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 6BA5630E82E for ; Sun, 8 Mar 2026 21:06:14 +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=1773003974; cv=none; b=h36uAaHnsjcaFRfPbpTciHKzfATh6my44MXemtxqaa1Fl07nAgDRGXMpurc4hs/qCT+KNLpGGEm93FU8Ty4GdSkOOhvCedix2k6ubEOmTlC8ebv52If4sjT9PFaW2GL6lCDIShzX5C2rTtqsT9SbXxcf2GYNKiOsun24jkD6fK0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773003974; c=relaxed/simple; bh=HKofCSvgfYM3EImwfc0eNDyCi7yPXOFCs1Z4+uiZn7A=; h=Date:To:From:Subject:Message-Id; b=J1txfEdGy2CcEBcJ0BhQ8+1OTf8BeyBHWXPwjYZjtGNPeTLHEsD57q9ITASKhwaXKZwG15/KNcyGMV1Lw59R6AGnMa8sLvk4Ow01AwbwP9C94xCeCVHgSCVDHqi98Ero2ne59hGF0tLTU5S4qljKoicWV1y9jbpWtPqS3k4+j24= 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=QgHhO4hU; 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="QgHhO4hU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EC95BC116C6; Sun, 8 Mar 2026 21:06:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1773003974; bh=HKofCSvgfYM3EImwfc0eNDyCi7yPXOFCs1Z4+uiZn7A=; h=Date:To:From:Subject:From; b=QgHhO4hUoC8Eju0KHNlfT8CJUcAO6BOUSomvzrqqVcU7hBYofpn+xgaBEIcwTyea1 73RNeiIm+hiRKxcaOl++6p2motGRKrvIaZVNC59XvB6AsU0psC0AhlAKpPKpteDoiY gnrUCc8X7Dmw8e0WBgqeEPticxyARSQf+a8d5hYM= Date: Sun, 08 Mar 2026 14:06:13 -0700 To: mm-commits@vger.kernel.org,ziy@nvidia.com,vbabka@kernel.org,usamaarif642@gmail.com,surenb@google.com,ryan.roberts@arm.com,rppt@kernel.org,npache@redhat.com,mhocko@suse.com,ljs@kernel.org,liam.howlett@oracle.com,lance.yang@linux.dev,jackmanb@google.com,hannes@cmpxchg.org,dev.jain@arm.com,david@kernel.org,baolin.wang@linux.alibaba.com,baohua@kernel.org,leitao@debian.org,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-huge_memory-refactor-enabled_store-with-change_enabled.patch added to mm-new branch Message-Id: <20260308210613.EC95BC116C6@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm: huge_memory: refactor enabled_store() with change_enabled() has been added to the -mm mm-new branch. Its filename is mm-huge_memory-refactor-enabled_store-with-change_enabled.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-huge_memory-refactor-enabled_store-with-change_enabled.patch This patch will later appear in the mm-new branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Note, mm-new is a provisional staging ground for work-in-progress patches, and acceptance into mm-new is a notification for others take notice and to finish up reviews. Please do not hesitate to respond to review feedback and post updated versions to replace or incrementally fixup patches in mm-new. The mm-new branch of mm.git is not included in linux-next If a few days of testing in mm-new is successful, the patch will me moved into mm.git's mm-unstable branch, which is included in linux-next 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: Breno Leitao Subject: mm: huge_memory: refactor enabled_store() with change_enabled() Date: Sat, 07 Mar 2026 08:08:07 -0800 Refactor enabled_store() to use a new change_enabled() helper. Introduce a separate enum global_enabled_mode and global_enabled_mode_strings[], mirroring the anon_enabled_mode pattern from the previous commit. A separate enum is necessary because the global THP setting does not support "inherit", only "always", "madvise", and "never". Reusing anon_enabled_mode would leave a NULL gap in the string array, causing sysfs_match_string() to stop early and fail to match entries after the gap. The helper uses the same loop pattern as change_anon_orders(), iterating over an array of flag bit positions and using test_and_set_bit()/test_and_clear_bit() to track whether the state actually changed. Link: https://lkml.kernel.org/r/20260307-thp_logs-v3-3-a45d2c8f3685@debian.org Signed-off-by: Breno Leitao Reviewed-by: Lorenzo Stoakes (Oracle) Cc: Baolin Wang Cc: Barry Song Cc: Brendan Jackman Cc: David Hildenbrand Cc: Dev Jain Cc: Johannes Weiner Cc: Lance Yang Cc: Liam Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Nico Pache Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Usama Arif Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton --- mm/huge_memory.c | 63 ++++++++++++++++++++++++++++++++++----------- 1 file changed, 48 insertions(+), 15 deletions(-) --- a/mm/huge_memory.c~mm-huge_memory-refactor-enabled_store-with-change_enabled +++ a/mm/huge_memory.c @@ -330,30 +330,63 @@ static const char * const anon_enabled_m [ANON_ENABLED_NEVER] = "never", }; +enum global_enabled_mode { + GLOBAL_ENABLED_ALWAYS, + GLOBAL_ENABLED_MADVISE, + GLOBAL_ENABLED_NEVER, +}; + +static const char * const global_enabled_mode_strings[] = { + [GLOBAL_ENABLED_ALWAYS] = "always", + [GLOBAL_ENABLED_MADVISE] = "madvise", + [GLOBAL_ENABLED_NEVER] = "never", +}; + +static bool change_enabled(enum global_enabled_mode mode) +{ + static const unsigned long thp_flags[] = { + TRANSPARENT_HUGEPAGE_FLAG, + TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, + }; + bool changed = false; + int i; + + for (i = 0; i < ARRAY_SIZE(thp_flags); i++) { + if (i == mode) + changed |= !test_and_set_bit(thp_flags[i], + &transparent_hugepage_flags); + else + changed |= test_and_clear_bit(thp_flags[i], + &transparent_hugepage_flags); + } + + return changed; +} + static ssize_t enabled_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { - ssize_t ret = count; + int mode; - if (sysfs_streq(buf, "always")) { - clear_bit(TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, &transparent_hugepage_flags); - set_bit(TRANSPARENT_HUGEPAGE_FLAG, &transparent_hugepage_flags); - } else if (sysfs_streq(buf, "madvise")) { - clear_bit(TRANSPARENT_HUGEPAGE_FLAG, &transparent_hugepage_flags); - set_bit(TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, &transparent_hugepage_flags); - } else if (sysfs_streq(buf, "never")) { - clear_bit(TRANSPARENT_HUGEPAGE_FLAG, &transparent_hugepage_flags); - clear_bit(TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, &transparent_hugepage_flags); - } else - ret = -EINVAL; + mode = sysfs_match_string(global_enabled_mode_strings, buf); + if (mode < 0) + return -EINVAL; - if (ret > 0) { + if (change_enabled(mode)) { int err = start_stop_khugepaged(); + if (err) - ret = err; + return err; + } else { + /* + * Recalculate watermarks even when the mode didn't + * change, as the previous code always called + * start_stop_khugepaged() which does this internally. + */ + set_recommended_min_free_kbytes(); } - return ret; + return count; } static struct kobj_attribute enabled_attr = __ATTR_RW(enabled); _ Patches currently in -mm which might be from leitao@debian.org are mm-khugepaged-export-set_recommended_min_free_kbytes.patch mm-huge_memory-refactor-anon_enabled_store-with-change_anon_orders.patch mm-huge_memory-refactor-enabled_store-with-change_enabled.patch mm-ratelimit-min_free_kbytes-adjustment-messages.patch