linux-dev/mm/damon, branch linus/master

mm: damon: use HPAGE_PMD_SIZE

2022-05-19T21:08:55Z

Use HPAGE_PMD_SIZE instead of open coding. Link: https://lkml.kernel.org/r/20220517145120.118523-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Reviewed-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/reclaim: use resource_size function on resource object

2022-05-13T14:20:18Z

Fix the following coccicheck warnings: ./mm/damon/reclaim.c:241:30-33: WARNING: Suspicious code. resource_size is maybe missing with res. Link: https://lkml.kernel.org/r/20220507032512.129598-1-jiapeng.chong@linux.alibaba.com Signed-off-by: Jiapeng Chong Reported-by: Abaci Robot Reviewed-by: SeongJae Park Cc: "Boehme, Markus" Signed-off-by: Andrew Morton

mm/damon/reclaim: support online inputs update

2022-05-13T14:20:09Z

DAMON_RECLAIM reads the user input parameters only when it starts. To allow more efficient online tuning, this commit implements a new input parameter called 'commit_inputs'. Writing true to the parameter makes DAMON_RECLAIM reads the input parameters again. Link: https://lkml.kernel.org/r/20220429160606.127307-14-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/sysfs: support online inputs update

2022-05-13T14:20:09Z

Currently, DAMON sysfs interface doesn't provide a way for adjusting DAMON input parameters while it is turned on. Therefore, users who want to reconfigure DAMON need to stop DAMON and restart. This means all the monitoring results that accumulated so far, which could be useful, should be flushed. This would be inefficient for many cases. For an example, let's suppose a sysadmin was running a DAMON-based Operation Scheme to find memory regions not accessed for more than 5 mins and page out the regions. If it turns out the 5 mins threshold was too long and therefore the sysadmin wants to reduce it to 4 mins, the sysadmin should turn off DAMON, restart it, and wait for at least 4 more minutes so that DAMON can find the cold memory regions, even though DAMON was knowing there are regions that not accessed for 4 mins at the time of shutdown. This commit makes DAMON sysfs interface to support online DAMON input parameters updates by adding a new input keyword for the 'state' DAMON sysfs file, 'commit'. Writing the keyword to the 'state' file while the corresponding kdamond is running makes the kdamond to read the sysfs file values again and update the DAMON context. Link: https://lkml.kernel.org/r/20220429160606.127307-12-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/sysfs: update schemes stat in the kdamond context

2022-05-13T14:20:09Z

Only '->kdamond' and '->kdamond_stop' are protected by 'kdamond_lock' of 'struct damon_ctx'. All other DAMON context internal data items are recommended to be accessed in DAMON callbacks, or under some additional synchronizations. But, DAMON sysfs is accessing the schemes stat under 'kdamond_lock'. It makes no big issue as the read values are not used anywhere inside kernel, but would better to be fixed. This commit moves the reads to DAMON callback context, as supposed to be used for the purpose. Link: https://lkml.kernel.org/r/20220429160606.127307-11-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/sysfs: use enum for 'state' input handling

2022-05-13T14:20:08Z

DAMON sysfs 'state' file handling code is using string literals in both 'state_show()' and 'state_store()'. This makes the code error prone and inflexible for future extensions. To improve the situation, this commit defines possible input strings and 'enum' for identifying each input keyword only once, and refactors the code to reuse those. Link: https://lkml.kernel.org/r/20220429160606.127307-10-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/sysfs: reuse damon_set_regions() for regions setting

2022-05-13T14:20:08Z

'damon_set_regions()' is general enough so that it can also be used for only creating regions. This commit makes DAMON sysfs interface to reuse the function rather keeping two implementations for a same purpose. Link: https://lkml.kernel.org/r/20220429160606.127307-9-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/sysfs: move targets setup code to a separated function

2022-05-13T14:20:08Z

This commit separates DAMON sysfs interface's monitoring context targets setup code to a new function for better readability. Link: https://lkml.kernel.org/r/20220429160606.127307-8-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/sysfs: prohibit multiple physical address space monitoring targets

2022-05-13T14:20:08Z

Having multiple targets for physical address space monitoring makes no sense. This commit prohibits such a ridiculous DAMON context setup my making the DAMON context build function to check and return an error for the case. Link: https://lkml.kernel.org/r/20220429160606.127307-7-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/vaddr: remove damon_va_apply_three_regions()

2022-05-13T14:20:08Z

'damon_va_apply_three_regions()' is just a wrapper of its general version, 'damon_set_regions()'. This commit replaces the wrapper calls to directly call the general version. Link: https://lkml.kernel.org/r/20220429160606.127307-6-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton