From: Jeff Hostetler <git@jeffhostetler.com>
Date: Thu, 01 Oct 2020 15:53:28 GMT
Subject: Re: [PATCH v2 08/19] entry: move conv_attrs lookup up to checkout_entry()
Message-ID: <0b7d7704-159f-c186-9551-1989af8f572d@jeffhostetler.com>
In-Reply-To: <667ad0dea70cb7f0bbf8f52467f15129b3ae1325.1600814153.git.matheus.bernardino@usp.br>



On 9/22/20 6:49 PM, Matheus Tavares wrote:
> In a following patch, checkout_entry() will use conv_attrs to decide
> whether an entry should be enqueued for parallel checkout or not. But
> the attributes lookup only happens lower in this call stack. To avoid
> the unnecessary work of loading the attributes twice, let's move it up
> to checkout_entry(), and pass the loaded struct down to write_entry().
> 
> Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
> ---
>   entry.c | 38 +++++++++++++++++++++++++++-----------
>   1 file changed, 27 insertions(+), 11 deletions(-)
> 
> diff --git a/entry.c b/entry.c
> index 1d2df188e5..8237859b12 100644
> --- a/entry.c
> +++ b/entry.c
> @@ -263,8 +263,9 @@ void update_ce_after_write(const struct checkout *state, struct cache_entry *ce,
>   	}
>   }
>   
> -static int write_entry(struct cache_entry *ce,
> -		       char *path, const struct checkout *state, int to_tempfile)
> +/* Note: ca is used (and required) iff the entry refers to a regular file. */
> +static int write_entry(struct cache_entry *ce, char *path, struct conv_attrs *ca,
> +		       const struct checkout *state, int to_tempfile)
>   {
>   	unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
>   	struct delayed_checkout *dco = state->delayed_checkout;
> @@ -281,8 +282,7 @@ static int write_entry(struct cache_entry *ce,
>   	clone_checkout_metadata(&meta, &state->meta, &ce->oid);
>   
>   	if (ce_mode_s_ifmt == S_IFREG) {
> -		struct stream_filter *filter = get_stream_filter(state->istate, ce->name,
> -								 &ce->oid);
> +		struct stream_filter *filter = get_stream_filter_ca(ca, &ce->oid);
>   		if (filter &&
>   		    !streaming_write_entry(ce, path, filter,
>   					   state, to_tempfile,
> @@ -329,14 +329,17 @@ static int write_entry(struct cache_entry *ce,
>   		 * Convert from git internal format to working tree format
>   		 */
>   		if (dco && dco->state != CE_NO_DELAY) {
> -			ret = async_convert_to_working_tree(state->istate, ce->name, new_blob,
> -							    size, &buf, &meta, dco);
> +			ret = async_convert_to_working_tree_ca(ca, ce->name,
> +							       new_blob, size,
> +							       &buf, &meta, dco);
>   			if (ret && string_list_has_string(&dco->paths, ce->name)) {
>   				free(new_blob);
>   				goto delayed;
>   			}
> -		} else
> -			ret = convert_to_working_tree(state->istate, ce->name, new_blob, size, &buf, &meta);
> +		} else {
> +			ret = convert_to_working_tree_ca(ca, ce->name, new_blob,
> +							 size, &buf, &meta);
> +		}
>   
>   		if (ret) {
>   			free(new_blob);
> @@ -442,6 +445,7 @@ int checkout_entry(struct cache_entry *ce, const struct checkout *state,
>   {
>   	static struct strbuf path = STRBUF_INIT;
>   	struct stat st;
> +	struct conv_attrs ca;

I have to wonder if it would be clearer to move this declaration of `ca`
into the two `if { ... }` blocks where it is used -- to indicate that it
is only defined in two cases where we call `convert_attrs()`.

There are several other calls to `write_entry()` that pass NULL and it
could cause confusion.


>   
>   	if (ce->ce_flags & CE_WT_REMOVE) {
>   		if (topath)
> @@ -454,8 +458,13 @@ int checkout_entry(struct cache_entry *ce, const struct checkout *state,
>   		return 0;
>   	}
>   
> -	if (topath)
> -		return write_entry(ce, topath, state, 1);
> +	if (topath) {
> +		if (S_ISREG(ce->ce_mode)) {
> +			convert_attrs(state->istate, &ca, ce->name);
> +			return write_entry(ce, topath, &ca, state, 1);
> +		}
> +		return write_entry(ce, topath, NULL, state, 1);
> +	}
>   
>   	strbuf_reset(&path);
>   	strbuf_add(&path, state->base_dir, state->base_dir_len);
> @@ -517,9 +526,16 @@ int checkout_entry(struct cache_entry *ce, const struct checkout *state,
>   		return 0;
>   
>   	create_directories(path.buf, path.len, state);
> +
>   	if (nr_checkouts)
>   		(*nr_checkouts)++;
> -	return write_entry(ce, path.buf, state, 0);
> +
> +	if (S_ISREG(ce->ce_mode)) {
> +		convert_attrs(state->istate, &ca, ce->name);
> +		return write_entry(ce, path.buf, &ca, state, 0);
> +	}
> +
> +	return write_entry(ce, path.buf, NULL, state, 0);
>   }
>   
>   void unlink_entry(const struct cache_entry *ce)
>