[RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Lin Ming]

iwlwifi and iwlwifi_io tracepoint events are exported like below,

/sys/devices/pci0000:00/0000:00:1c.1/0000:03:00.0/net/wlan0/events/
|-- iwlwifi_dev_hcmd
|   |-- config
|   |-- type
|-- iwlwifi_dev_rx
|   |-- config
|   |-- type
....
....
|-- iwlwifi_dev_ioread32
|   |-- config
|   |-- type
|-- iwlwifi_dev_iowrite32
|   |-- config
|   |-- type
|-- iwlwifi_dev_iowrite8
|   |-- config
|   |-- type
---
 drivers/net/wireless/iwlwifi/iwl3945-base.c |   15 +++++++++++++++
 1 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/drivers/net/wireless/iwlwifi/iwl3945-base.c b/drivers/net/wireless/iwlwifi/iwl3945-base.c
index a27872d..cbcc2bb 100644
--- a/drivers/net/wireless/iwlwifi/iwl3945-base.c
+++ b/drivers/net/wireless/iwlwifi/iwl3945-base.c
@@ -41,6 +41,7 @@
 #include <linux/firmware.h>
 #include <linux/etherdevice.h>
 #include <linux/if_arp.h>
+#include <linux/perf_event.h>
 
 #include <net/ieee80211_radiotap.h>
 #include <net/mac80211.h>
@@ -3989,6 +3990,18 @@ static int iwl3945_setup_mac(struct iwl_priv *priv)
 	return 0;
 }
 
+static void iwl_sys_add_tp(struct kobject *kobj)
+{
+	struct kobject *events_kobj;
+
+	events_kobj = perf_sys_create_events_dir(kobj);
+	if (!events_kobj)
+		return;
+
+	perf_sys_add_tp_events(events_kobj, "iwlwifi");
+	perf_sys_add_tp_events(events_kobj, "iwlwifi_io");
+}
+
 static int iwl3945_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
 	int err = 0;
@@ -4148,6 +4161,8 @@ static int iwl3945_pci_probe(struct pci_dev *pdev, const struct pci_device_id *e
 		goto out_release_irq;
 	}
 
+	iwl_sys_add_tp(&pdev->dev.kobj);
+
 	iwl_set_rxon_channel(priv,
 			     &priv->bands[IEEE80211_BAND_2GHZ].channels[5]);
 	iwl3945_setup_deferred_work(priv);

Re: [RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Johannes Berg]

On Thu, 2010-07-22 at 19:13 +0800, Lin Ming wrote:
> iwlwifi and iwlwifi_io tracepoint events are exported like below,

>  drivers/net/wireless/iwlwifi/iwl3945-base.c |   15 +++++++++++++++
>  1 files changed, 15 insertions(+), 0 deletions(-)

err, how about iwlagn?

johannes

Re: [RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Steven Rostedt]

On Thu, 2010-07-22 at 13:20 +0200, Johannes Berg wrote:
> On Thu, 2010-07-22 at 19:13 +0800, Lin Ming wrote:
> > iwlwifi and iwlwifi_io tracepoint events are exported like below,
> 
> >  drivers/net/wireless/iwlwifi/iwl3945-base.c |   15 +++++++++++++++
> >  1 files changed, 15 insertions(+), 0 deletions(-)
> 
> err, how about iwlagn?


A lot of work went into making the include/trace/events/*.h be able to
automate the work. Now it seems that we are going to hand code a lot,
and a developer that adds a new system or such will now need to
understand the internals of perf to use it. That was what I strived to
avoid when creating the TRACE_EVENT() macros.

-- Steve

Re: [RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Ingo Molnar]

* Steven Rostedt <rostedt@goodmis.org> wrote:

> On Thu, 2010-07-22 at 13:20 +0200, Johannes Berg wrote:
> > On Thu, 2010-07-22 at 19:13 +0800, Lin Ming wrote:
> > > iwlwifi and iwlwifi_io tracepoint events are exported like below,
> > 
> > >  drivers/net/wireless/iwlwifi/iwl3945-base.c |   15 +++++++++++++++
> > >  1 files changed, 15 insertions(+), 0 deletions(-)
> > 
> > err, how about iwlagn?
> 
> A lot of work went into making the include/trace/events/*.h be able to 
> automate the work. Now it seems that we are going to hand code a lot, and a 
> developer that adds a new system or such will now need to understand the 
> internals of perf to use it. That was what I strived to avoid when creating 
> the TRACE_EVENT() macros.

Yeah - and the point of this submission is to allow the discussion of how to 
achieve these registrations.

Driver authors will want to have some control - for example the place where 
the events directory shows up in sysfs within the driver's directory structure 
- etc.

But we indeed want to automate it as much as possible.

Thanks,

	Ingo

Re: [RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Steven Rostedt]

On Thu, 2010-07-22 at 15:48 +0200, Ingo Molnar wrote:
> * Steven Rostedt <rostedt@goodmis.org> wrote:

> Yeah - and the point of this submission is to allow the discussion of how to 
> achieve these registrations.
> 
> Driver authors will want to have some control - for example the place where 
> the events directory shows up in sysfs within the driver's directory structure 
> - etc.
> 
> But we indeed want to automate it as much as possible.

Perhaps we can create a TRACE_EVENT_PATH() macro, that allows the
developer to specify the path that the event will be seen in sysfs?

-- Steve

Re: [RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Lin Ming]

On Thu, 2010-07-22 at 19:20 +0800, Johannes Berg wrote:
> On Thu, 2010-07-22 at 19:13 +0800, Lin Ming wrote:
> > iwlwifi and iwlwifi_io tracepoint events are exported like below,
> 
> >  drivers/net/wireless/iwlwifi/iwl3945-base.c |   15 +++++++++++++++
> >  1 files changed, 15 insertions(+), 0 deletions(-)
> 
> err, how about iwlagn?

Will add this.

> 
> johannes
> 

Re: [RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Dave Chinner]

On Thu, Jul 22, 2010 at 09:54:04AM -0400, Steven Rostedt wrote:
> On Thu, 2010-07-22 at 15:48 +0200, Ingo Molnar wrote:
> > * Steven Rostedt <rostedt@goodmis.org> wrote:
> 
> > Yeah - and the point of this submission is to allow the discussion of how to 
> > achieve these registrations.
> > 
> > Driver authors will want to have some control - for example the place where 
> > the events directory shows up in sysfs within the driver's directory structure 
> > - etc.
> > 
> > But we indeed want to automate it as much as possible.
> 
> Perhaps we can create a TRACE_EVENT_PATH() macro, that allows the
> developer to specify the path that the event will be seen in sysfs?

Perhaps you could build that into the event class definition as well
so each separate class in a subsystem can be placed in it's own
sub-directory?

That would make turning on and off specific classes trace points so
much simpler than it now, espcially for XFS where we now have > 250
tracepoints that are mostly defined by event classes already...

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

Re: [RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Steven Rostedt]

On Fri, 2010-07-23 at 11:37 +1000, Dave Chinner wrote:
> On Thu, Jul 22, 2010 at 09:54:04AM -0400, Steven Rostedt wrote:
> > On Thu, 2010-07-22 at 15:48 +0200, Ingo Molnar wrote:
> > > * Steven Rostedt <rostedt@goodmis.org> wrote:
> > 
> > > Yeah - and the point of this submission is to allow the discussion of how to 
> > > achieve these registrations.
> > > 
> > > Driver authors will want to have some control - for example the place where 
> > > the events directory shows up in sysfs within the driver's directory structure 
> > > - etc.
> > > 
> > > But we indeed want to automate it as much as possible.
> > 
> > Perhaps we can create a TRACE_EVENT_PATH() macro, that allows the
> > developer to specify the path that the event will be seen in sysfs?
> 
> Perhaps you could build that into the event class definition as well
> so each separate class in a subsystem can be placed in it's own
> sub-directory?
> 
> That would make turning on and off specific classes trace points so
> much simpler than it now, espcially for XFS where we now have > 250
> tracepoints that are mostly defined by event classes already...


I was working on creating a "TRACE_CATEGORY()" that allowed you to put
tracepoints into categories. Thus, these tracepoints will all still be
in the XFS system, but you can add hierarchical categories that let you
group and enable tracepoints in these groups.

But I stopped this work since it was more ftrace specific than perf, and
I need to figure out how to continue my work on ftrace and at the same
time merge it towards perf. This has been taking much longer than I have
expected. Perhaps I should just finish that work, and then see how we
can make perf work with it too?

-- Steve

Re: [RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Lin Ming]

On Fri, 2010-07-23 at 10:14 +0800, Steven Rostedt wrote:
> On Fri, 2010-07-23 at 11:37 +1000, Dave Chinner wrote:
> > On Thu, Jul 22, 2010 at 09:54:04AM -0400, Steven Rostedt wrote:
> > > On Thu, 2010-07-22 at 15:48 +0200, Ingo Molnar wrote:
> > > > * Steven Rostedt <rostedt@goodmis.org> wrote:
> > > 
> > > > Yeah - and the point of this submission is to allow the discussion of how to 
> > > > achieve these registrations.
> > > > 
> > > > Driver authors will want to have some control - for example the place where 
> > > > the events directory shows up in sysfs within the driver's directory structure 
> > > > - etc.
> > > > 
> > > > But we indeed want to automate it as much as possible.
> > > 
> > > Perhaps we can create a TRACE_EVENT_PATH() macro, that allows the
> > > developer to specify the path that the event will be seen in sysfs?
> > 
> > Perhaps you could build that into the event class definition as well
> > so each separate class in a subsystem can be placed in it's own
> > sub-directory?
> > 
> > That would make turning on and off specific classes trace points so
> > much simpler than it now, espcially for XFS where we now have > 250
> > tracepoints that are mostly defined by event classes already...
> 
> 
> I was working on creating a "TRACE_CATEGORY()" that allowed you to put
> tracepoints into categories. Thus, these tracepoints will all still be
> in the XFS system, but you can add hierarchical categories that let you
> group and enable tracepoints in these groups.
> 
> But I stopped this work since it was more ftrace specific than perf, and
> I need to figure out how to continue my work on ftrace and at the same
> time merge it towards perf. This has been taking much longer than I have
> expected. Perhaps I should just finish that work, and then see how we
> can make perf work with it too?

That's nice.

Does this "TRACE_CATEGORY()" can help to specify different event
attribute value?

/sys/devices/pci0000:00/0000:00:02.0/drm/card0/events
|-- i915_gem_object_bind
|   |-- config
|   |-- type
|   |-- filter  ==> filter for card0

/sys/devices/pci0000:00/0000:00:02.0/drm/card1/events
|-- i915_gem_object_bind
|   |-- config
|   |-- type
|   |-- filter  ==> filter for card1

In above example, the values of "config" and "type" are same.
But the values of "filter" are different.

Lin Ming

> 
> -- Steve
> 
> 

Re: [RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Steven Rostedt]

On Fri, 2010-07-23 at 10:45 +0800, Lin Ming wrote:
> On Fri, 2010-07-23 at 10:14 +0800, Steven Rostedt wrote:

> Does this "TRACE_CATEGORY()" can help to specify different event
> attribute value?
> 
> /sys/devices/pci0000:00/0000:00:02.0/drm/card0/events
> |-- i915_gem_object_bind
> |   |-- config
> |   |-- type
> |   |-- filter  ==> filter for card0
> 
> /sys/devices/pci0000:00/0000:00:02.0/drm/card1/events
> |-- i915_gem_object_bind
> |   |-- config
> |   |-- type
> |   |-- filter  ==> filter for card1
> 
> In above example, the values of "config" and "type" are same.
> But the values of "filter" are different.

No, it does not make a single event with different atts. It is just a
way to group events.

What you are showing is two events with the same name under two
different groups. But there still only exists one event (the place that
trace_i915_gem_object_bind() is located).

-- Steve

Re: [RFC][PATCH v1 06/15] perf: export tracepoint events via sysfs: iwlwifi and iwlwifi_io

[Dave Chinner]

On Thu, Jul 22, 2010 at 10:14:00PM -0400, Steven Rostedt wrote:
> On Fri, 2010-07-23 at 11:37 +1000, Dave Chinner wrote:
> > On Thu, Jul 22, 2010 at 09:54:04AM -0400, Steven Rostedt wrote:
> > > On Thu, 2010-07-22 at 15:48 +0200, Ingo Molnar wrote:
> > > > * Steven Rostedt <rostedt@goodmis.org> wrote:
> > > 
> > > > Yeah - and the point of this submission is to allow the discussion of how to 
> > > > achieve these registrations.
> > > > 
> > > > Driver authors will want to have some control - for example the place where 
> > > > the events directory shows up in sysfs within the driver's directory structure 
> > > > - etc.
> > > > 
> > > > But we indeed want to automate it as much as possible.
> > > 
> > > Perhaps we can create a TRACE_EVENT_PATH() macro, that allows the
> > > developer to specify the path that the event will be seen in sysfs?
> > 
> > Perhaps you could build that into the event class definition as well
> > so each separate class in a subsystem can be placed in it's own
> > sub-directory?
> > 
> > That would make turning on and off specific classes trace points so
> > much simpler than it now, espcially for XFS where we now have > 250
> > tracepoints that are mostly defined by event classes already...
> 
> I was working on creating a "TRACE_CATEGORY()" that allowed you to put
> tracepoints into categories. Thus, these tracepoints will all still be
> in the XFS system, but you can add hierarchical categories that let you
> group and enable tracepoints in these groups.

Yes, that's pretty much what I was thinking of.

> But I stopped this work since it was more ftrace specific than perf, and
> I need to figure out how to continue my work on ftrace and at the same
> time merge it towards perf. This has been taking much longer than I have
> expected. Perhaps I should just finish that work, and then see how we
> can make perf work with it too?

I'm not fussed - it's more of a wishlist item right now. If it's in
the pipeline, then I'm happy to wait until you've done all the hard
work for me. ;)

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com