Re: [PATCH v2 1/3] soc: qcom: Add tracepoints to mdt loader

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Mon 16 Nov 15:44 CST 2020, Rishabh Bhatnagar wrote:

> Add trace events to the mdt loader driver. These events
> can help us trace the region where we are loading the
> segments and the time it takes to initialize the image
> and setup the memory region.
> 
> Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>
> ---
>  drivers/soc/qcom/mdt_loader.c     |  7 +++++++
>  include/trace/events/mdt_loader.h | 38 ++++++++++++++++++++++++++++++++++++++
>  2 files changed, 45 insertions(+)
>  create mode 100644 include/trace/events/mdt_loader.h
> 
> diff --git a/drivers/soc/qcom/mdt_loader.c b/drivers/soc/qcom/mdt_loader.c
> index 24cd193..96dc912 100644
> --- a/drivers/soc/qcom/mdt_loader.c
> +++ b/drivers/soc/qcom/mdt_loader.c
> @@ -17,6 +17,9 @@
>  #include <linux/slab.h>
>  #include <linux/soc/qcom/mdt_loader.h>
>  
> +#define CREATE_TRACE_POINTS
> +#include <trace/events/mdt_loader.h>
> +
>  static bool mdt_phdr_valid(const struct elf32_phdr *phdr)
>  {
>  	if (phdr->p_type != PT_LOAD)
> @@ -198,6 +201,7 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
>  		if (pas_init) {
>  			ret = qcom_scm_pas_mem_setup(pas_id, mem_phys,
>  						     max_addr - min_addr);
> +

This change is unnecessary.

>  			if (ret) {
>  				dev_err(dev, "unable to setup relocation\n");
>  				goto out;
> @@ -232,6 +236,7 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
>  
>  		ptr = mem_region + offset;
>  
> +

Ditto.

>  		if (phdr->p_filesz && phdr->p_offset < fw->size) {
>  			/* Firmware is large enough to be non-split */
>  			if (phdr->p_offset + phdr->p_filesz > fw->size) {
> @@ -256,6 +261,8 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
>  			release_firmware(seg_fw);
>  		}
>  
> +		trace_qcom_mdt_load_segment(mem_phys + offset, phdr->p_filesz,
> +					    fw_name);
>  		if (phdr->p_memsz > phdr->p_filesz)
>  			memset(ptr + phdr->p_filesz, 0, phdr->p_memsz - phdr->p_filesz);
>  	}
> diff --git a/include/trace/events/mdt_loader.h b/include/trace/events/mdt_loader.h
> new file mode 100644
> index 0000000..01c2461
> --- /dev/null
> +++ b/include/trace/events/mdt_loader.h
> @@ -0,0 +1,38 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (c) 2020, The Linux Foundation. All rights reserved.
> + */
> +
> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM mdt_loader
> +
> +#if !defined(_TRACE_MDT_LOADER_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _TRACE_MDT_LOADER_H
> +
> +#include <linux/types.h>
> +#include <linux/tracepoint.h>
> +
> +TRACE_EVENT(qcom_mdt_load_segment,
> +
> +	TP_PROTO(phys_addr_t region_start, size_t region_size, const char *fw),
> +
> +	TP_ARGS(region_start, region_size, fw),
> +
> +	TP_STRUCT__entry(
> +		__field(phys_addr_t, region_start)
> +		__field(size_t, region_size)
> +		__string(fw, fw)
> +	),
> +
> +	TP_fast_assign(
> +		__entry->region_start = region_start;
> +		__entry->region_size = region_size;
> +		__assign_str(fw, fw);
> +	),
> +
> +	TP_printk("firmware:%s region start=%pa size=%zx",
> +		  __get_str(fw), __entry->region_start, __entry->region_size)

Doesn't this printk use the normal format specifiers, where %pa should
be passed by reference? (I.e. shouldn't this be &__entry->region_start?)

Regards,
Bjorn

> +);
> +
> +#endif
> +#include <trace/define_trace.h>
> -- 
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>