On Tue, 1 Mar 2022 00:11:12 +0800 xhao@linux.alibaba.com wrote:
On 2/28/22 4:13 PM, SeongJae Park wrote:
This commit makes DAMON sysfs interface supports the physical address space monitoring. Specifically, this commit adds support of the initial monitoring regions set feature by adding 'regions' directory under each target directory and makes context operations file to receive 'paddr' in addition to 'vaddr'.
As a result, the files hierarchy becomes as below:
/sys/kernel/mm/damon/admin │ kdamonds/nr_kdamonds │ │ 0/state,pid │ │ │ contexts/nr_contexts │ │ │ │ 0/operations │ │ │ │ │ monitoring_attrs/ │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us │ │ │ │ │ │ nr_regions/min,max │ │ │ │ │ targets/nr_targets │ │ │ │ │ │ 0/pid_target │ │ │ │ │ │ │ regions/nr_regions <- NEW DIRECTORY │ │ │ │ │ │ │ │ 0/start,end │ │ │ │ │ │ │ │ ... │ │ │ │ │ │ ... │ │ │ │ ... │ │ ...Signed-off-by: SeongJae Park sj@kernel.org
mm/damon/sysfs.c | 276 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 271 insertions(+), 5 deletions(-)
diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 9221c93db6cc..968a4ba8e81b 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -113,12 +113,220 @@ static struct kobj_type damon_sysfs_ul_range_ktype = { .default_groups = damon_sysfs_ul_range_groups, }; +/*
- init region directory
- */
+struct damon_sysfs_region {
- struct kobject kobj;
- unsigned long start;
- unsigned long end;
+};
+static struct damon_sysfs_region *damon_sysfs_region_alloc(
unsigned long start,unsigned long end)+{
- struct damon_sysfs_region *region = kmalloc(sizeof(*region),
GFP_KERNEL);- if (!region)
return NULL;- region->kobj = (struct kobject){};
- region->start = start;
- region->end = end;
- return region;
+}
The interface "start" and "end" have the same problems
[root@rt2k03395 0]# echo 100 > start [root@rt2k03395 0]# echo 10 > end [root@rt2k03395 0]# cat end 10 [root@rt2k03395 0]# cat start 100
As mentioned on the above answer[1], this is an intended behavior, so I don't think a fix is needed.
[1] https://lore.kernel.org/linux-mm/20220228162318.4046-1-sj@kernel.org/
Thanks, SJ
[...]
-- Best Regards! Xin Hao