From: Changbin Du <changbin.du@xxxxxxxxx> Subject: mm/damon: needn't hold kdamond_lock to print pid of kdamond Just get the pid by 'current->pid'. Meanwhile, to be symmetrical make the 'starts' and 'finishes' logs both use debug level. Link: https://lkml.kernel.org/r/20210927232432.17750-1-changbin.du@xxxxxxxxx Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx> Reviewed-by: SeongJae Park <sj@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/damon/core.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) --- a/mm/damon/core.c~mm-damon-neednt-hold-kdamond_lock-to-print-pid-of-kdamond +++ a/mm/damon/core.c @@ -652,9 +652,7 @@ static int kdamond_fn(void *data) unsigned int max_nr_accesses = 0; unsigned long sz_limit = 0; - mutex_lock(&ctx->kdamond_lock); - pr_debug("kdamond (%d) starts\n", ctx->kdamond->pid); - mutex_unlock(&ctx->kdamond_lock); + pr_debug("kdamond (%d) starts\n", current->pid); if (ctx->primitive.init) ctx->primitive.init(ctx); @@ -705,7 +703,7 @@ static int kdamond_fn(void *data) if (ctx->primitive.cleanup) ctx->primitive.cleanup(ctx); - pr_debug("kdamond (%d) finishes\n", ctx->kdamond->pid); + pr_debug("kdamond (%d) finishes\n", current->pid); mutex_lock(&ctx->kdamond_lock); ctx->kdamond = NULL; mutex_unlock(&ctx->kdamond_lock); _