From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6EEADC5DF7D for ; Wed, 19 Aug 2026 01:31:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.sourceforge.net; s=beta; h=Content-Transfer-Encoding:Content-Type:Cc: Reply-To:From:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Subject:MIME-Version:Message-ID:Date:To:Sender: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=GJ7FGKOoHjH2GaTJKbOeyEUXen8m2txATwKzEL0nfaU=; b=EmNxI0YACaNHEboSvhHvyQyj2Q e+jCG1uJpsY75bqWW5Klbg2IsA+ybA3WEka2+faRx5pgwjV3NHMU6+D2xkX4en0ECsg2Ep7QGbGhI UyPZ4GuPV2jJ91trovR5NTabm1VYPMld60THINJ19x+fBoxs4mJCO3XQPoay4cazIaHE=; Received: from [127.0.0.1] (helo=sfs-ml-1.v29.lw.sourceforge.com) by sfs-ml-1.v29.lw.sourceforge.com with esmtp (Exim 4.95) (envelope-from ) id 1wwV9I-0000Er-KD; Wed, 19 Aug 2026 01:31:22 +0000 Received: from [172.30.29.66] (helo=mx.sourceforge.net) by sfs-ml-1.v29.lw.sourceforge.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1wwV9H-0000El-Ec for linux-f2fs-devel@lists.sourceforge.net; Wed, 19 Aug 2026 01:31:20 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=Content-Transfer-Encoding:MIME-Version:Message-ID: Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=ciOwVnry23KD4xHIlyO86z6LID8QhsuqnBX9yi5eszE=; b=gwfsmGOSq1kNWPQATUMq8CX43+ Go4Xm+vpkc3B1zFf1P0KhApi5JxrA67Yz9cEhD0hW2iRAJmpKqK9GG1Yt4/lFSlAbr3RKzFxe9NWR PCk4+Gc8PkIKbQOZxKvppBg1fCklRdIuGjJQeIQbk6Pqk2Eksado69y4jIPiKX5+cpRc=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject:Cc:To:From :Sender:Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Id:List-Help:List-Unsubscribe:List-Subscribe:List-Post: List-Owner:List-Archive; bh=ciOwVnry23KD4xHIlyO86z6LID8QhsuqnBX9yi5eszE=; b=g C8nPTRYSSJWTZX7wgLB5WFNE8mvthKC/FZP/MbrSFnAk3um6B2FpZRywCTNthCsCWXSIUwg7CSnFc 31Oxv0SicZIh2TpFQn2OfdVjrhMtGD2LprzGyMdaW7JRSdlXCCgpn5k3ssTqgYUw+tb0zbpg06rLK llz2Ug3DwkMcajVI=; Received: from sea.source.kernel.org ([172.234.252.31]) by sfi-mx-2.v28.lw.sourceforge.com with esmtps (TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.95) id 1wwV9E-0007R0-7l for linux-f2fs-devel@lists.sourceforge.net; Wed, 19 Aug 2026 01:31:20 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id B192443861 for ; Wed, 19 Aug 2026 01:31:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B31741F000E9; Wed, 19 Aug 2026 01:31:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787103074; bh=ciOwVnry23KD4xHIlyO86z6LID8QhsuqnBX9yi5eszE=; h=From:To:Cc:Subject:Date; b=XLMGESTdWaAUDut0GwT+vc4dOii3mcgi1dwg+xJ8NM9ebLekfyesEVFDITJluG9PA eL6pMxR2NwRiCN/5gb6LvZlw4gYtT8i2Hx91UmJgtto5/D77khR+SQCbHMz79Wx0bh LPdlM3BDRqQrY1oOQo2ZpxVR/ddaKS41Asl249hYTnujvTfKW7vYv4lynPupfAA4wU cVxJZBwT9jg9tDj6K0qtt+oICHqdB4XlqyP2+ycVpbNmttPraLwPi1jVQgzKTzjUK5 cCRWCBgfIURQsrnVph5kUjhRmPvpmHTUKt28ZQWfWuAb+mocFySknpnSZHBUjVc2L2 VzfE8Ns4rVpWg== To: jaegeuk@kernel.org Date: Wed, 19 Aug 2026 09:31:07 +0800 Message-ID: <20260819013107.3542105-1-chao@kernel.org> X-Mailer: git-send-email 2.55.0.737.g08866a6d13-goog MIME-Version: 1.0 X-Headers-End: 1wwV9E-0007R0-7l Subject: [f2fs-dev] [PATCH v3 2/2] f2fs: reduce memory footprint of ino management X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Chao Yu via Linux-f2fs-devel Reply-To: Chao Yu Cc: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net Currently, ino entries for APPEND_INO, UPDATE_INO, TRANS_DIR_INO, and XATTR_DIR_INO allocate a 'struct ino_entry' slab object and attach it to both a list and a radix tree solely for existence checks via f2fs_exist_written_data(). Since these ino types only track binary existence status, we can embed the information directly into radix tree value entries as a bitmap: - The Linux radix tree/XArray supports in-place value entries via xa_mk_value() / xa_to_value(), which tag the least significant bit to store an unallocated integer value of BITS_PER_XA_VALUE bits (BITS_PER_LONG - 1) directly in the slot pointer. - For each inode, (ino / BITS_PER_XA_VALUE) serves as the radix tree slot index, and (ino % BITS_PER_XA_VALUE) is used as the bit offset within the slot's bitmap. For example, when tracking ino = 7: - Before: Allocate a 'struct ino_entry' ({ .ino = 7 }), insert its pointer into the radix tree at index = 7, and link it to im->ino_list. - After: Compute slot_index = 7 / BITS_PER_XA_VALUE (index 0) and bit_offset = 7 % BITS_PER_XA_VALUE (bit 7), then set bit 7 in the value entry via xa_mk_value(bitmap) at index 0, without allocating a slab object or linking to a list. Additionally: - In-place slot updates are performed via radix_tree_replace_slot(), and slots are deleted with radix_tree_delete() once the bitmap is zeroed. - Reorder the ino list enum so ORPHAN_INO and FLUSH_INO (which still require struct ino_entry and list traversal) remain separated, while bitmap-based trees are torn down using xa_destroy(). This eliminates 'struct ino_entry' slab allocations and linked-list tracking for these ino types, significantly reducing memory consumption. Signed-off-by: Chao Yu --- v3: - fix warning reported by syzbot https://lore.kernel.org/linux-f2fs-devel/6a8452e1.dcb60774.13163.0003.GAE@google.com fs/f2fs/checkpoint.c | 99 ++++++++++++++++++++++++++++++++++++++++---- fs/f2fs/f2fs.h | 6 ++- 2 files changed, 95 insertions(+), 10 deletions(-) diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index eb2f955b1e2a..c73999e39a39 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -766,6 +766,64 @@ static void __remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type) spin_unlock(&im->ino_lock); } +static void __set_ino_bitmap(struct f2fs_sb_info *sbi, nid_t ino, int type) +{ + struct inode_management *im = &sbi->im[type]; + unsigned long index = INO_SLOT_INDEX(ino); + unsigned int ofs = INO_BIT_OFFSET(ino); + void **slot, *entry; + unsigned long bitmap = 0; + int ret; + + ret = radix_tree_preload(GFP_NOFS | __GFP_NOFAIL); + f2fs_bug_on(sbi, ret); + + spin_lock(&im->ino_lock); + slot = radix_tree_lookup_slot(&im->ino_root, index); + if (slot) { + entry = radix_tree_deref_slot_protected(slot, &im->ino_lock); + bitmap = xa_to_value(entry); + if (!(bitmap & (1UL << ofs))) { + bitmap |= (1UL << ofs); + entry = xa_mk_value(bitmap); + radix_tree_replace_slot(&im->ino_root, slot, entry); + } + } else { + bitmap |= (1UL << ofs); + entry = xa_mk_value(bitmap); + if (unlikely(radix_tree_insert(&im->ino_root, index, entry))) + f2fs_bug_on(sbi, 1); + } + spin_unlock(&im->ino_lock); + radix_tree_preload_end(); +} + +static void __clear_ino_bitmap(struct f2fs_sb_info *sbi, nid_t ino, int type) +{ + struct inode_management *im = &sbi->im[type]; + unsigned long index = INO_SLOT_INDEX(ino); + unsigned int ofs = INO_BIT_OFFSET(ino); + void **slot, *entry; + unsigned long bitmap; + + spin_lock(&im->ino_lock); + slot = radix_tree_lookup_slot(&im->ino_root, index); + if (slot) { + entry = radix_tree_deref_slot_protected(slot, &im->ino_lock); + bitmap = xa_to_value(entry); + if (bitmap & (1UL << ofs)) + bitmap &= ~(1UL << ofs); + + if (bitmap) { + entry = xa_mk_value(bitmap); + radix_tree_replace_slot(&im->ino_root, slot, entry); + } else { + radix_tree_delete(&im->ino_root, index); + } + } + spin_unlock(&im->ino_lock); +} + static void f2fs_wait_for_inode_record(struct f2fs_sb_info *sbi, int mode) { if (mode != APPEND_INO && mode != UPDATE_INO) @@ -778,8 +836,10 @@ static void f2fs_wait_for_inode_record(struct f2fs_sb_info *sbi, int mode) static void __f2fs_add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, unsigned int devidx, int type) { - /* add new dirty ino entry into list */ - __add_ino_entry(sbi, ino, devidx, type); + if (type <= FLUSH_INO) + __add_ino_entry(sbi, ino, devidx, type); + else + __set_ino_bitmap(sbi, ino, type); } void f2fs_add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type) @@ -789,20 +849,33 @@ void f2fs_add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type) void f2fs_remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type) { - /* remove dirty ino entry from list */ - __remove_ino_entry(sbi, ino, type); + if (type <= FLUSH_INO) + __remove_ino_entry(sbi, ino, type); + else + __clear_ino_bitmap(sbi, ino, type); } -/* mode should be APPEND_INO, UPDATE_INO or TRANS_DIR_INO */ +/* mode should be APPEND_INO, UPDATE_INO, TRANS_DIR_INO and XATTR_DIR_INO */ bool f2fs_exist_written_data(struct f2fs_sb_info *sbi, nid_t ino, int mode) { struct inode_management *im = &sbi->im[mode]; - struct ino_entry *e; + unsigned long index = INO_SLOT_INDEX(ino); + unsigned int ofs = INO_BIT_OFFSET(ino); + void *entry; + unsigned long bitmap; + + f2fs_bug_on(sbi, mode <= FLUSH_INO); spin_lock(&im->ino_lock); - e = radix_tree_lookup(&im->ino_root, ino); + entry = radix_tree_lookup(&im->ino_root, index); + if (!entry) { + spin_unlock(&im->ino_lock); + return false; + } + bitmap = xa_to_value(entry); spin_unlock(&im->ino_lock); - return e ? true : false; + + return bitmap & (1UL << ofs); } void f2fs_release_ino_entry(struct f2fs_sb_info *sbi, bool all) @@ -810,7 +883,7 @@ void f2fs_release_ino_entry(struct f2fs_sb_info *sbi, bool all) struct ino_entry *e, *tmp; int i; - for (i = all ? ORPHAN_INO : APPEND_INO; i < MAX_INO_ENTRY; i++) { + for (i = all ? ORPHAN_INO : FLUSH_INO; i <= FLUSH_INO; i++) { struct inode_management *im = &sbi->im[i]; f2fs_wait_for_inode_record(sbi, i); @@ -824,6 +897,14 @@ void f2fs_release_ino_entry(struct f2fs_sb_info *sbi, bool all) } spin_unlock(&im->ino_lock); } + + for (i = APPEND_INO; i < MAX_INO_ENTRY; i++) { + struct inode_management *im = &sbi->im[i]; + + spin_lock(&im->ino_lock); + xa_destroy(&im->ino_root); + spin_unlock(&im->ino_lock); + } } void f2fs_set_dirty_device(struct f2fs_sb_info *sbi, nid_t ino, diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index c925b9207a37..1b96d8718c5c 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -388,14 +388,18 @@ enum { /* for the list of ino */ enum { ORPHAN_INO, /* for orphan ino list */ + FLUSH_INO, /* for multiple device flushing */ APPEND_INO, /* for append ino list */ UPDATE_INO, /* for update ino list */ TRANS_DIR_INO, /* for transactions dir ino list */ XATTR_DIR_INO, /* for xattr updated dir ino list */ - FLUSH_INO, /* for multiple device flushing */ MAX_INO_ENTRY, /* max. list */ }; +#define INO_BITS_PER_SLOT BITS_PER_XA_VALUE +#define INO_SLOT_INDEX(ino) ((ino) / INO_BITS_PER_SLOT) +#define INO_BIT_OFFSET(ino) ((ino) % INO_BITS_PER_SLOT) + struct ino_entry { struct list_head list; /* list head */ nid_t ino; /* inode number */ -- 2.49.0 _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel