Re: [PATCH v3 dwarves 1/5] dwarf_loader: introduce pre_load_module hook to conf_load

[Alan Maguire <alan.maguire@oracle.com>]

On 16/10/2024 01:10, Ihor Solodrai wrote:
> Add a function pointer to conf_load, which is called immediately after
> Elf is extracted from Dwfl_Module in cus__proces_dwflmod.
> 
> This is a preparation for making elf_functions table shared between
> encoders. Shared table can be built as soon as the relevant Elf is
> available.
> 
> Signed-off-by: Ihor Solodrai <ihor.solodrai@pm.me>

looks good to me

Reviewed-by: Alan Maguire <alan.maguire@oracle.com>

> ---
>  dwarf_loader.c | 14 +++++++-------
>  dwarves.h      | 11 +++++++++--
>  2 files changed, 16 insertions(+), 9 deletions(-)
> 
> diff --git a/dwarf_loader.c b/dwarf_loader.c
> index e54a16c..83a7f54 100644
> --- a/dwarf_loader.c
> +++ b/dwarf_loader.c
> @@ -3723,13 +3723,6 @@ static int cus__load_module(struct cus *cus, struct conf_load *conf,
>  	return DWARF_CB_OK;
>  }
>  
> -struct process_dwflmod_parms {
> -	struct cus	 *cus;
> -	struct conf_load *conf;
> -	const char	 *filename;
> -	uint32_t	 nr_dwarf_sections_found;
> -};
> -
>  static int cus__process_dwflmod(Dwfl_Module *dwflmod,
>  				void **userdata __maybe_unused,
>  				const char *name __maybe_unused,
> @@ -3753,11 +3746,18 @@ static int cus__process_dwflmod(Dwfl_Module *dwflmod,
>  	Dwarf *dw = dwfl_module_getdwarf(dwflmod, &dwbias);
>  
>  	int err = DWARF_CB_OK;
> +	if (parms->conf->pre_load_module) {
> +		err = parms->conf->pre_load_module(dwflmod, elf);
> +		if (err)
> +			return DWARF_CB_ABORT;
> +	}
> +
>  	if (dw != NULL) {
>  		++parms->nr_dwarf_sections_found;
>  		err = cus__load_module(cus, parms->conf, dwflmod, dw, elf,
>  				       parms->filename);
>  	}
> +
>  	/*
>  	 * XXX We will fall back to try finding other debugging
>  	 * formats (CTF), so no point in telling this to the user
> diff --git a/dwarves.h b/dwarves.h
> index f147b2b..eb3be6e 100644
> --- a/dwarves.h
> +++ b/dwarves.h
> @@ -36,6 +36,7 @@
>  #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
>  
>  struct cu;
> +struct cus;
>  
>  enum load_steal_kind {
>  	LSK__KEEPIT,
> @@ -58,6 +59,13 @@ typedef uint32_t type_id_t;
>  struct btf;
>  struct conf_fprintf;
>  
> +struct process_dwflmod_parms {
> +	struct cus	 *cus;
> +	struct conf_load *conf;
> +	const char	 *filename;
> +	uint32_t	 nr_dwarf_sections_found;
> +};
> +
>  /** struct conf_load - load configuration
>   * @thread_exit - called at the end of a thread, 1st user: BTF encoder dedup
>   * @extra_dbg_info - keep original debugging format extra info
> @@ -106,6 +114,7 @@ struct conf_load {
>  	struct conf_fprintf	*conf_fprintf;
>  	int			(*threads_prepare)(struct conf_load *conf, int nr_threads, void **thr_data);
>  	int			(*threads_collect)(struct conf_load *conf, int nr_threads, void **thr_data, int error);
> +	int			(*pre_load_module)(Dwfl_Module *mod, Elf *elf);
>  };
>  
>  /** struct conf_fprintf - hints to the __fprintf routines
> @@ -167,8 +176,6 @@ struct conf_fprintf {
>  	uint8_t    skip_emitting_modifier:1;
>  };
>  
> -struct cus;
> -
>  struct cus *cus__new(void);
>  void cus__delete(struct cus *cus);
>