From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 8086A39021C for ; Fri, 21 Aug 2026 22:43:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787352226; cv=none; b=k4FuP8+yYoFOH1JHsMZq+uwkFnv8QQbuQ42F54fDFn7jURrU6+udAeD4PvmRUSo9imc3yzXKvFtjx0X3OeqTw0eSBfUOK2M/s9QLqCod51b9L9kKlzMoQSFEzbxlKRQmQT60QeVqvTWrs40Q4XQnTYnlkcM/WfGhZ3cNcM0pU80= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787352226; c=relaxed/simple; bh=9elKwhtE6VazgkBuSSQaKpriWGY0/zkjP48HGZeelq0=; h=Date:To:From:Subject:Message-Id; b=hqg5HC6VuEMvvoZsoyOPUOVZnejcVBteQJLFcGZ6A9K6baOTqlLCESlWjKW91C7LO0G1oyLROWFyCyccjDhFQte3XKX2LuvbCfnuIM4MaITgkXF+QzjQieufc8Cfv3vJtZ4oaslp64ZijODwGitLMS/ES8IScSqoRb0OSn9f3MM= 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=Xg5XFGyc; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="Xg5XFGyc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4DCE51F000E9; Fri, 21 Aug 2026 22:43:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1787352225; bh=UTNCbly82S3Jq3qr4I8TNrnKg13DnJhYSfXjVOvb8Bs=; h=Date:To:From:Subject; b=Xg5XFGycZJlA4QWj66svlWWF2RhBWa9e+wBONYJyxvkbmrDBS8zfdGj/SUsCEyRkY zyACXmbEpdsW5PZRxg7rNwwNSNkigxPs1F7OnaOv9jvneTVVQ4PXKMEonau0fX5dFW mMqt0SA2ajvLG6FcqvfoSlbaTDBmVtBxwlbXO1kU= Date: Fri, 21 Aug 2026 15:43:44 -0700 To: mm-commits@vger.kernel.org,liam@infradead.org,akpm@linux-foundation.org From: Andrew Morton Subject: + maple_tree-clarify-comments-on-mas_nomem.patch added to mm-unstable branch Message-Id: <20260821224345.4DCE51F000E9@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: clarify comments on mas_nomem() has been added to the -mm mm-unstable branch. Its filename is maple_tree-clarify-comments-on-mas_nomem.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/maple_tree-clarify-comments-on-mas_nomem.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 various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: "Liam R. Howlett (Oracle)" Subject: maple_tree: clarify comments on mas_nomem() Date: Fri, 21 Aug 2026 15:26:15 -0400 When an allocation completely fails, the return is false. If the allocation succeeds or partially succeeds, return true to indicate a retry of the operation. Note that since the lock may have been dropped, the operation is retried from the start - including potentially allocating more memory. Link: https://lore.kernel.org/20260821192627.4085470-8-liam@infradead.org Signed-off-by: Liam R. Howlett (Oracle) Cc: Boqun Feng Cc: Breno Leitao Cc: Chris Mason Cc: Chuck Lever Cc: Ingo Molnar Cc: Jason Gunthorpe Cc: Joe Perches Cc: Peter Zijlstra Cc: Rik van Riel Cc: Waiman Long Cc: Will Deacon Signed-off-by: Andrew Morton --- lib/maple_tree.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/lib/maple_tree.c~maple_tree-clarify-comments-on-mas_nomem +++ a/lib/maple_tree.c @@ -5677,10 +5677,11 @@ EXPORT_SYMBOL_GPL(mas_erase); /** * mas_nomem() - Check if there was an error allocating and do the allocation - * if necessary If there are allocations, then free them. + * if necessary. + * * @mas: The maple state * @gfp: The GFP_FLAGS to use for allocations - * Return: true on allocation, false otherwise. + * Return: False on no memory. True otherwise (partial success as well) */ bool mas_nomem(struct ma_state *mas, gfp_t gfp) __must_hold(mas->tree->ma_lock) @@ -5696,6 +5697,10 @@ bool mas_nomem(struct ma_state *mas, gfp mas_alloc_nodes(mas, gfp); } + /* + * Return false on zero forward progress. Partial allocations are kept + * so the retry path will attempt to get the rest. + */ if (!mas->sheaf && !mas->alloc) return false; _ Patches currently in -mm which might be from liam@infradead.org are maple_tree-add-rcu-locking-check-when-lockdep-is-enabled.patch locking-lockdep-add-sequence-counter-to-held_lock.patch maple_tree-add-write-lock-checking-with-lockdep-sequence-numbers.patch maple_tree-documentation-fix.patch maple_tree-drop-dead-code-from-mas_extend_spanning_null.patch maple_tree-drop-maple_alloc_slots.patch maple_tree-clarify-comments-on-mas_nomem.patch maple_tree-use-prefetched-value-in-mas_wr_store_type.patch maple_tree-optimise-mas_wr_node_store-when-not-in-rcu-mode.patch maple_tree-micro-optimisation-of-mas_wr_store_type.patch maple_tree-add-bulk-parent-set-helper.patch maple_tree-catch-race-in-mas_alloc_cyclic.patch maple_tree-document-that-erase-may-use-gfp_kernel-for-allocations.patch maple_tree-avoid-mas_erase-and-mtree_erase-failures.patch maple_tree-document-erase-and-allocations-better.patch maple_tree-change-two-gfp-flags-in-tests.patch maple_tree-fix-argument-name-in-header.patch maple_tree-avoid-extra-gap-calculation.patch maple_tree-add-helper-mas_make_walkable.patch