Re: [PATCH 2/3] mm/damon/sysfs: support fixed virtual address ranges monitoring

[Rongwei Wang]

Hi, SeongJae

I had read and tested your patchset these days. It works.
It seems that these patches only fix the issue about init_regions in 
DAMON-sysfs, but not fix in DAMON-dbgfs? maybe I missing something.

If so, do you have any plan to fix this bug in dbgfs? Actually, what I 
want to say is that I ready a patch for solving the init_regions related 
bug in dbgfs these days. I not sure if you're interested in it.

Best Regards,
Rongwei

On 4/27/22 7:17 AM, sj@xxxxxxxxxx wrote:
> From: SeongJae Park <sj@xxxxxxxxxx>
>
> This commit makes DAMON sysfs interface to support the fixed virtual
> address ranges monitoring.  After this commit, writing 'fvaddr' to the
> 'operations' DAMON sysfs file makes DAMON uses the monitoring operations
> set for fixed virtual address ranges, so that users can monitor accesses
> to only interested virtual address ranges.
>
> Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
> ---
>   mm/damon/sysfs.c | 8 +++-----
>   1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
> index 719a286d378f..767ab8c33e4d 100644
> --- a/mm/damon/sysfs.c
> +++ b/mm/damon/sysfs.c
> @@ -1694,7 +1694,7 @@ static struct kobj_type damon_sysfs_attrs_ktype = {
>   /* This should match with enum damon_ops_id */
>   static const char * const damon_sysfs_ops_strs[] = {
>   	"vaddr",
> -	"unsupported",	/* fvaddr is not supported by sysfs yet */
> +	"fvaddr",
>   	"paddr",
>   };
>   
> @@ -1844,9 +1844,6 @@ static ssize_t operations_store(struct kobject *kobj,
>   
>   	for (id = 0; id < NR_DAMON_OPS; id++) {
>   		if (sysfs_streq(buf, damon_sysfs_ops_strs[id])) {
> -			/* fvaddr is not supported by sysfs yet */
> -			if (id == DAMON_OPS_FVADDR)
> -				return -EINVAL;
>   			context->ops_id = id;
>   			return count;
>   		}
> @@ -2136,7 +2133,8 @@ static int damon_sysfs_set_targets(struct damon_ctx *ctx,
>   			damon_sysfs_destroy_targets(ctx);
>   			return -ENOMEM;
>   		}
> -		if (ctx->ops.id == DAMON_OPS_VADDR) {
> +		if (ctx->ops.id == DAMON_OPS_VADDR ||
> +				ctx->ops.id == DAMON_OPS_FVADDR) {
>   			t->pid = find_get_pid(sys_target->pid);
>   			if (!t->pid) {
>   				damon_sysfs_destroy_targets(ctx);