From nobody Mon Feb 9 12:25:30 2026 Received: from mail-yw1-f201.google.com (mail-yw1-f201.google.com [209.85.128.201]) (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 CC6E884A26 for ; Mon, 25 Mar 2024 23:50:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711410624; cv=none; b=PzUptR7EonH+S4b7ro7XSbnW9Vn6OAHl6wPjcMVqgFvbe0RVy6HS1N99y+eOTgD9aZLZP+h/02fzPm6bHgxdG+M/vNPuA9Fr+NhB2XjXcmmE9h5nR4MY9LXoc/JfiM0wTt0MJ82rv/YkJSivojPQWJCj4wvubXReLBC5QimMmpo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711410624; c=relaxed/simple; bh=6xxUCt1k7C+LwXDbzCekm9e6ZfMrsxua/6M5UyPsHns=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=LgFjXUwKO2kp/U0wp5gfR8k99qpHqyRdPWB/mRWzYWlEL+LMZB91JfeFUukYIAYyFJf2Twa90qMNJhxW8pNhr6RFfJ2QHgEsgRUZjX8gmWENa5uKbaQ/H6yEoR+FknwFx0GQBh99WWFezMjdFLPKs0xdIAuBRRINevYk7g1yzZc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--yosryahmed.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=kjRJCKjx; arc=none smtp.client-ip=209.85.128.201 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--yosryahmed.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="kjRJCKjx" Received: by mail-yw1-f201.google.com with SMTP id 00721157ae682-60a03635590so99284487b3.0 for ; Mon, 25 Mar 2024 16:50:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1711410622; x=1712015422; 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=u9fvbqW1pLtPErlE8l2YKQeiKLLE5wFNh7avewbFYWs=; b=kjRJCKjxUN2aU1haa67W+vz+lyNDM3VM4OeLHTfKotzkn3jMo3uakiw2baap7rZ0Bw EN4tb8BK9AaV1Kgpzh2/4PWKOdgnOyXu7gHZQOrn8RGOyH9h8k0Kt0VrBBEOi65PskXs +KM3arrq/7cFfwMDFXFS2UgkzxKMTRe/Dyw00T+zcIrQu/DAk7fmFMQTLCPL6ApyOJ/c Acm2aASX7xFDapHAauKyj7477grt++HAYeEp3H759KS55WxqvnK3bxSMwhd5XoHb5jHG 1c3Be2qgoM42YOAtwyPRcCiHLcePuAidbIfPGrvgBOiIJXxsmLb18j6RCfaarjmDab8o 0d2Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1711410622; x=1712015422; 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=u9fvbqW1pLtPErlE8l2YKQeiKLLE5wFNh7avewbFYWs=; b=tFiM2ZzIqmr1RDPhDJUF0L6CZYjdYWE1icLNADF1MdcY0ewDkJSQ060OZ+OElYvfX2 Db8zU+eSlZF56NsF/0c37Z610IdvbItT9gxYbolLzc2n5u5SywUD0jkQZCr4llkmHdEx gqlnC8AiKsETxH+hOlJ1mE0qHeR/uyO+SVCv/eSdxR4NHZvKJq6yytMbmvETfYNU9TF3 ObihNcuQRF9EYsRQzyQz5sW5BXOUJJJR0O+/PKyIcS37R9gGEP9jae+ZAFhDjPN5xa5z 7nw6GjqIuqf20lnFhsPak6TYISGUahxiJ8rome69WIh21uV3uysWByHrTperuUAbP/7e WTgQ== X-Forwarded-Encrypted: i=1; AJvYcCWt9tYZ/99jf9cxGAk/hMveLz33tk8Tr7YTq07/7M2QHRxNoBysugPv3UZ75WU3mZkTU5ozgBj4aFmO57okx21G1GCVQaN0qTNmKEYE X-Gm-Message-State: AOJu0YyNPivweKkekyZB+VgN7y/b3hYIHF1J8GLqFlJUDLIVxYJCW/rF CAPneKZZM3CqqcXRdw9peoS3+W9QH+twg8wZdRI2F9IpCj5W7dgsVWk8GFzfyMueyHDwaxdGanH PeNNprfbpCaGKIcLn6g== X-Google-Smtp-Source: AGHT+IH+DXWV+vX4OULsfH+Uyq0gzOaLllxrZEK/FYDaAYjBCM9JZ11SOX35Q3oKMnkT3VL0MGvjY9eZ8pU6LA5R X-Received: from yosry.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:29b4]) (user=yosryahmed job=sendgmr) by 2002:a05:6902:2491:b0:dcb:e982:4e40 with SMTP id ds17-20020a056902249100b00dcbe9824e40mr2590953ybb.12.1711410621894; Mon, 25 Mar 2024 16:50:21 -0700 (PDT) Date: Mon, 25 Mar 2024 23:50:09 +0000 In-Reply-To: <20240325235018.2028408-1-yosryahmed@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240325235018.2028408-1-yosryahmed@google.com> X-Mailer: git-send-email 2.44.0.396.g6e790dbe36-goog Message-ID: <20240325235018.2028408-2-yosryahmed@google.com> Subject: [RFC PATCH 1/9] mm: zswap: always shrink in zswap_store() if zswap_pool_reached_full From: Yosry Ahmed To: Andrew Morton Cc: Johannes Weiner , Nhat Pham , Chengming Zhou , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Yosry Ahmed Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The cleanup code in zswap_store() is not pretty, particularly the 'shrink' label at the bottom that ends up jumping between cleanup labels. Instead of having a dedicated label to shrink the pool, just use zswap_pool_reached_full directly to figure out if the pool needs shrinking. zswap_pool_reached_full should be true if and only if the pool needs shrinking. The only caveat is that the value of zswap_pool_reached_full may be changed by concurrent zswap_store() calls between checking the limit and testing zswap_pool_reached_full in the cleanup code. This is fine because: - If zswap_pool_reached_full was true during limit checking then became false during the cleanup code, then someone else already took care of shrinking the pool and there is no need to queue the worker. That would be a good change. - If zswap_pool_reached_full was false during limit checking then became true during the cleanup code, then someone else hit the limit meanwhile. In this case, both threads will try to queue the worker, but it never gets queued more than once anyway. Also, calling queue_work() multiple times when the limit is hit could already happen today, so this isn't a significant change in any way. Signed-off-by: Yosry Ahmed Acked-by: Johannes Weiner Reviewed-by: Chengming Zhou Reviewed-by: Nhat Pham --- mm/zswap.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/mm/zswap.c b/mm/zswap.c index c4979c76d58e3..1cf3ab4b22e64 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -1429,12 +1429,12 @@ bool zswap_store(struct folio *folio) if (cur_pages >=3D max_pages) { zswap_pool_limit_hit++; zswap_pool_reached_full =3D true; - goto shrink; + goto reject; } =20 if (zswap_pool_reached_full) { if (cur_pages > zswap_accept_thr_pages()) - goto shrink; + goto reject; else zswap_pool_reached_full =3D false; } @@ -1540,6 +1540,8 @@ bool zswap_store(struct folio *folio) zswap_entry_cache_free(entry); reject: obj_cgroup_put(objcg); + if (zswap_pool_reached_full) + queue_work(shrink_wq, &zswap_shrink_work); check_old: /* * If the zswap store fails or zswap is disabled, we must invalidate the @@ -1550,10 +1552,6 @@ bool zswap_store(struct folio *folio) if (entry) zswap_entry_free(entry); return false; - -shrink: - queue_work(shrink_wq, &zswap_shrink_work); - goto reject; } =20 bool zswap_load(struct folio *folio) --=20 2.44.0.396.g6e790dbe36-goog