.org>
Cc: "Daniel Borkmann" <daniel@iogearbox.net>,
	"Andrii Nakryiko" <andrii@kernel.org>,
	"Martin KaFai Lau" <martin.lau@linux.dev>,
	"Eduard Zingerman" <eddyz87@gmail.com>,
	"Kumar Kartikeya Dwivedi" <memxor@gmail.com>,
	"Song Liu" <song@kernel.org>,
	"Yonghong Song" <yonghong.song@linux.dev>,
	"Tejun Heo" <tj@kernel.org>, "David Vernet" <void@manifault.com>,
	"Andrea Righi" <arighi@nvidia.com>,
	"Changwoo Min" <changwoo@igalia.com>, <sched-ext@lists.linux.dev>,
	<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH bpf-next v2 2/3] selftests/bpf: Test fetching AND/OR/XOR atomics in arena
Date: Thu, 24 Sep 2026 16:29:32 +0000	[thread overview]
Message-ID: <DLNOTGX1CRYG.3N0BDEFH1WPQQ@gmail.com> (raw)
In-Reply-To: <20260924160354.531101-3-puranjay@kernel.org>

On Thu, Sep 24, 2026 at 09:03 AM Puranjay Mohan <puranjay@kernel.org> wrote:
> -#ifdef __BPF_FEATURE_ATOMIC_MEM_ORDERING
> -	__c11_atomic_fetch_and(&and64_value, 0x011ull << 32, memory_order_relaxed);
> -	__c11_atomic_fetch_and(&and32_value, 0x011, memory_order_relaxed);
> -#else
> -	__sync_fetch_and_and(&and64_value, 0x011ull << 32);
> -	__sync_fetch_and_and(&and32_value, 0x011);
> -#endif
> +	and64_result = __sync_fetch_and_and(&and64_value, 0x011ull << 32);
> +	and32_result = __sync_fetch_and_and(&and32_value, 0x011);
> +	/* Discarding the result is what selects the non-fetching insn. */
> +	__c11_atomic_fetch_and(&and64_noreturn_value, 0x011ull << 32, memory_order_relaxed);

The 32-bit non-fetching and/or/xor in arena are not tested anymore.
Pls keep them too.

  reply	other threads:[~2026-09-24 16:29 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-09-24 16:03 [PATCH bpf-next v2 0/3] bpf, x86: Support " Puranjay Mohan
2026-09-24 16:03 ` [PATCH bpf-next v2 1/3] " Puranjay Mohan
2026-09-24 16:03 ` [PATCH bpf-next v2 2/3] selftests/bpf: Test " Puranjay Mohan
2026-09-24 16:29   ` Alexei Starovoitov [this message]
2026-09-24 16:55   ` bot+bpf-ci
2026-09-24 16:03 ` [PATCH bpf-next v2 3/3] sched_ext: Stop citing the x86 JIT for the cmask cmpxchg loop Puranjay Mohan
2026-09-24 16:30   ` Alexei Starovoitov
2026-09-24 16:33     ` Puranjay Mohan

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