public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: "Paul E. McKenney" <paulmck@kernel.org>
To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
	lkmm@lists.linux.dev, kernel-team@meta.com, mingo@kernel.org
Cc: stern@rowland.harvard.edu, parri.andrea@gmail.com,
	will@kernel.org, peterz@infradead.org, boqun.feng@gmail.com,
	npiggin@gmail.com, dhowells@redhat.com, j.alglave@ucl.ac.uk,
	luc.maranget@inria.fr, akiyks@gmail.com,
	Puranjay Mohan <puranjay@kernel.org>,
	"Paul E . McKenney" <paulmck@kernel.org>,
	Daniel Lustig <dlustig@nvidia.com>,
	Joel Fernandes <joel@joelfernandes.org>
Subject: [PATCH memory-model 2/7] tools/memory-model: Add atomic_andnot() with its variants
Date: Thu, 20 Feb 2025 08:13:58 -0800	[thread overview]
Message-ID: <20250220161403.800831-2-paulmck@kernel.org> (raw)
In-Reply-To: <8cfb51e3-9726-4285-b8ca-0d0abcacb07e@paulmck-laptop>

From: Puranjay Mohan <puranjay@kernel.org>

Pull-855[1] added the support of atomic_andnot() to the herd tool. Use
this to add the implementation in the LKMM. All of the ordering variants
are also added.

Here is a small litmus-test that uses this operation:

C andnot

{
atomic_t u = ATOMIC_INIT(7);
}

P0(atomic_t *u)
{

        r0 = atomic_fetch_andnot(3, u);
        r1 = READ_ONCE(*u);
}

exists (0:r0=7 /\ 0:r1=4)

Test andnot Allowed
States 1
0:r0=7; 0:r1=4;
Ok
Witnesses
Positive: 1 Negative: 0
Condition exists (0:r0=7 /\ 0:r1=4)
Observation andnot Always 1 0
Time andnot 0.00
Hash=78f011a0b5a0c65fa1cf106fcd62c845

[1] https://github.com/herd/herdtools7/pull/855

Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Acked-by: Andrea Parri <parri.andrea@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Will Deacon <will@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Daniel Lustig <dlustig@nvidia.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: <linux-arch@vger.kernel.org>
---
 tools/memory-model/linux-kernel.def | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/tools/memory-model/linux-kernel.def b/tools/memory-model/linux-kernel.def
index d1f11930ec512..a12b96c547b7a 100644
--- a/tools/memory-model/linux-kernel.def
+++ b/tools/memory-model/linux-kernel.def
@@ -70,6 +70,7 @@ atomic_or(V,X)  { __atomic_op(X,|,V); }
 atomic_xor(V,X) { __atomic_op(X,^,V); }
 atomic_inc(X)   { __atomic_op(X,+,1); }
 atomic_dec(X)   { __atomic_op(X,-,1); }
+atomic_andnot(V,X) { __atomic_op(X,&~,V); }
 
 atomic_add_return(V,X) __atomic_op_return{mb}(X,+,V)
 atomic_add_return_relaxed(V,X) __atomic_op_return{once}(X,+,V)
@@ -138,3 +139,8 @@ atomic_add_negative(V,X) __atomic_op_return{mb}(X,+,V) < 0
 atomic_add_negative_relaxed(V,X) __atomic_op_return{once}(X,+,V) < 0
 atomic_add_negative_acquire(V,X) __atomic_op_return{acquire}(X,+,V) < 0
 atomic_add_negative_release(V,X) __atomic_op_return{release}(X,+,V) < 0
+
+atomic_fetch_andnot(V,X) __atomic_fetch_op{mb}(X,&~,V)
+atomic_fetch_andnot_acquire(V,X) __atomic_fetch_op{acquire}(X,&~,V)
+atomic_fetch_andnot_release(V,X) __atomic_fetch_op{release}(X,&~,V)
+atomic_fetch_andnot_relaxed(V,X) __atomic_fetch_op{once}(X,&~,V)
-- 
2.40.1


  parent reply	other threads:[~2025-02-20 16:14 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-02-20 16:13 [PATCH memory-model 0/7] LKMM updates for v6.15 Paul E. McKenney
2025-02-20 16:13 ` [PATCH memory-model 1/7] tools/memory-model: Add atomic_and()/or()/xor() and add_negative Paul E. McKenney
2025-02-20 16:13 ` Paul E. McKenney [this message]
2025-02-20 16:13 ` [PATCH memory-model 3/7] tools/memory-model: Legitimize current use of tags in LKMM macros Paul E. McKenney
2025-02-20 16:14 ` [PATCH memory-model 4/7] tools/memory-model: Define applicable tags on operation in tools/ Paul E. McKenney
2025-02-20 16:14 ` [PATCH memory-model 5/7] tools/memory-model: Define effect of Mb tags on RMWs " Paul E. McKenney
2025-02-20 16:14 ` [PATCH memory-model 6/7] tools/memory-model: Switch to softcoded herd7 tags Paul E. McKenney
2025-02-25  4:24   ` Akira Yokosawa
2025-02-25  7:40     ` Hernan Ponce de Leon
2025-02-20 16:14 ` [PATCH memory-model 7/7] tools/memory-model: Distinguish between syntactic and semantic tags Paul E. McKenney
2025-02-25  4:28   ` Akira Yokosawa
2025-02-25 18:18     ` Paul E. McKenney
  -- strict thread matches above, loose matches on Subject: below --
2024-08-02  0:22 [PATCH memory-model 0/7] LKMM updates for v6.12 Paul E. McKenney
2024-08-02  0:22 ` [PATCH memory-model 2/7] tools/memory-model: Add atomic_andnot() with its variants Paul E. McKenney

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20250220161403.800831-2-paulmck@kernel.org \
    --to=paulmck@kernel.org \
    --cc=akiyks@gmail.com \
    --cc=boqun.feng@gmail.com \
    --cc=dhowells@redhat.com \
    --cc=dlustig@nvidia.com \
    --cc=j.alglave@ucl.ac.uk \
    --cc=joel@joelfernandes.org \
    --cc=kernel-team@meta.com \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lkmm@lists.linux.dev \
    --cc=luc.maranget@inria.fr \
    --cc=mingo@kernel.org \
    --cc=npiggin@gmail.com \
    --cc=parri.andrea@gmail.com \
    --cc=peterz@infradead.org \
    --cc=puranjay@kernel.org \
    --cc=stern@rowland.harvard.edu \
    --cc=will@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox