From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-186.mta0.migadu.com (out-186.mta0.migadu.com [91.218.175.186]) (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 C41002F7EF4 for ; Sat, 27 Jun 2026 07:25:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.186 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782545121; cv=none; b=nBc/6wIgWQQTJs5vVayYli0LSKcDMUuQhCdnuchjMS6jwtJxybMF1LoYD1aB/Z6litj0OUz7bdBuhVIfCV8ElDC1EGCP2ufm7XjE8jiP2n/7QH2NfOwuYEOayUa1Rx/MkgW+wNqmh0Lb4bOEqrNyynO7QvsD/n+5lVwqPf6HtAs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782545121; c=relaxed/simple; bh=E9dU6LGcKZLUNYa+3KP6j9fjS4C3g3agsZStTzFvM+Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pt78Sy9I4+a0kLbh7Pj5HP538eVUy0vr9KyfTUBBxp+s8MU1jmFVnD0ClQT1H0MNHEWCG28sjXHrbj0SjSrNh/TFols3Dd3tfX11WiV7Nw5OSkTAC7xSYlaJXChDi/lCdUNd3V9yoq/ENxcqPc/2g08Q+mfd6HclQyVWEldPDN4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=mFLDYxrL; arc=none smtp.client-ip=91.218.175.186 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="mFLDYxrL" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1782545117; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jYH2dLJwZ3cdQqCNGntqjFRlxZpQAFD5iRYR2M5+uBI=; b=mFLDYxrL7UzOFziiy3W002Tsl27Ys6rVpAkAtTN7GhFfN+EGRWLkUTDlYqR50K6+LYo6l5 K3L7/YS7n8L0JMlaYVk988HcdfDtUwbN1MTF4Dte5n7Mho32m3Y188LRnHLaIFnN/7unqA Oj9MWBWemhL4V5W4bxZL5DpOGcwAxEE= From: Qi Zheng To: akpm@linux-foundation.org, david@kernel.org, ljs@kernel.org, ziy@nvidia.com, baolin.wang@linux.alibaba.com, liam@infradead.org, npache@redhat.com, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, lance.yang@linux.dev, muchun.song@linux.dev, osalvador@suse.de, chrisl@kernel.org, kasong@tencent.com, shikemeng@huaweicloud.com, nphamcs@gmail.com, baoquan.he@linux.dev, youngjun.park@lge.com, peterx@redhat.com, usama.arif@linux.dev, willy@infradead.org, vbabka@kernel.org, surenb@google.com, mhocko@suse.com, jackmanb@google.com, hannes@cmpxchg.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Qi Zheng Subject: [RFC PATCH 5/8] mm: add reserved THP vma flag Date: Sat, 27 Jun 2026 15:21:53 +0800 Message-ID: In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: Qi Zheng Introduce the VM_RESERVED_THP VMA flag to mark Virtual Memory Areas (VMAs) that have the reserved THP policy enabled. Also, add the "rt" (reserved THP) flag indicator to the output of /proc//smaps to facilitate monitoring and debugging the status of the corresponding VMAs from userspace. Signed-off-by: Qi Zheng --- fs/proc/task_mmu.c | 3 +++ include/linux/mm.h | 7 +++++++ tools/testing/vma/include/dup.h | 1 + 3 files changed, 11 insertions(+) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index d32408f7cd5ed..65c4b2a61aeac 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1245,6 +1245,9 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) #endif #ifdef CONFIG_64BIT [ilog2(VM_SEALED)] = "sl", +#endif +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + [ilog2(VM_RESERVED_THP)] = "rt", #endif }; size_t i; diff --git a/include/linux/mm.h b/include/linux/mm.h index 485df9c2dbddb..278cf4bfd4ec5 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -353,6 +353,7 @@ enum { #endif DECLARE_VMA_BIT(UFFD_MINOR, 41), DECLARE_VMA_BIT(SEALED, 42), + DECLARE_VMA_BIT(RESERVED_THP, 43), /* Flags that reuse flags above. */ DECLARE_VMA_BIT_ALIAS(PKEY_BIT0, HIGH_ARCH_0), DECLARE_VMA_BIT_ALIAS(PKEY_BIT1, HIGH_ARCH_1), @@ -526,6 +527,12 @@ enum { #define VMA_DROPPABLE EMPTY_VMA_FLAGS #endif +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#define VM_RESERVED_THP INIT_VM_FLAG(RESERVED_THP) +#else +#define VM_RESERVED_THP VM_NONE +#endif + /* Bits set in the VMA until the stack is in its final location */ #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ | VM_STACK_EARLY) diff --git a/tools/testing/vma/include/dup.h b/tools/testing/vma/include/dup.h index cf73bcd9bb9d5..022b7a56b6a9f 100644 --- a/tools/testing/vma/include/dup.h +++ b/tools/testing/vma/include/dup.h @@ -160,6 +160,7 @@ enum { #endif DECLARE_VMA_BIT(UFFD_MINOR, 41), DECLARE_VMA_BIT(SEALED, 42), + DECLARE_VMA_BIT(RESERVED_THP, 43), /* Flags that reuse flags above. */ DECLARE_VMA_BIT_ALIAS(PKEY_BIT0, HIGH_ARCH_0), DECLARE_VMA_BIT_ALIAS(PKEY_BIT1, HIGH_ARCH_1), -- 2.54.0