Re: [PATCH] drm/xe/pm: Add trace for pm functions

[Matthew Brost <matthew.brost@intel.com>]

On Wed, Jul 17, 2024 at 01:29:08PM +0200, Nirmoy Das wrote:
> Add trace for xe pm function for better debuggability.
> 
> Cc: Matthew Brost <matthew.brost@intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
> ---
> Example Output: 
>           <idle>-0       [004] d.h2.  3821.138392: xe_pm_runtime_put: dev=0000:00:02.0 caller_function=xe_guc_ct_fast_path+0x2e4/0x430 [xe]
>    kworker/u32:0-53314   [001] .....  3821.138411: xe_pm_runtime_put: dev=0000:00:02.0 caller_function=receive_g2h+0x2cc/0x350 [xe]
>           <idle>-0       [004] d.h2.  3821.138439: xe_pm_runtime_put: dev=0000:00:02.0 caller_function=xe_guc_ct_fast_path+0x2e4/0x430 [xe]
>    kworker/u32:0-53314   [001] .....  3821.138443: xe_pm_runtime_put: dev=0000:00:02.0 caller_function=receive_g2h+0x2cc/0x350 [xe]
>      kworker/0:1-9       [000] .....  3821.138474: xe_pm_runtime_put: dev=0000:00:02.0 caller_function=xe_ggtt_remove_node+0x1f6/0x280 [xe]
>      kworker/0:1-9       [000] .....  3821.138495: xe_pm_runtime_put: dev=0000:00:02.0 caller_function=__guc_exec_queue_fini_async+0x1b3/0x350 [xe]
>      kworker/0:0-21730   [000] .....  3821.138503: xe_pm_runtime_put: dev=0000:00:02.0 caller_function=xe_ggtt_remove_node+0x1f6/0x280 [xe]
>      kworker/0:0-21730   [000] .....  3821.138540: xe_pm_runtime_put: dev=0000:00:02.0 caller_function=__guc_exec_queue_fini_async+0x1b3/0x350 [xe]

Looks very helpful, I didn't know exactly how to get caller function in
output like this, cool.

>    kworker/u33:0-25711   [002] .....  3821.138601: xe_vm_free: dev=0000:00:02.0, vm=ffff88811185a000, asid=0x00004
>      kworker/1:6-21907   [001] .....  3822.308942: xe_pm_runtime_suspend: dev=0000:00:02.0 caller_function=xe_pci_runtime_suspend+0x3f/0x120 [xe]
>      kworker/1:6-21907   [001] .....  3822.309550: xe_exec_queue_stop: dev=0000:00:02.0, 3:0x2, gt=0, width=1, guc_id=0, guc_state=0x0, flags=0x13
> 
>  drivers/gpu/drm/xe/xe_pm.c    |  7 ++++++
>  drivers/gpu/drm/xe/xe_trace.h | 47 +++++++++++++++++++++++++++++++++++
>  2 files changed, 54 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_pm.c b/drivers/gpu/drm/xe/xe_pm.c
> index de3b5df65e48..a38452ccf033 100644
> --- a/drivers/gpu/drm/xe/xe_pm.c
> +++ b/drivers/gpu/drm/xe/xe_pm.c
> @@ -20,6 +20,7 @@
>  #include "xe_guc.h"
>  #include "xe_irq.h"
>  #include "xe_pcode.h"
> +#include "xe_trace.h"
>  #include "xe_wa.h"
>  
>  /**
> @@ -87,6 +88,7 @@ int xe_pm_suspend(struct xe_device *xe)
>  	int err;
>  
>  	drm_dbg(&xe->drm, "Suspending device\n");
> +	trace_xe_pm_suspend(xe, __builtin_return_address(0));
>  
>  	for_each_gt(gt, xe, id)
>  		xe_gt_suspend_prepare(gt);
> @@ -131,6 +133,7 @@ int xe_pm_resume(struct xe_device *xe)
>  	int err;
>  
>  	drm_dbg(&xe->drm, "Resuming device\n");
> +	trace_xe_pm_resume(xe, __builtin_return_address(0));
>  
>  	for_each_tile(tile, xe, id)
>  		xe_wa_apply_tile_workarounds(tile);
> @@ -326,6 +329,7 @@ int xe_pm_runtime_suspend(struct xe_device *xe)
>  	u8 id;
>  	int err = 0;
>  
> +	trace_xe_pm_runtime_suspend(xe, __builtin_return_address(0));
>  	/* Disable access_ongoing asserts and prevent recursive pm calls */
>  	xe_pm_write_callback_task(xe, current);
>  
> @@ -399,6 +403,7 @@ int xe_pm_runtime_resume(struct xe_device *xe)
>  	u8 id;
>  	int err = 0;
>  
> +	trace_xe_pm_runtime_resume(xe, __builtin_return_address(0));
>  	/* Disable access_ongoing asserts and prevent recursive pm calls */
>  	xe_pm_write_callback_task(xe, current);
>  
> @@ -463,6 +468,7 @@ static void pm_runtime_lockdep_prime(void)
>   */
>  void xe_pm_runtime_get(struct xe_device *xe)
>  {
> +	trace_xe_pm_runtime_get(xe, __builtin_return_address(0));
>  	pm_runtime_get_noresume(xe->drm.dev);
>  
>  	if (xe_pm_read_callback_task(xe) == current)
> @@ -478,6 +484,7 @@ void xe_pm_runtime_get(struct xe_device *xe)
>   */
>  void xe_pm_runtime_put(struct xe_device *xe)
>  {
> +	trace_xe_pm_runtime_put(xe, __builtin_return_address(0));
>  	if (xe_pm_read_callback_task(xe) == current) {
>  		pm_runtime_put_noidle(xe->drm.dev);
>  	} else {
> diff --git a/drivers/gpu/drm/xe/xe_trace.h b/drivers/gpu/drm/xe/xe_trace.h
> index baba14fb1e32..73fe28f92d48 100644
> --- a/drivers/gpu/drm/xe/xe_trace.h
> +++ b/drivers/gpu/drm/xe/xe_trace.h
> @@ -369,6 +369,53 @@ TRACE_EVENT(xe_reg_rw,
>  		  (u32)(__entry->val >> 32))
>  );
>  
> +DECLARE_EVENT_CLASS(xe_pm_runtime,
> +		    TP_PROTO(struct xe_device *xe, void *caller),
> +		    TP_ARGS(xe, caller),
> +
> +		    TP_STRUCT__entry(
> +			     __string(dev, __dev_name_xe(xe))
> +			     __field(void *, caller)
> +			     ),
> +
> +		    TP_fast_assign(
> +			   __assign_str(dev);
> +			   __entry->caller = caller;

Does it work drop the 'void *caller' argument and do this?

__entry->caller = __builtin_return_address(0);

Unsure if that will produce the correct output though but worth checking
on.

> +			   ),
> +
> +		    TP_printk("dev=%s caller_function=%pS", __get_str(dev), __entry->caller)
> +);
> +
> +DEFINE_EVENT(xe_pm_runtime, xe_pm_runtime_get,
> +		TP_PROTO(struct xe_device *xe, void *caller),
> +		TP_ARGS(xe, caller)
> +);
> +
> +DEFINE_EVENT(xe_pm_runtime, xe_pm_runtime_put,
> +	     TP_PROTO(struct xe_device *xe, void *caller),
> +	     TP_ARGS(xe, caller)

Nit the alignment looks off here.

> +);
> +
> +DEFINE_EVENT(xe_pm_runtime, xe_pm_resume,
> +		TP_PROTO(struct xe_device *xe, void *caller),
> +		TP_ARGS(xe, caller)
> +);
> +
> +DEFINE_EVENT(xe_pm_runtime, xe_pm_suspend,
> +		TP_PROTO(struct xe_device *xe, void *caller),
> +		TP_ARGS(xe, caller)
> +);
> +
> +DEFINE_EVENT(xe_pm_runtime, xe_pm_runtime_resume,
> +		TP_PROTO(struct xe_device *xe, void *caller),
> +		TP_ARGS(xe, caller)
> +);
> +
> +DEFINE_EVENT(xe_pm_runtime, xe_pm_runtime_suspend,
> +	     TP_PROTO(struct xe_device *xe, void *caller),
> +	     TP_ARGS(xe, caller)

Nit the alignment looks off here.

Also a few other look off in patchworks too, double check on all of
these.

Matt

> +);
> +
>  #endif
>  
>  /* This part must be outside protection */
> -- 
> 2.42.0
>