From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965739AbbJVSPj (ORCPT ); Thu, 22 Oct 2015 14:15:39 -0400 Received: from mga03.intel.com ([134.134.136.65]:61354 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965724AbbJVSPh (ORCPT ); Thu, 22 Oct 2015 14:15:37 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,183,1444719600"; d="scan'208";a="832799090" From: Tom Zanussi To: rostedt@goodmis.org Cc: daniel.wagner@bmw-carit.de, masami.hiramatsu.pt@hitachi.com, namhyung@kernel.org, josh@joshtriplett.org, andi@firstfloor.org, mathieu.desnoyers@efficios.com, peterz@infradead.org, linux-kernel@vger.kernel.org, Tom Zanussi Subject: [PATCH v11 17/28] tracing: Add hist trigger 'execname' modifier Date: Thu, 22 Oct 2015 13:14:21 -0500 Message-Id: <48db482555d15fbedf6e0492b4d7d78712e0f7a0.1445530672.git.tom.zanussi@linux.intel.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Allow users to have pid fields displayed as program names in the output by appending '.execname' to field names: # echo hist:keys=aaa.execname ... \ [ if filter] > event/trigger Signed-off-by: Tom Zanussi Tested-by: Masami Hiramatsu --- kernel/trace/trace.c | 3 +- kernel/trace/trace_events_hist.c | 86 +++++++++++++++++++++++++++++++++++++++- 2 files changed, 87 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 4f0968e..a143be0 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3822,7 +3822,8 @@ static const char readme_msg[] = "\t following modifiers to the field name, as applicable:\n\n" "\t .hex display a number as a hex value\n" "\t .sym display an address as a symbol\n" - "\t .sym-offset display an address as a symbol and offset\n\n" + "\t .sym-offset display an address as a symbol and offset\n" + "\t .execname display a common_pid as a program name\n\n" "\t The 'pause' parameter can be used to pause an existing hist\n" "\t trigger or to start a hist trigger but not log any events\n" "\t until told to do so. 'continue' can be used to start or\n" diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index e6e5c6e..656973a 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -75,6 +75,7 @@ enum hist_field_flags { HIST_FIELD_HEX = 8, HIST_FIELD_SYM = 16, HIST_FIELD_SYM_OFFSET = 32, + HIST_FIELD_EXECNAME = 64, }; struct hist_trigger_attrs { @@ -218,6 +219,78 @@ static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str) return ERR_PTR(ret); } +static inline void save_comm(char *comm, struct task_struct *task) +{ + if (!task->pid) { + strcpy(comm, ""); + return; + } + + if (WARN_ON_ONCE(task->pid < 0)) { + strcpy(comm, ""); + return; + } + + if (task->pid > PID_MAX_DEFAULT) { + strcpy(comm, "<...>"); + return; + } + + memcpy(comm, task->comm, TASK_COMM_LEN); +} + +static void hist_trigger_elt_free(struct tracing_map_elt *elt) +{ + kfree((char *)elt->private_data); +} + +static int hist_trigger_elt_alloc(struct tracing_map_elt *elt) +{ + struct hist_trigger_data *hist_data = elt->map->private_data; + struct hist_field *key_field; + unsigned int i; + + for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { + key_field = hist_data->fields[i]; + + if (key_field->flags & HIST_FIELD_EXECNAME) { + unsigned int size = TASK_COMM_LEN + 1; + + elt->private_data = kzalloc(size, GFP_KERNEL); + if (!elt->private_data) + return -ENOMEM; + break; + } + } + + return 0; +} + +static void hist_trigger_elt_copy(struct tracing_map_elt *to, + struct tracing_map_elt *from) +{ + char *comm_from = from->private_data; + char *comm_to = to->private_data; + + if (comm_from) + memcpy(comm_to, comm_from, TASK_COMM_LEN + 1); +} + +static void hist_trigger_elt_init(struct tracing_map_elt *elt) +{ + char *comm = elt->private_data; + + if (comm) + save_comm(comm, current); +} + +static struct tracing_map_ops hist_trigger_ops = { + .elt_alloc = hist_trigger_elt_alloc, + .elt_copy = hist_trigger_elt_copy, + .elt_free = hist_trigger_elt_free, + .elt_init = hist_trigger_elt_init, +}; + static void destroy_hist_field(struct hist_field *hist_field) { kfree(hist_field); @@ -376,6 +449,9 @@ static int create_key_field(struct hist_trigger_data *hist_data, flags |= HIST_FIELD_SYM; else if (!strcmp(field_str, "sym-offset")) flags |= HIST_FIELD_SYM_OFFSET; + else if (!strcmp(field_str, "execname") && + !strcmp(field_name, "common_pid")) + flags |= HIST_FIELD_EXECNAME; else { ret = -EINVAL; goto out; @@ -612,7 +688,7 @@ create_hist_data(unsigned int map_bits, goto free; hist_data->map = tracing_map_create(map_bits, hist_data->key_size, - NULL, hist_data); + &hist_trigger_ops, hist_data); if (IS_ERR(hist_data->map)) { ret = PTR_ERR(hist_data->map); hist_data->map = NULL; @@ -732,6 +808,12 @@ hist_trigger_entry_print(struct seq_file *m, sprint_symbol(str, uval); seq_printf(m, "%s: [%llx] %-55s", key_field->field->name, uval, str); + } else if (key_field->flags & HIST_FIELD_EXECNAME) { + char *comm = elt->private_data; + + uval = *(u64 *)(key + key_field->offset); + seq_printf(m, "%s: %-16s[%10llu]", + key_field->field->name, comm, uval); } else if (key_field->flags & HIST_FIELD_STRING) { seq_printf(m, "%s: %-50s", key_field->field->name, (char *)(key + key_field->offset)); @@ -851,6 +933,8 @@ static const char *get_hist_field_flags(struct hist_field *hist_field) flags_str = "sym"; else if (hist_field->flags & HIST_FIELD_SYM_OFFSET) flags_str = "sym-offset"; + else if (hist_field->flags & HIST_FIELD_EXECNAME) + flags_str = "execname"; return flags_str; } -- 1.9.3