Re: [PATCH v2] Add gpu memory tracepoints

[Steven Rostedt]

On Wed, 12 Feb 2020 16:32:59 -0800
zzyiwei@xxxxxxxxxx wrote:

> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM gpu_mem
> +
> +#if !defined(_TRACE_GPU_MEM_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _TRACE_GPU_MEM_H
> +
> +#include <linux/tracepoint.h>
> +
> +/*
> + * The gpu_memory_total event indicates that there's an update to either the
> + * global or process total gpu memory counters.
> + *
> + * This event should be emitted whenever the kernel device driver allocates,
> + * frees, imports, unimports memory in the GPU addressable space.
> + *
> + * @gpu_id: This is the gpu id.
> + *
> + * @pid: Put 0 for global total, while positive pid for process total.
> + *
> + * @size: Virtual size of the allocation in bytes.
> + *
> + */
> +TRACE_EVENT(gpu_mem_total,
> +	TP_PROTO(
> +		uint32_t gpu_id,
> +		uint32_t pid,
> +		uint64_t size
> +	),
> +	TP_ARGS(
> +		gpu_id,
> +		pid,
> +		size
> +	),

This is unique whitespace parsing. Usually, this would be:

	TP_PROTO(uint32_t gpu_id, unint32_t pid, uint64_t size),

	TP_ARGS(gpu_id, pid, size),

> +	TP_STRUCT__entry(
> +		__field(uint32_t, gpu_id)
> +		__field(uint32_t, pid)
> +		__field(uint64_t, size)
> +	),
> +	TP_fast_assign(
> +		__entry->gpu_id = gpu_id;
> +		__entry->pid = pid;
> +		__entry->size = size;
> +	),
> +	TP_printk(
> +		"gpu_id=%u "
> +		"pid=%u "
> +		"size=%llu",

Breaking up a string is frowned upon.

	TP_print("gpu_id=%u pid=$u size=%llu",
		 __entry->gpu_id,
		 __entry->pid,
		 __entry->size)

-- Steve

> +		__entry->gpu_id,
> +		__entry->pid,
> +		__entry->size
> +	)
> +);
> +
> +#endif /* _TRACE_GPU_MEM_H */
> +
> +/* This part must be outside protection */
> +#include <trace/define_trace.h>