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 742711FBEA8 for ; Mon, 7 Apr 2025 01:11:47 +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=1743988307; cv=none; b=PM9EYRrX5+OfnVny2WUkOxXjVBK7AaVz9MWxf2XTXXkk0ARQWBCMUIDFIQajIdprsNqfLQoECA63OzIEbzRoF1yAYoKmS1kR8ZGloop4VZvzNgnINA7J/ECuPUHFHWEWAOcDMkMp1PpPLyflz+I+Aq87ZXv5rnkVRdgr9AFnrBU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743988307; c=relaxed/simple; bh=Q4nN2FiN0EV4pXAUn5yUmBEDLP7L8p42KwKCH93DqiI=; h=Date:To:From:Subject:Message-Id; b=CVU4k4hhITDP8Ueg32sbDHZEQ0DQBvmHyl4nCtL0F9RzrarFIdtTVYn78/I/BqNgbd9hOcUC5ohNl1tV1+nmPrSiop0otm/D/40RSWCaMocC1oOTrOEwv8GRfqS3nT0Wh67tiFw0si82xsWyh6rhmYSlQ0wsyUbsBZMSgWWZhUM= 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=nmmHkuYv; 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="nmmHkuYv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C8194C4CEE3; Mon, 7 Apr 2025 01:11:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1743988306; bh=Q4nN2FiN0EV4pXAUn5yUmBEDLP7L8p42KwKCH93DqiI=; h=Date:To:From:Subject:From; b=nmmHkuYvG+FSDEavuKdZ1l54mrfdcgqNsLGVwxaQ1No943aL+9cOJsdO06kxTuip4 Bi/o3TWuItkJjTxQKS4yQKkIMIR0cX3FeMBqyAvW3ja65rzPiiQwsbGKg1Pfzs1cHl zFGks6/40fa5VsLezgryXTgIUw/MFk40NLYLw98k= Date: Sun, 06 Apr 2025 18:11:46 -0700 To: mm-commits@vger.kernel.org,tim.c.chen@linux.intel.com,kasong@tencent.com,bhe@redhat.com,shikemeng@huaweicloud.com,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-swap-rename-__swap__free-to-swap__put.patch added to mm-new branch Message-Id: <20250407011146.C8194C4CEE3@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm: swap: rename __swap_[entry/entries]_free[_locked] to swap_[entry/entries]_put[_locked] has been added to the -mm mm-new branch. Its filename is mm-swap-rename-__swap__free-to-swap__put.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-swap-rename-__swap__free-to-swap__put.patch This patch will later appear in the mm-new 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: Kemeng Shi Subject: mm: swap: rename __swap_[entry/entries]_free[_locked] to swap_[entry/entries]_put[_locked] Date: Wed, 26 Mar 2025 00:25:21 +0800 Patch series "Minor cleanups and improvements to swap freeing code", v4. This series contains some cleanups and improvements which are made during learning swapfile. Here is a summary of the changes: 1. Function naming improvments. - Use "put" instead of "free" to name functions which only do actual free when count drops to zero. - Use "entry" to name function only frees one swap slot. Use "entries" to name function could may free multi swap slots within one cluster. Use "_nr" suffix to name function which could free multi swap slots spanning cross multi clusters. 2. Eliminate the need to set swap slot to intermediate SWAP_HAS_CACHE value before do actual free by using swap_entry_range_free() 3. Add helpers swap_entries_put_map() and swap_entries_put_cache() as a general-purpose routine to free swap entries within a single cluster which will try batch-remove first and fallback to put eatch entry indvidually with cluster lock acquired/released only once. By using these helpers, we could remove repeated code, levarage batch-remove in more cases and aoivd to acquire/release cluster lock for each single swap entry. This patch (of 8): In __swap_entry_free[_locked] and __swap_entries_free, we decrease count first and only free swap entry if count drops to zero. This behavior is more akin to a put() operation rather than a free() operation. Therefore, rename these functions with "put" instead of "free". Additionally, add "_nr" suffix to swap_entries_put to indicate the input range may span swap clusters. Link: https://lkml.kernel.org/r/20250325162528.68385-1-shikemeng@huaweicloud.com Link: https://lkml.kernel.org/r/20250325162528.68385-2-shikemeng@huaweicloud.com Signed-off-by: Kemeng Shi Reviewed-by: Tim Chen Reviewed-by: Baoquan He Cc: Kairui Song Signed-off-by: Andrew Morton --- mm/swapfile.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) --- a/mm/swapfile.c~mm-swap-rename-__swap__free-to-swap__put +++ a/mm/swapfile.c @@ -1346,9 +1346,9 @@ out: return NULL; } -static unsigned char __swap_entry_free_locked(struct swap_info_struct *si, - unsigned long offset, - unsigned char usage) +static unsigned char swap_entry_put_locked(struct swap_info_struct *si, + unsigned long offset, + unsigned char usage) { unsigned char count; unsigned char has_cache; @@ -1452,15 +1452,15 @@ put_out: return NULL; } -static unsigned char __swap_entry_free(struct swap_info_struct *si, - swp_entry_t entry) +static unsigned char swap_entry_put(struct swap_info_struct *si, + swp_entry_t entry) { struct swap_cluster_info *ci; unsigned long offset = swp_offset(entry); unsigned char usage; ci = lock_cluster(si, offset); - usage = __swap_entry_free_locked(si, offset, 1); + usage = swap_entry_put_locked(si, offset, 1); if (!usage) swap_entry_range_free(si, ci, swp_entry(si->type, offset), 1); unlock_cluster(ci); @@ -1468,8 +1468,8 @@ static unsigned char __swap_entry_free(s return usage; } -static bool __swap_entries_free(struct swap_info_struct *si, - swp_entry_t entry, int nr) +static bool swap_entries_put_nr(struct swap_info_struct *si, + swp_entry_t entry, int nr) { unsigned long offset = swp_offset(entry); unsigned int type = swp_type(entry); @@ -1500,7 +1500,7 @@ static bool __swap_entries_free(struct s fallback: for (i = 0; i < nr; i++) { if (data_race(si->swap_map[offset + i])) { - count = __swap_entry_free(si, swp_entry(type, offset + i)); + count = swap_entry_put(si, swp_entry(type, offset + i)); if (count == SWAP_HAS_CACHE) has_cache = true; } else { @@ -1551,7 +1551,7 @@ static void cluster_swap_free_nr(struct ci = lock_cluster(si, offset); do { - if (!__swap_entry_free_locked(si, offset, usage)) + if (!swap_entry_put_locked(si, offset, usage)) swap_entry_range_free(si, ci, swp_entry(si->type, offset), 1); } while (++offset < end); unlock_cluster(ci); @@ -1598,7 +1598,7 @@ void put_swap_folio(struct folio *folio, swap_entry_range_free(si, ci, entry, size); else { for (int i = 0; i < size; i++, entry.val++) { - if (!__swap_entry_free_locked(si, offset + i, SWAP_HAS_CACHE)) + if (!swap_entry_put_locked(si, offset + i, SWAP_HAS_CACHE)) swap_entry_range_free(si, ci, entry, 1); } } @@ -1797,7 +1797,7 @@ void free_swap_and_cache_nr(swp_entry_t /* * First free all entries in the range. */ - any_only_cache = __swap_entries_free(si, entry, nr); + any_only_cache = swap_entries_put_nr(si, entry, nr); /* * Short-circuit the below loop if none of the entries had their @@ -1810,7 +1810,7 @@ void free_swap_and_cache_nr(swp_entry_t * Now go back over the range trying to reclaim the swap cache. This is * more efficient for large folios because we will only try to reclaim * the swap once per folio in the common case. If we do - * __swap_entry_free() and __try_to_reclaim_swap() in the same loop, the + * swap_entry_put() and __try_to_reclaim_swap() in the same loop, the * latter will get a reference and lock the folio for every individual * page but will only succeed once the swap slot for every subpage is * zero. @@ -3780,7 +3780,7 @@ outer: * into, carry if so, or else fail until a new continuation page is allocated; * when the original swap_map count is decremented from 0 with continuation, * borrow from the continuation and report whether it still holds more. - * Called while __swap_duplicate() or caller of __swap_entry_free_locked() + * Called while __swap_duplicate() or caller of swap_entry_put_locked() * holds cluster lock. */ static bool swap_count_continued(struct swap_info_struct *si, _ Patches currently in -mm which might be from shikemeng@huaweicloud.com are mm-swap-rename-__swap__free-to-swap__put.patch mm-swap-enable-swap_entry_range_free-to-drop-any-kind-of-last-ref.patch mm-swap-use-swap_entries_free-to-free-swap-entry-in-swap_entry_put_locked.patch mm-swap-use-swap_entries_free-drop-last-ref-count-in-swap_entries_put_nr.patch mm-swap-drop-last-swap_map_shmem-flag-in-batch-in-swap_entries_put_nr.patch mm-swap-free-each-cluster-individually-in-swap_entries_put_map_nr.patch mm-swap-factor-out-helper-to-drop-cache-of-entries-within-a-single-cluster.patch mm-swap-replace-cluster_swap_free_nr-with-swap_entries_put_.patch