From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 2647FBE4F for ; Fri, 1 Nov 2024 00:20:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730420446; cv=none; b=j3S178eVzFTBml9+2szvSD8D2Dd/DTUSB5CYAZCRD2lVm9Ksy3ysxTp64nHwI8QKAjF8Wxb/ihkTTPB/xMOu2Jdw/Dh36WR7EURQd4Feiz2R/HMLxYJQapYygficakI5GUdM5lZJartX69erTiMz/IQssHgmIDHR3zxqUX8Yyeg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730420446; c=relaxed/simple; bh=e6i0QHMATPCRfmC+70yrheIzk/61hB9FQJkqNKpNKDE=; h=Date:To:From:Subject:Message-Id; b=XCicVe3YJDd+kXiaMn3fmVPWM7ZnIhh3VebiiKRAawlsYQTJCCExNmuyb6v37X3MkGEY3OizBJQvz2TLQEselvNjKE9oNPOG3GVTkF3U9Hs8VwO4tAAIfI63EEVbCMO01vod8r996GrqGtM8HVNibAcx89TfRf4lu7V+BsN0j0c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=jzd8BnZo; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="jzd8BnZo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DA077C4CECF; Fri, 1 Nov 2024 00:20:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1730420445; bh=e6i0QHMATPCRfmC+70yrheIzk/61hB9FQJkqNKpNKDE=; h=Date:To:From:Subject:From; b=jzd8BnZoZQW1P1Vj9/1ELmW2+qXtuWm1VN5dICPqcp04CEwHmkMUYabdCDKaeQwqt bsileL2vj4wUenoWSrc7tUjyl8A5VuSCVWzgJN+pevKNHzMUbWNPZKeeOSBLcUpl5J 60bvlX8fpkpoJv68NCbPdw0N11YHGzhUWmavADRE= Date: Thu, 31 Oct 2024 17:20:45 -0700 To: mm-commits@vger.kernel.org,sidhartha.kumar@oracle.com,lorenzo.stoakes@oracle.com,Liam.Howlett@Oracle.com,richard.weiyang@gmail.com,akpm@linux-foundation.org From: Andrew Morton Subject: + maple_tree-refine-mas_store_root-on-storing-null.patch added to mm-unstable branch Message-Id: <20241101002045.DA077C4CECF@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: maple_tree: refine mas_store_root() on storing NULL has been added to the -mm mm-unstable branch. Its filename is maple_tree-refine-mas_store_root-on-storing-null.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/maple_tree-refine-mas_store_root-on-storing-null.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Wei Yang Subject: maple_tree: refine mas_store_root() on storing NULL Date: Thu, 31 Oct 2024 23:16:26 +0000 Currently, when storing NULL on mas_store_root(), the behavior could be improved. For example possible cases are: * store NULL at any range result a new node * store NULL at range [m, n] where m > 0 to a single entry tree result a new node with range [m, n] set to NULL * store NULL at range [m, n] where m > 0 to an empty tree result consecutive NULL slot * it allows for multiple NULL entries by expanding root to store NULLs to an empty tree This patch tries to improve in: * memory efficient by setting to empty tree instead of using a node * remove the possibility of consecutive NULL slot which will prohibit extended null in later operation Link: https://lkml.kernel.org/r/20241031231627.14316-5-richard.weiyang@gmail.com Signed-off-by: Wei Yang Reviewed-by: Liam R. Howlett Cc: Liam R. Howlett Cc: Sidhartha Kumar Cc: Lorenzo Stoakes Signed-off-by: Andrew Morton --- lib/maple_tree.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) --- a/lib/maple_tree.c~maple_tree-refine-mas_store_root-on-storing-null +++ a/lib/maple_tree.c @@ -3447,9 +3447,20 @@ static inline void mas_root_expand(struc return; } +/* + * mas_store_root() - Storing value into root. + * @mas: The maple state + * @entry: The entry to store. + * + * There is no root node now and we are storing a value into the root - this + * function either assigns the pointer or expands into a node. + */ static inline void mas_store_root(struct ma_state *mas, void *entry) { - if (likely((mas->last != 0) || (mas->index != 0))) + if (!entry) { + if (!mas->index) + rcu_assign_pointer(mas->tree->ma_root, NULL); + } else if (likely((mas->last != 0) || (mas->index != 0))) mas_root_expand(mas, entry); else if (((unsigned long) (entry) & 3) == 2) mas_root_expand(mas, entry); _ Patches currently in -mm which might be from richard.weiyang@gmail.com are mm-mlock-set-the-correct-prev-on-failure.patch maple_tree-i-is-always-less-than-or-equal-to-mas_end.patch maple_tree-goto-complete-directly-on-a-pivot-of-0.patch maple_tree-remove-maple_big_nodeparent.patch maple_tree-memset-maple_big_node-as-a-whole.patch maple_tree-root-node-could-be-handled-by-p_slot-too.patch maple_tree-clear-request_count-for-new-allocated-one.patch maple_tree-total-is-not-changed-for-nomem_one-case.patch maple_tree-simplify-mas_push_node.patch maple_tree-calculate-new_end-when-needed.patch maple_tree-remove-sanity-check-from-mas_wr_slot_store.patch mm-vma-the-pgoff-is-correct-if-can_merge_right.patch maple_tree-print-empty-for-an-empty-tree-on-mt_dump.patch maple_tree-the-return-value-of-mas_root_expand-is-not-used.patch maple_tree-not-necessary-to-check-index-last-again.patch maple_tree-refine-mas_store_root-on-storing-null.patch maple_tree-add-a-test-checking-storing-null.patch