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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, usamaarif642@gmail.com, kas@kernel.org, kernel-team@meta.com References: <20260305-thp_logs-v2-0-96b3ad795894@debian.org> <20260305-thp_logs-v2-2-96b3ad795894@debian.org> From: Baolin Wang In-Reply-To: <20260305-thp_logs-v2-2-96b3ad795894@debian.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 03BDF1A0002 X-Stat-Signature: 9gh3z68nee48n3ftkyp8bfiqp5d8h3zg X-Rspam-User: X-HE-Tag: 1772777279-521617 X-HE-Meta: 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 0jBs0/LG 97hBRz2G6hXA7QCmpNt7RgEjTkfQX0fBT6J6D4cRGTaua/BzQW6FquBU4pF6EEHzvreajrOfGfA5FeT6wu7upRsniwFb0omTRKVIHaqHtvauFysHcNFCwRnIhNsZBgdJjXkLPATP9Kcq7cn6gOYjyBzjH3SHrt1OjOmA4TagVy7dnsTGI5KlOFUQ0U1dhoclTF2vAmm96H7+/2EfxwNPWtiQP7Or/dJ60MIBazCZIYJtw9aOguOkLgnq/J1HaTPDIOzTea1TbXldnXIlYhas2ILOwWPiHVJ2w89aOtDwCopAKiMhqiWymK1ML8SibuCzrcbgBACsJYyBcj79K1kGhsDolti0qlbJLSbpM+uwrbNezWg98SvXBu8QcYN5xeXzl8yrZUkp2vFLZH9lfaoGZXSY15qKnbxbQVGU3 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 3/5/26 10:04 PM, Breno Leitao wrote: > Consolidate the repeated spin_lock/set_bit/clear_bit pattern in > anon_enabled_store() into a new change_anon_orders() helper that > loops over an orders[] array, setting the bit for the selected mode > and clearing the others. > > Introduce enum enabled_mode and enabled_mode_strings[] to be shared > with enabled_store() in a subsequent patch. > > Use sysfs_match_string() with the enabled_mode_strings[] table to > replace the if/else chain of sysfs_streq() calls. > > The helper uses test_and_set_bit()/test_and_clear_bit() to track > whether the state actually changed, so start_stop_khugepaged() is > only called when needed. When the mode is unchanged, > set_recommended_min_free_kbytes() is called directly to preserve > the watermark recalculation behavior of the original code. > > Signed-off-by: Breno Leitao > --- > mm/huge_memory.c | 84 +++++++++++++++++++++++++++++++++++--------------------- > 1 file changed, 52 insertions(+), 32 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 8e2746ea74adf..19619213f54d1 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -316,6 +316,20 @@ static ssize_t enabled_show(struct kobject *kobj, > return sysfs_emit(buf, "%s\n", output); > } > > +enum enabled_mode { > + ENABLED_ALWAYS, > + ENABLED_MADVISE, > + ENABLED_INHERIT, > + ENABLED_NEVER, > +}; > + > +static const char * const enabled_mode_strings[] = { > + [ENABLED_ALWAYS] = "always", > + [ENABLED_MADVISE] = "madvise", > + [ENABLED_INHERIT] = "inherit", > + [ENABLED_NEVER] = "never", > +}; > + > static ssize_t enabled_store(struct kobject *kobj, > struct kobj_attribute *attr, > const char *buf, size_t count) > @@ -515,48 +529,54 @@ static ssize_t anon_enabled_show(struct kobject *kobj, > return sysfs_emit(buf, "%s\n", output); > } > > +static bool change_anon_orders(int order, enum enabled_mode mode) > +{ > + static unsigned long *orders[] = { > + &huge_anon_orders_always, > + &huge_anon_orders_madvise, > + &huge_anon_orders_inherit, > + }; > + bool changed = false; > + int i; > + > + spin_lock(&huge_anon_orders_lock); > + for (i = 0; i < ARRAY_SIZE(orders); i++) { > + if (i == mode) > + changed |= !test_and_set_bit(order, orders[i]); > + else > + changed |= test_and_clear_bit(order, orders[i]); > + } > + spin_unlock(&huge_anon_orders_lock); > + > + return changed; > +} > + > static ssize_t anon_enabled_store(struct kobject *kobj, > struct kobj_attribute *attr, > const char *buf, size_t count) > { > int order = to_thpsize(kobj)->order; > - ssize_t ret = count; > + int mode; > > - if (sysfs_streq(buf, "always")) { > - spin_lock(&huge_anon_orders_lock); > - clear_bit(order, &huge_anon_orders_inherit); > - clear_bit(order, &huge_anon_orders_madvise); > - set_bit(order, &huge_anon_orders_always); > - spin_unlock(&huge_anon_orders_lock); > - } else if (sysfs_streq(buf, "inherit")) { > - spin_lock(&huge_anon_orders_lock); > - clear_bit(order, &huge_anon_orders_always); > - clear_bit(order, &huge_anon_orders_madvise); > - set_bit(order, &huge_anon_orders_inherit); > - spin_unlock(&huge_anon_orders_lock); > - } else if (sysfs_streq(buf, "madvise")) { > - spin_lock(&huge_anon_orders_lock); > - clear_bit(order, &huge_anon_orders_always); > - clear_bit(order, &huge_anon_orders_inherit); > - set_bit(order, &huge_anon_orders_madvise); > - spin_unlock(&huge_anon_orders_lock); > - } else if (sysfs_streq(buf, "never")) { > - spin_lock(&huge_anon_orders_lock); > - clear_bit(order, &huge_anon_orders_always); > - clear_bit(order, &huge_anon_orders_inherit); > - clear_bit(order, &huge_anon_orders_madvise); > - spin_unlock(&huge_anon_orders_lock); > - } else > - ret = -EINVAL; > + mode = sysfs_match_string(enabled_mode_strings, buf); > + if (mode < 0) > + return -EINVAL; > > - if (ret > 0) { > - int err; > + if (change_anon_orders(order, mode)) { > + int err = start_stop_khugepaged(); Thanks for the cleanup, and the code looks better. > > - 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(); However, this won’t fix your issue. You will still get lots of warning messages even if no hugepage options are changed.