Commit c274cd5c authored by Kaixu Xia's avatar Kaixu Xia Committed by Andrew Morton
Browse files

mm/damon/sysfs: simplify the judgement whether kdamonds are busy 

It is unnecessary to get the number of the running kdamond to judge
whether kdamonds are busy.  Here we can use the
damon_sysfs_kdamond_running() helper and return -EBUSY directly when
finding a running kdamond.  Meanwhile, merging with the judgement that a
kdamond has current sysfs command callback request to make the code more
clear.

Link: https://lkml.kernel.org/r/1662302166-13216-1-git-send-email-kaixuxia@tencent.com


Signed-off-by: default avatarKaixu Xia <kaixuxia@tencent.com>
Reviewed-by: default avatarSeongJae Park <sj@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 8eeda55f

mm/damon/sysfs.c

+7 −18
Original line number Diff line number Diff line
@@ -2657,23 +2657,18 @@ static void damon_sysfs_kdamonds_rm_dirs(struct damon_sysfs_kdamonds *kdamonds) 
	kdamonds->kdamonds_arr = NULL;

}



static int damon_sysfs_nr_running_ctxs(struct damon_sysfs_kdamond **kdamonds,

static bool damon_sysfs_kdamonds_busy(struct damon_sysfs_kdamond **kdamonds,

		int nr_kdamonds)

{

	int nr_running_ctxs = 0;

	int i;



	for (i = 0; i < nr_kdamonds; i++) {

		struct damon_ctx *ctx = kdamonds[i]->damon_ctx;



		if (!ctx)

			continue;

		mutex_lock(&ctx->kdamond_lock);

		if (ctx->kdamond)

			nr_running_ctxs++;

		mutex_unlock(&ctx->kdamond_lock);

		if (damon_sysfs_kdamond_running(kdamonds[i]) ||

		    damon_sysfs_cmd_request.kdamond == kdamonds[i])

			return true;

	}

	return nr_running_ctxs;



	return false;

}



static int damon_sysfs_kdamonds_add_dirs(struct damon_sysfs_kdamonds *kdamonds,
@@ -2682,15 +2677,9 @@ static int damon_sysfs_kdamonds_add_dirs(struct damon_sysfs_kdamonds *kdamonds, 
	struct damon_sysfs_kdamond **kdamonds_arr, *kdamond;

	int err, i;



	if (damon_sysfs_nr_running_ctxs(kdamonds->kdamonds_arr, kdamonds->nr))

	if (damon_sysfs_kdamonds_busy(kdamonds->kdamonds_arr, kdamonds->nr))

		return -EBUSY;



	for (i = 0; i < kdamonds->nr; i++) {

		if (damon_sysfs_cmd_request.kdamond ==

				kdamonds->kdamonds_arr[i])

			return -EBUSY;

	}



	damon_sysfs_kdamonds_rm_dirs(kdamonds);

	if (!nr_kdamonds)

		return 0;