From nobody Tue Feb 10 04:12:23 2026 Received: from mail-pj1-f74.google.com (mail-pj1-f74.google.com [209.85.216.74]) (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 28FD517A303 for ; Sat, 8 Mar 2025 03:46:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741405598; cv=none; b=Ym7x9EQYUcGSkd7lCEqT0cdqdSDedN0/kVGchC3IgGBk6a2LwG7Qm/3KDSbjojayjdTU6TIce8QDCPV++iJm+QuyRKZ2g/3fG2xU366rSCGm8SI70EJRtLtOD98mqxC6b/CpdQf5OWuvBlBX5e/NyztH2MSGSpnKSh3NaVFgK60= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741405598; c=relaxed/simple; bh=NI9X3DgbmxaxolEB+CWeMI2e6PnbwQP48nhp90OwwL4=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=j7sccr92jdgMYQruTocKyWRgCCJoZJeAYpwKogj79wmSvckvC9TbcLdyksj37CJ/xB3SRjd3FL2d6YltKD0pw1vK4wQtI8rAhkisIkmwoDWiq7Jrb8pCJO2yMamSWbehtV/M55UM/Kwh2iih8s5/JogrkMuKyU8yxpt827sHSuI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--liumartin.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=28TNrnVK; arc=none smtp.client-ip=209.85.216.74 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--liumartin.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="28TNrnVK" Received: by mail-pj1-f74.google.com with SMTP id 98e67ed59e1d1-2ff6943febeso4095737a91.0 for ; Fri, 07 Mar 2025 19:46:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1741405596; x=1742010396; 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=wwsW/fsMcg9hrgcDTPBIA7gFDpTcqMoDXdqlqDc9hnc=; b=28TNrnVKTu9M6VyNHTPFufBtewo0ym7vgZs5rk7FTTZ5PvdkvsJaE1IYAaY9XxCsvN 63uifaSaSCZlW7bbiF6qCvYASW+GkdXznXoIjpMtvgRlDHhLRX/t1fZ1EBT69E0iAxBl s1ykV3KE4rDO8b5kV6s8R8yZ0QDOJj98EcUyv4MF4h8PcQ+Ta71cxEJgtVpZEG2SnTSX rWd0vaOhcoQ0uKYyINrPEKjPIwVZIMF+aqHdfZISA3NZK/mT2ZyPwkKa/X3qoESO4zR9 DXpNfochfIBrEKB6MoQnvBMkQ2TkypAIxnkELg+fl/m7t/V22zrcCKSN1ZDmtF8ByNVr wa4g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1741405596; x=1742010396; 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=wwsW/fsMcg9hrgcDTPBIA7gFDpTcqMoDXdqlqDc9hnc=; b=Xk/vq9vaH/YKCblrkXGM9E7rVMCvhFqS0v1iFMEJesKPaSzpre05BzBEAHMsSV0yI5 Q2RIVSDY0Eez2+lpeK0FXjeuAUr8bY9Jr2WH5DnsZMr6z+qxl/sn/1paApdQNT3zMj/J /i8eMWVhwXB/+ewiHPE/+8WjFtOcQQr8seOzcofaaDYuqAT1AfzbLDIS069gIM7UpS90 79CQA/Hm4/hiunbFN5CSfT2V3nUkbUclSz6+4jLAwXdhAWmUdJindh3HOylX/8cg33HD FrjSf+AsqfGS2OsgWhL1KR52JvbrK87kazfJdPJG+pnaivjBrgCeQCOhOp2YYOqrV149 6wYA== X-Forwarded-Encrypted: i=1; AJvYcCVEshqxccqr/1vXM/9VgqCGrh4OzH2s9mHpskIys5yQf5e3+q8XvrDfD2AuhJ3cxap2WWcv/8PMMO4TeTE=@vger.kernel.org X-Gm-Message-State: AOJu0YzCj6NKVvdi/wiJ+lRhK9EfaSrSp0CYWh2t6eQoApkcmxsIckGA BblvtoEF4E9/3C3PWhHN6pU6e88BaGKq4mk6V/3vsp5hWFtE8nc9Vg8usXIhxds6/ANiecfX/os K7JX4OCXR4dTimw== X-Google-Smtp-Source: AGHT+IHRnkN6wrQOrKWkYrcoXo9vtRqSQ8tpu752H1VzwAoAmAJAj3Fmg6NgVlqukZi3r99JBHgGyN9zS8N/9j0= X-Received: from pjur14.prod.google.com ([2002:a17:90a:d40e:b0:2fc:e37d:85dc]) (user=liumartin job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:254b:b0:2ff:5267:e7da with SMTP id 98e67ed59e1d1-2ffbc1468f9mr3198164a91.3.1741405596445; Fri, 07 Mar 2025 19:46:36 -0800 (PST) Date: Sat, 8 Mar 2025 03:46:02 +0000 In-Reply-To: <20250308034606.2036033-1-liumartin@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250308034606.2036033-1-liumartin@google.com> X-Mailer: git-send-email 2.49.0.rc0.332.g42c0ae87b1-goog Message-ID: <20250308034606.2036033-4-liumartin@google.com> Subject: [PATCH v2 3/3] mm/page_alloc: Add trace event for totalreserve_pages calculation From: Martin Liu To: Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Andrew Morton Cc: Martin Liu , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-mm@kvack.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" This commit introduces a new trace event, `mm_calculate_totalreserve_pages`, which reports the new reserve value at the exact time when it takes effect. The `totalreserve_pages` value represents the total amount of memory reserved across all zones and nodes in the system. This reserved memory is crucial for ensuring that critical kernel operations have access to sufficient memory, even under memory pressure. By tracing the `totalreserve_pages` value, developers can gain insights that how the total reserved memory changes over time. Signed-off-by: Martin Liu Acked-by: David Rientjes --- include/trace/events/kmem.h | 18 ++++++++++++++++++ mm/page_alloc.c | 1 + 2 files changed, 19 insertions(+) diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h index 9623e68d4d26..f74925a6cf69 100644 --- a/include/trace/events/kmem.h +++ b/include/trace/events/kmem.h @@ -402,6 +402,24 @@ TRACE_EVENT(mm_setup_per_zone_lowmem_reserve, __entry->lowmem_reserve) ); =20 +TRACE_EVENT(mm_calculate_totalreserve_pages, + + TP_PROTO(unsigned long totalreserve_pages), + + TP_ARGS(totalreserve_pages), + + TP_STRUCT__entry( + __field(unsigned long, totalreserve_pages) + ), + + TP_fast_assign( + __entry->totalreserve_pages =3D totalreserve_pages; + ), + + TP_printk("totalreserve_pages=3D%lu", __entry->totalreserve_pages) +); + + /* * Required for uniquely and securely identifying mm in rss_stat tracepoin= t. */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e472b1275166..69ceab250979 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5827,6 +5827,7 @@ static void calculate_totalreserve_pages(void) } } totalreserve_pages =3D reserve_pages; + trace_mm_calculate_totalreserve_pages(totalreserve_pages); } =20 /* --=20 2.49.0.rc0.332.g42c0ae87b1-goog