From nobody Wed Apr 8 04:46:31 2026 Received: from stravinsky.debian.org (stravinsky.debian.org [82.195.75.108]) (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 CEDEE3B2FCF for ; Tue, 10 Mar 2026 17:58:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=82.195.75.108 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773165509; cv=none; b=ryzTmMtnldctHSVCer/ZmOP03Ck7LHJQsWU0lxeCdrWHS5YMwQ+gC3fzZi51f4sF+2oW0/FPcFzJj5vj6w+hlPLczKqKe/Qn3acDcBEnyMSoMYq2OmKBu0UTqwxrX8z2ybJFpguNqSmUlDC/ucMUfBwQjPADxW9y3h7Qs95yt3o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773165509; c=relaxed/simple; bh=54S5CSIQXghjorDUhiNPNrDbTvMVQVjcEp0k9HQNOlw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=QJK+3vWDJ2erw9GFsJTuVgC944hZPyzc+PNXLRBzus4QHrnoUlp3q2jEaVfVNlE8jHIdaQv1DI6WomOlOrbHskvo8nyWCl0nWnotqBMmZe0JLCtvTcfdsXBKQ3EIXHLgNlLYQ8XWNFgUiKywqm2A4VvEdWC8gUftTkBALB4jEAk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=debian.org; spf=none smtp.mailfrom=debian.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b=K/jkfCPZ; arc=none smtp.client-ip=82.195.75.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=debian.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=debian.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b="K/jkfCPZ" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org; s=smtpauto.stravinsky; h=X-Debian-User:Cc:To:In-Reply-To:References: Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description; bh=Adafq0Gul2Zbse7gcvbdTyGVQp6wWAvKLR/NocJiy5c=; b=K/jkfCPZkHSQw+rmes0kZY6pXk XzYISbxzCJfLWh7pwm5wu7MEjrPCRkxRHpg1CSsJDQuefRDXam3sTwTJnFg3/YeHEv/9+xON0YN6H 8iB8fJtrFdqXg8wjkUTykHi6wtUjPCJzuSJNMeWxbgHxdr9SyKpGGZVdEnAAc7z2kTasy/vKFCjK1 uu1LNuTgs8Pw9yyoCXNjAthjPELCR27LQxT/A2PrJeXZT8Pzl2d60bitIiUEGyVInU37a+mEGpefw yz1So2plRYKYIX9JZHiQD+q0kZoNfXEc7V5MYl6OHGFNqwuUYhimkKOQ7zChigYWXf7u9X90oBQdc KHWsshxQ==; Received: from authenticated user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94.2) (envelope-from ) id 1w01LQ-003AZs-5p; Tue, 10 Mar 2026 17:58:12 +0000 From: Breno Leitao Date: Tue, 10 Mar 2026 10:57:09 -0700 Subject: [PATCH v5 3/4] mm: huge_memory: refactor enabled_store() with change_enabled() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260310-thp_logs-v5-3-686099175bf6@debian.org> References: <20260310-thp_logs-v5-0-686099175bf6@debian.org> In-Reply-To: <20260310-thp_logs-v5-0-686099175bf6@debian.org> To: Andrew Morton , David Hildenbrand , Lorenzo Stoakes , Zi Yan , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Mike Rapoport Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, usamaarif642@gmail.com, kas@kernel.org, kernel-team@meta.com, Breno Leitao , "Lorenzo Stoakes (Oracle)" X-Mailer: b4 0.15-dev-363b9 X-Developer-Signature: v=1; a=openpgp-sha256; l=3491; i=leitao@debian.org; h=from:subject:message-id; bh=54S5CSIQXghjorDUhiNPNrDbTvMVQVjcEp0k9HQNOlw=; b=owEBbQKS/ZANAwAIATWjk5/8eHdtAcsmYgBpsFubiT+Qbo4tOy2dfd3/EQB8Y5nRx/2MGduNa 1bgNh6kaO+JAjMEAAEIAB0WIQSshTmm6PRnAspKQ5s1o5Of/Hh3bQUCabBbmwAKCRA1o5Of/Hh3 bUjOD/9B/LZbAZOE2fDBsLYWZL1iT/JfGNb0nfLhkmiSxOMAwEAF3rT1cVFeGwFqQuDCs9J3u0h +roIyfnWayPnjsn3A0RAnA7QF6IXXdulHteRH+F2iw7XeNd1snH4UqB87wJ8xPuJ4DZJ1pJwsw7 O5EX+bkrLJs9w58Q5+oautp03Bt+/9ZOWRQLCtxkDWSGP/LBWCNP47LZMhlqMNscH0JgFqmBdqM SDm7Fr9gdy7/2ec4UADAqxhEFozM/dp5EtavS4fBi1/Na94NCXG2j+C9vwHhUvvdbDZe11XdnFS wN8/uDhIzUGnGGEfVHHylRTaViU/OagZO1bGSnK3Igks5QWi9FfyxgH49MXR6WqoNJwp1tBUS9V u6qYEhtVJeqtr05uzC7zDWX/cMdBkFMZh6SpRKC/68P087GQGzY9L9xUGjz77cKbyOGbLkO+vgE vIpcpPKdwTZ+VTQTQPuCTIXHzXm/do2Qi516dVINL2XRewDF9OGdyacIUUvWDs50sToZxWx6RPq 19sLGHkyowDEwE8+4fpOTnDCNXo1D35OUflNkiar2NgZbxmuK7+Sl1Qo5AbVy7rC8OrQDHxr3/8 f+pp36PSSqAwYSyTV3CFiqHCwY6u9LGgZQwiH2gzslgiqmFBSLVfQPyRjXpwQN+Yxl9ciEwRWGG lGj0eoXX0Daghbg== X-Developer-Key: i=leitao@debian.org; a=openpgp; fpr=AC8539A6E8F46702CA4A439B35A3939FFC78776D X-Debian-User: leitao 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 set_anon_enabled_mode(), 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. Signed-off-by: Breno Leitao Reviewed-by: Lorenzo Stoakes (Oracle) Reviewed-by: Baolin Wang Reviewed-by: Wei Yang Reviewed-by: Zi Yan --- mm/huge_memory.c | 63 ++++++++++++++++++++++++++++++++++++++++++----------= ---- 1 file changed, 48 insertions(+), 15 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index e19dda5aaf195..cc98a3b8bc247 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -330,30 +330,63 @@ static const char * const anon_enabled_mode_strings[]= =3D { [ANON_ENABLED_NEVER] =3D "never", }; =20 +enum global_enabled_mode { + GLOBAL_ENABLED_ALWAYS =3D 0, + GLOBAL_ENABLED_MADVISE =3D 1, + GLOBAL_ENABLED_NEVER =3D 2, +}; + +static const char * const global_enabled_mode_strings[] =3D { + [GLOBAL_ENABLED_ALWAYS] =3D "always", + [GLOBAL_ENABLED_MADVISE] =3D "madvise", + [GLOBAL_ENABLED_NEVER] =3D "never", +}; + +static bool set_global_enabled_mode(enum global_enabled_mode mode) +{ + static const unsigned long thp_flags[] =3D { + TRANSPARENT_HUGEPAGE_FLAG, + TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, + }; + enum global_enabled_mode m; + bool changed =3D false; + + for (m =3D 0; m < ARRAY_SIZE(thp_flags); m++) { + if (m =3D=3D mode) + changed |=3D !__test_and_set_bit(thp_flags[m], + &transparent_hugepage_flags); + else + changed |=3D __test_and_clear_bit(thp_flags[m], + &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 =3D count; + int mode; =20 - if (sysfs_streq(buf, "always")) { - clear_bit(TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, &transparent_hugepage_flag= s); - 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_flag= s); - } else - ret =3D -EINVAL; + mode =3D sysfs_match_string(global_enabled_mode_strings, buf); + if (mode < 0) + return -EINVAL; =20 - if (ret > 0) { + if (set_global_enabled_mode(mode)) { int err =3D start_stop_khugepaged(); + if (err) - ret =3D 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; } =20 static struct kobj_attribute enabled_attr =3D __ATTR_RW(enabled); --=20 2.52.0