From patchwork Fri Dec 22 19:35:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Graf X-Patchwork-Id: 13503729 Received: from smtp-fw-80006.amazon.com (smtp-fw-80006.amazon.com [99.78.197.217]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B3F572C84B; Fri, 22 Dec 2023 19:36:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=amazon.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="fK8T2oo1" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1703273797; x=1734809797; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=V6Ou6SwquM+raA1qs66DJzmcDcyVj924rceIRas5lS8=; b=fK8T2oo1NrusDyl9JTVbXJW76JITugWDsgjqinDOoBbi9PxWyyiMZfJ3 q5FyXj/DzwLKJUE4SDlEKW/uHZv+dFSNU/WmVl+RcBV9Oz1O/W0cFBOYX JUWMFT/XBoC8LQtAEpTJ6Hxv4YjKYOQl61OkrH+TTMRzgXVKsdoxY+P9R k=; X-IronPort-AV: E=Sophos;i="6.04,297,1695686400"; d="scan'208";a="261444389" Received: from pdx4-co-svc-p1-lb2-vlan3.amazon.com (HELO email-inbound-relay-iad-1a-m6i4x-96feee09.us-east-1.amazon.com) ([10.25.36.214]) by smtp-border-fw-80006.pdx80.corp.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Dec 2023 19:36:34 +0000 Received: from smtpout.prod.us-west-2.prod.farcaster.email.amazon.dev (iad7-ws-svc-p70-lb3-vlan2.iad.amazon.com [10.32.235.34]) by email-inbound-relay-iad-1a-m6i4x-96feee09.us-east-1.amazon.com (Postfix) with ESMTPS id 9FF3949A6D; Fri, 22 Dec 2023 19:36:22 +0000 (UTC) Received: from EX19MTAUWB002.ant.amazon.com [10.0.21.151:35389] by smtpin.naws.us-west-2.prod.farcaster.email.amazon.dev [10.0.24.220:2525] with esmtp (Farcaster) id 9ed8fb9a-78f6-45ad-a602-e555218674d3; Fri, 22 Dec 2023 19:36:21 +0000 (UTC) X-Farcaster-Flow-ID: 9ed8fb9a-78f6-45ad-a602-e555218674d3 Received: from EX19D020UWC004.ant.amazon.com (10.13.138.149) by EX19MTAUWB002.ant.amazon.com (10.250.64.231) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Fri, 22 Dec 2023 19:36:21 +0000 Received: from dev-dsk-graf-1a-5ce218e4.eu-west-1.amazon.com (10.253.83.51) by EX19D020UWC004.ant.amazon.com (10.13.138.149) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Fri, 22 Dec 2023 19:36:17 +0000 From: Alexander Graf To: CC: , , , , , , , Eric Biederman , "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , "Rob Herring" , Steven Rostedt , "Andrew Morton" , Mark Rutland , "Tom Lendacky" , Ashish Kalra , James Gowans , Stanislav Kinsburskii , , , , Anthony Yznaga , Usama Arif , David Woodhouse , Benjamin Herrenschmidt Subject: [PATCH v2 02/17] memblock: Declare scratch memory as CMA Date: Fri, 22 Dec 2023 19:35:52 +0000 Message-ID: <20231222193607.15474-3-graf@amazon.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20231222193607.15474-1-graf@amazon.com> References: <20231222193607.15474-1-graf@amazon.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: EX19D035UWA004.ant.amazon.com (10.13.139.109) To EX19D020UWC004.ant.amazon.com (10.13.138.149) When we finish populating our memory, we don't want to lose the scratch region as memory we can use for useful data. Do do that, we mark it as CMA memory. That means that any allocation within it only happens with movable memory which we can then happily discard for the next kexec. That way we don't lose the scratch region's memory anymore for allocations after boot. Signed-off-by: Alexander Graf --- v1 -> v2: - test bot warning fix --- mm/memblock.c | 30 ++++++++++++++++++++++++++---- 1 file changed, 26 insertions(+), 4 deletions(-) diff --git a/mm/memblock.c b/mm/memblock.c index e89e6c8f9d75..3700c2c1a96d 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -1100,10 +1101,6 @@ static bool should_skip_region(struct memblock_type *type, if ((flags & MEMBLOCK_SCRATCH) && !memblock_is_scratch(m)) return true; - /* Leave scratch memory alone after scratch-only phase */ - if (!(flags & MEMBLOCK_SCRATCH) && memblock_is_scratch(m)) - return true; - return false; } @@ -2153,6 +2150,20 @@ static void __init __free_pages_memory(unsigned long start, unsigned long end) } } +#ifdef CONFIG_MEMBLOCK_SCRATCH +static void reserve_scratch_mem(phys_addr_t start, phys_addr_t end) +{ + ulong start_pfn = pageblock_start_pfn(PFN_DOWN(start)); + ulong end_pfn = pageblock_align(PFN_UP(end)); + ulong pfn; + + for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) { + /* Mark as CMA to prevent kernel allocations in it */ + set_pageblock_migratetype(pfn_to_page(pfn), MIGRATE_CMA); + } +} +#endif + static unsigned long __init __free_memory_core(phys_addr_t start, phys_addr_t end) { @@ -2214,6 +2225,17 @@ static unsigned long __init free_low_memory_core_early(void) memmap_init_reserved_pages(); +#ifdef CONFIG_MEMBLOCK_SCRATCH + /* + * Mark scratch mem as CMA before we return it. That way we ensure that + * no kernel allocations happen on it. That means we can reuse it as + * scratch memory again later. + */ + __for_each_mem_range(i, &memblock.memory, NULL, NUMA_NO_NODE, + MEMBLOCK_SCRATCH, &start, &end, NULL) + reserve_scratch_mem(start, end); +#endif + /* * We need to use NUMA_NO_NODE instead of NODE_DATA(0)->node_id * because in some case like Node0 doesn't have RAM installed