From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1E6651B78F3 for ; Wed, 27 May 2026 05:58:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779861482; cv=none; b=pY5i92V3dV7sCP4oP0In+jHQxBaK5Nj40SLw0Q3I6QC8hZMezQOo2wRN+HGoSlH9TzX+QtKbTRv8VfLu1ztmZEOijzHKcied5UgMhQhJ7Gd+sydy5zhzJpuTyAtCQSgzqM0kx3DzyVABueaL1MXt1hMQU6yroU4ZXLFZ/2r7wv4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779861482; c=relaxed/simple; bh=Ds858C8JSlwFv9V0HFpdGWu5Lwj48IBa8qLqXCeXhAY=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=SnWtkWsPY8Oddy06Pzg7rPyjqnpYy1YIPfeu6uYLn/s5HZ8IzDFHlZVJhkmTnwcY+5DSxyy4Q+nymvqAuYEEvWSCEe0Dbhyd+NWhAF09RbNiauJ/zerMboAYpYCpGGdgMrtBYzKg9kdP9tv54SleFr4lJeYk3MJT1qNYoWNRyCY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--aliceryhl.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=BlOmG/n3; arc=none smtp.client-ip=209.85.128.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--aliceryhl.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="BlOmG/n3" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-48d127eb013so54125955e9.1 for ; Tue, 26 May 2026 22:58:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1779861479; x=1780466279; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=QL+f4AZjX4KECcd9eray4sdH5Ebp4GC/Yod4j5/Zhjg=; b=BlOmG/n3CW7KU+Owp2zMH4yWG3mALcdjcy4JFYNgcC6JHWYsJh6O5hrh9WfP35W0k/ JiaOywqLFv07Iz0r+BY297tnyHUio885FaRJ5T/xOzUo/qyN2lc7cjMWci5DW9bEo3Yc QBhbHvWmbXhozaY6Q2eRJVY4TYWraZciyhzc9dGq4Si3UKtthpKj2PKeqIAzGjN4t42q dce77sT6/MUyME0ZmQSVi4m263rzW+2mTJO3Ja71ozbliQRjQ+/ixPyn/zYPEAObi4RP iekk1l+tpeI6qbHxjrk3K1YAQGSioCFILF/ynVbGJnI/hFRBvF4Pi/kFfxv9OcQ5cBYG idzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779861479; x=1780466279; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=QL+f4AZjX4KECcd9eray4sdH5Ebp4GC/Yod4j5/Zhjg=; b=TWzIi4BZOSxVBtp7aSq/+o79tufLO1EQkdQ4wuT7b87gPWKMYd8IxDMrbbJZbKNHrN HlZh5oWF4Y142x+81lZVJX28PwcnIaezQhfA5EMV6BeOTT45pU3j3Yawu1aeLcJgLzNW TWDHdOBcIeGP0G3EWrzfpU8gcW3kSQUqYDr+5mAK43pmPcsdlEWyCNiNPuwyhtAAtsZx DoFu1Tb9bumWUs3i5eYe6CP+xMwb3WIQoJ+CxIUa8/1Y+Zl+hRTZb3Yd5Lp2suU+8w/t P8XsaBwlSn6pXh2T7pLlxA8WGI2g6z7QmtSkt8nOezWzm1Y4D58FrSqUqTGzsRsT/ryp 2H4w== X-Forwarded-Encrypted: i=1; AFNElJ/tVu0cNiTJW2q7DV+HOkjLDR/jHO56TCjBNk6Xrwgbgctz3fcvmeNgXsnZnO/gXx8UB/MZdxGD6Mwt@vger.kernel.org X-Gm-Message-State: AOJu0YxvdL3R3tXdxgjQmju9jshhE8BLD/dnRFU8Hl+5Og2mqrpsc/u/ MepEXMuceilLsQZPKhpfmVIe2VD6Uoxjt0j3YTqTPAnV+98/gtk3SX81ikr7Lb9vcMreGitF7tj BsEf1dWYmbA2SB6nP/g== X-Received: from wmql4.prod.google.com ([2002:a05:600c:4f04:b0:490:3c15:7144]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:c168:b0:48a:6798:52e9 with SMTP id 5b1f17b1804b1-49042268d98mr377878395e9.0.1779861479469; Tue, 26 May 2026 22:57:59 -0700 (PDT) Date: Wed, 27 May 2026 05:57:58 +0000 In-Reply-To: <20260521165622.279953-3-japo@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260521165622.279953-1-japo@linux.ibm.com> <20260521165622.279953-3-japo@linux.ibm.com> Message-ID: Subject: Re: [PATCH v3 2/4] s390/jump_label: Implement ARCH_STATIC_BRANCH_JUMP_ASM and ARCH_STATIC_BRANCH_ASM macros From: Alice Ryhl To: Jan Polensky Cc: hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, ojeda@kernel.org, peterz@infradead.org, jpoimboe@kernel.org, jbaron@akamai.com, borntraeger@linux.ibm.com, svens@linux.ibm.com, boqun@kernel.org, gary@garyguo.net, bjorn3_gh@protonmail.com, lossin@kernel.org, a.hindborg@kernel.org, tmgross@umich.edu, dakr@kernel.org, rostedt@goodmis.org, ardb@kernel.org, linux-s390@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" On Thu, May 21, 2026 at 06:56:20PM +0200, Jan Polensky wrote: > Rust static branch support needs the s390 jump label instruction sequence > and __jump_table emission in a reusable form. The current implementation > embeds the sequence directly in the C asm goto blocks, which cannot be > shared with Rust. > > Introduce ARCH_STATIC_BRANCH_ASM and ARCH_STATIC_BRANCH_JUMP_ASM to > describe the brcl sequences for the likely-false and likely-true cases > and to emit the same __jump_table entries as before. Switch the existing > C helpers to use the new macros to avoid duplication without changing > the generated code. > > Signed-off-by: Jan Polensky This looks right. Reviewed-by: Alice Ryhl Did you test it? Alice