From patchwork Fri Jul 26 18:42:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13743044 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E70763032A; Fri, 26 Jul 2024 18:42:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722019332; cv=none; b=i7326Dx9tAfDAG9yT4HUoL6h+GD09BszIkuCFfCc4HZWICBW+h8/7sXUnrgX/bjeP0xNxwMAcHvk90VdOHFp/Vu0Trsv8SCCqMhz1FXQohdvjXofs9UR50fqHyoY6BDDaj2T+TJsR4FJrfTjfrQQS3YJVR+HlkdDq+sNdXvWoew= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722019332; c=relaxed/simple; bh=zObUU4lAhpGpelL+rCoAJqPdcYFh3roDcp+/vRmSysE=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type; b=fJZBU07oW4yD56eNpms7IyiqZKWn12vmhO8QYwzfZvP1ttpPnVWNrvHpAy8aBlTqRzxq50t2gTzhdxVKngU8ftyFiMTREIR7OoC/kmkUIyT0pYPh+/n+UsNSA+ZNvHCxHtBgFhZnfyPR3Gi0chVO8aF5ArpZwLMDd9snvkM8Kt0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 04275C32782; Fri, 26 Jul 2024 18:42:10 +0000 (UTC) Date: Fri, 26 Jul 2024 14:42:08 -0400 From: Steven Rostedt To: LKML , Linux trace kernel Cc: Masami Hiramatsu , Mathieu Desnoyers Subject: [PATCH] tracing: Use refcount for trace_event_file reference counter Message-ID: <20240726144208.687cce24@rorschach.local.home> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Steven Rostedt Instead of using an atomic counter for the trace_event_file reference counter, use the refcount interface. It has various checks to make sure the reference counting is correct, and will warn if it detects an error (like refcount_inc() on '0'). Signed-off-by: Steven Rostedt (Google) Acked-by: Masami Hiramatsu (Google) --- include/linux/trace_events.h | 2 +- kernel/trace/trace_events.c | 8 ++++---- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 9df3e2973626..fed58e54f15e 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -680,7 +680,7 @@ struct trace_event_file { * caching and such. Which is mostly OK ;-) */ unsigned long flags; - atomic_t ref; /* ref count for opened files */ + refcount_t ref; /* ref count for opened files */ atomic_t sm_ref; /* soft-mode reference counter */ atomic_t tm_ref; /* trigger-mode reference counter */ }; diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 852643d957de..81ade9ddcbe5 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -992,18 +992,18 @@ static void remove_subsystem(struct trace_subsystem_dir *dir) void event_file_get(struct trace_event_file *file) { - atomic_inc(&file->ref); + refcount_inc(&file->ref); } void event_file_put(struct trace_event_file *file) { - if (WARN_ON_ONCE(!atomic_read(&file->ref))) { + if (WARN_ON_ONCE(!refcount_read(&file->ref))) { if (file->flags & EVENT_FILE_FL_FREED) kmem_cache_free(file_cachep, file); return; } - if (atomic_dec_and_test(&file->ref)) { + if (refcount_dec_and_test(&file->ref)) { /* Count should only go to zero when it is freed */ if (WARN_ON_ONCE(!(file->flags & EVENT_FILE_FL_FREED))) return; @@ -2999,7 +2999,7 @@ trace_create_new_event(struct trace_event_call *call, atomic_set(&file->tm_ref, 0); INIT_LIST_HEAD(&file->triggers); list_add(&file->list, &tr->events); - event_file_get(file); + refcount_set(&file->ref, 1); return file; }