From c274cd5c9bf5ded4b3f2a4e99f76223c8f006051 Mon Sep 17 00:00:00 2001 From: Kaixu Xia Date: Sun, 4 Sep 2022 22:36:06 +0800 Subject: [PATCH] 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: Kaixu Xia Reviewed-by: SeongJae Park Signed-off-by: Andrew Morton --- mm/damon/sysfs.c | 25 +++++++------------------ 1 file changed, 7 insertions(+), 18 deletions(-) diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 7488e27..fe6c6870c 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -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; -- 2.7.4