From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Mathieu Desnoyers" , "Steven Rostedt (Red Hat)" Date: Sat, 07 Jun 2014 02:26:28 +0100 Message-ID: Subject: [PATCH 3.2 06/92] tracepoint: Do not waste memory on mods with no tracepoints In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.2.60-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: "Steven Rostedt (Red Hat)" commit 7dec935a3aa04412cba2cebe1524ae0d34a30c24 upstream. No reason to allocate tp_module structures for modules that have no tracepoints. This just wastes memory. Fixes: b75ef8b44b1c "Tracepoint: Dissociate from module mutex" Acked-by: Mathieu Desnoyers Signed-off-by: Steven Rostedt Signed-off-by: Ben Hutchings --- kernel/tracepoint.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -638,6 +638,9 @@ static int tracepoint_module_coming(stru struct tp_module *tp_mod, *iter; int ret = 0; + if (!mod->num_tracepoints) + return 0; + /* * We skip modules that taint the kernel, especially those with different * module headers (for forced load), to make sure we don't cause a crash. @@ -681,6 +684,9 @@ static int tracepoint_module_going(struc { struct tp_module *pos; + if (!mod->num_tracepoints) + return 0; + mutex_lock(&tracepoints_mutex); tracepoint_update_probe_range(mod->tracepoints_ptrs, mod->tracepoints_ptrs + mod->num_tracepoints);