Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753705AbbLJSxG (ORCPT ); Thu, 10 Dec 2015 13:53:06 -0500 Received: from mga14.intel.com ([192.55.52.115]:42872 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753374AbbLJSw7 (ORCPT ); Thu, 10 Dec 2015 13:52:59 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,409,1444719600"; d="scan'208";a="615998137" From: Tom Zanussi To: rostedt@goodmis.org Cc: 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 v13 17/29] tracing: Add hist trigger 'execname' modifier Date: Thu, 10 Dec 2015 12:50:59 -0600 Message-Id: <1b37ff453088298b2f32b761c504a89feb00f654.1449767187.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 Content-Length: 5992 Lines: 195 Allow users to have common_pid field values displayed as program names in the output by appending '.execname' to a common_pid field name: # echo hist:keys=common_pid.execname ... \ [ if filter] > event/trigger Signed-off-by: Tom Zanussi Tested-by: Masami Hiramatsu Reviewed-by: Namhyung Kim --- kernel/trace/trace.c | 3 +- kernel/trace/trace_events_hist.c | 100 ++++++++++++++++++++++++++++++++++++++- 2 files changed, 101 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index b1525b8..3c2beab 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3848,7 +3848,8 @@ 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 a23aa5e..c6f917f 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -84,6 +84,7 @@ 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 { @@ -233,6 +234,73 @@ 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; + } + + 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_each_hist_key_field(i, hist_data) { + 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 const 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); @@ -391,6 +459,9 @@ 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; @@ -608,11 +679,27 @@ static int create_tracing_map_fields(struct hist_trigger_data *hist_data) return 0; } +static bool need_trigger_ops(struct hist_trigger_data *hist_data) +{ + struct hist_field *key_field; + unsigned int i; + + for_each_hist_key_field(i, hist_data) { + key_field = hist_data->fields[i]; + + if (key_field->flags & HIST_FIELD_EXECNAME) + return true; + } + + return false; +} + static struct hist_trigger_data * create_hist_data(unsigned int map_bits, struct hist_trigger_attrs *attrs, struct trace_event_file *file) { + const struct tracing_map_ops *trigger_ops = NULL; struct hist_trigger_data *hist_data; int ret = 0; @@ -630,8 +717,11 @@ create_hist_data(unsigned int map_bits, if (ret) goto free; + if (need_trigger_ops(hist_data)) + trigger_ops = &hist_trigger_ops; + hist_data->map = tracing_map_create(map_bits, hist_data->key_size, - NULL, hist_data); + trigger_ops, hist_data); if (IS_ERR(hist_data->map)) { ret = PTR_ERR(hist_data->map); hist_data->map = NULL; @@ -742,6 +832,12 @@ 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)); @@ -861,6 +957,8 @@ 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/