Re: [PATCH 27/38] tools lib traceevent: Add mac80211 plugin

[Steven Rostedt <rostedt@goodmis.org>]

On Wed,  4 Dec 2013 17:06:51 -0300
Arnaldo Carvalho de Melo <acme@infradead.org> wrote:

> From: Jiri Olsa <jolsa@redhat.com>
> 
> Backporting mac80211 plugin.
> 
> Backported from Steven Rostedt's trace-cmd repo (HEAD 0f2c2fb):
> git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git
> 
> This plugin adds changed field resolving for
> mac80211:drv_bss_info_changed tracepoint event.
> 
> The diff of 'perf script' output generated by old and new code:
> (data was generated by 'perf record -e 'mac80211:drv_bss_info_changed' -a')
> 
>   --- script.mac80211.old
>   +++ script.mac80211.new
>   -        ifconfig  3711 [000]  1290.446492: mac80211:drv_bss_info_changed: phy0 vif:wlan0(2) changed:0x309f
>   +        ifconfig  3711 [000]  1290.446492: mac80211:drv_bss_info_changed: phy0 vif:wlan0(2)
>   +                                                                 assoc:0 aid:2 cts:0 shortpre:0 shortslot:0 dtimper:1
>   +                                                                 bcnint:102 assoc_cap:0x431 basic_rates:0xf enable_beacon:0
>   +                                                                 ht_operation_mode:0
> 
> Omitting the mac80211:drv_config tracepoint handling because the kernel
> tracepoint changed its prototype and the plugin handler is no longer
> working.

While doing my synchronization between trace-cmd and lib traceevent, I
noticed that the mac80211 driver is quite different.

Johannes, Jiri states that this plugin no longer works with the latest
kernels. Is that true?

-- Steve



> 
> Signed-off-by: Jiri Olsa <jolsa@redhat.com>
> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
> Cc: David Ahern <dsahern@gmail.com>
> Cc: Frederic Weisbecker <fweisbec@gmail.com>
> Cc: Ingo Molnar <mingo@elte.hu>
> Cc: Namhyung Kim <namhyung@kernel.org>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Link: http://lkml.kernel.org/r/1386076182-14484-17-git-send-email-jolsa@redhat.com
> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> ---
>  tools/lib/traceevent/Makefile          |  1 +
>  tools/lib/traceevent/plugin_mac80211.c | 95 ++++++++++++++++++++++++++++++++++
>  2 files changed, 96 insertions(+)
>  create mode 100644 tools/lib/traceevent/plugin_mac80211.c
> 
> diff --git a/tools/lib/traceevent/Makefile b/tools/lib/traceevent/Makefile
> index 226a8f9fb177..d0e0ca12aa10 100644
> --- a/tools/lib/traceevent/Makefile
> +++ b/tools/lib/traceevent/Makefile
> @@ -216,6 +216,7 @@ PLUGIN_OBJS  = plugin_jbd2.o
>  PLUGIN_OBJS += plugin_hrtimer.o
>  PLUGIN_OBJS += plugin_kmem.o
>  PLUGIN_OBJS += plugin_kvm.o
> +PLUGIN_OBJS += plugin_mac80211.o
>  
>  PLUGINS := $(PLUGIN_OBJS:.o=.so)
>  
> diff --git a/tools/lib/traceevent/plugin_mac80211.c b/tools/lib/traceevent/plugin_mac80211.c
> new file mode 100644
> index 000000000000..558a3b91c046
> --- /dev/null
> +++ b/tools/lib/traceevent/plugin_mac80211.c
> @@ -0,0 +1,95 @@
> +/*
> + * Copyright (C) 2009 Johannes Berg <johannes@sipsolutions.net>
> + *
> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation;
> + * version 2.1 of the License (not later!)
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with this program; if not,  see <http://www.gnu.org/licenses>
> + *
> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> + */
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +
> +#include "event-parse.h"
> +
> +#define INDENT 65
> +
> +static void print_string(struct trace_seq *s, struct event_format *event,
> +			 const char *name, const void *data)
> +{
> +	struct format_field *f = pevent_find_field(event, name);
> +	int offset;
> +	int length;
> +
> +	if (!f) {
> +		trace_seq_printf(s, "NOTFOUND:%s", name);
> +		return;
> +	}
> +
> +	offset = f->offset;
> +	length = f->size;
> +
> +	if (!strncmp(f->type, "__data_loc", 10)) {
> +		unsigned long long v;
> +		if (pevent_read_number_field(f, data, &v)) {
> +			trace_seq_printf(s, "invalid_data_loc");
> +			return;
> +		}
> +		offset = v & 0xffff;
> +		length = v >> 16;
> +	}
> +
> +	trace_seq_printf(s, "%.*s", length, (char *)data + offset);
> +}
> +
> +#define SF(fn)	pevent_print_num_field(s, fn ":%d", event, fn, record, 0)
> +#define SFX(fn)	pevent_print_num_field(s, fn ":%#x", event, fn, record, 0)
> +#define SP()	trace_seq_putc(s, ' ')
> +
> +static int drv_bss_info_changed(struct trace_seq *s,
> +				struct pevent_record *record,
> +				struct event_format *event, void *context)
> +{
> +	void *data = record->data;
> +
> +	print_string(s, event, "wiphy_name", data);
> +	trace_seq_printf(s, " vif:");
> +	print_string(s, event, "vif_name", data);
> +	pevent_print_num_field(s, "(%d)", event, "vif_type", record, 1);
> +
> +	trace_seq_printf(s, "\n%*s", INDENT, "");
> +	SF("assoc"); SP();
> +	SF("aid"); SP();
> +	SF("cts"); SP();
> +	SF("shortpre"); SP();
> +	SF("shortslot"); SP();
> +	SF("dtimper"); SP();
> +	trace_seq_printf(s, "\n%*s", INDENT, "");
> +	SF("bcnint"); SP();
> +	SFX("assoc_cap"); SP();
> +	SFX("basic_rates"); SP();
> +	SF("enable_beacon");
> +	trace_seq_printf(s, "\n%*s", INDENT, "");
> +	SF("ht_operation_mode");
> +
> +	return 0;
> +}
> +
> +int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
> +{
> +	pevent_register_event_handler(pevent, -1, "mac80211",
> +				      "drv_bss_info_changed",
> +				      drv_bss_info_changed, NULL);
> +	return 0;
> +}