Re: [PATCH 2/2] Remove spurious 'no threads support' warnings
On Mon, Oct 13, 2014 at 9:54 PM, Junio C Hamano <gitster@pobox.com> wrote:
Show 21 quoted lines
> Etienne Buira <etienne.buira@gmail.com> writes:
>
>> Threads count being defaulted to 0 (autodetect), and --disable-pthreads
>> build checking that thread count==1, there were spurious warnings about
>> threads being ignored, despite not specified on command line/conf.
>>
>> Fixes tests 5521 and 5526 that were broken in --disable-pthreads builds
>> because of those warnings.
>>
>> Signed-off-by: Etienne Buira <etienne.buira@gmail.com>
>> ---
>
> I am not sure if this is the right fix.
>
> Shouldn't a --threads=0 from the command line (when there is a
> pack.threads configuration hardcoding some number to override it)
> give a chance to the auto detection codepath to ask online_cpus()
> and receive 1 on NO_PTHREADS build to avoid triggering the same
> warning you are squelching with this patch?
>
> That is, something like this instead, perhaps?
Indeed, your patch is better.
Show 62 quoted lines
> -- >8 --
> Subject: [PATCH] pack-objects: set number of threads before checking and warning
>
> Under NO_PTHREADS build, we warn when delta_search_threads is not
> set to 1, because that is the only sensible value on a single
> threaded build.
>
> However, the auto detection that kicks in when that variable is set
> to 0 (e.g. there is no configuration variable or command line option,
> or an explicit --threads=0 is given from the command line to override
> the pack.threads configuration to force auto-detection) was not done
> before the condition to issue this warning was tested.
>
> Move the auto-detection code and place it at an appropriate spot.
>
> Signed-off-by: Junio C Hamano <gitster@pobox.com>
> ---
> builtin/pack-objects.c | 6 ++++--
> thread-utils.h | 4 ++++
> 2 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
> index d391934..a715237 100644
> --- a/builtin/pack-objects.c
> +++ b/builtin/pack-objects.c
> @@ -1972,8 +1972,6 @@ static void ll_find_deltas(struct object_entry **list, unsigned list_size,
>
> init_threaded_search();
>
> - if (!delta_search_threads) /* --threads=0 means autodetect */
> - delta_search_threads = online_cpus();
> if (delta_search_threads <= 1) {
> find_deltas(list, &list_size, window, depth, processed);
> cleanup_threaded_search();
> @@ -2685,6 +2683,10 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
> pack_compression_level = Z_DEFAULT_COMPRESSION;
> else if (pack_compression_level < 0 || pack_compression_level > Z_BEST_COMPRESSION)
> die("bad pack compression level %d", pack_compression_level);
> +
> + if (!delta_search_threads) /* --threads=0 means autodetect */
> + delta_search_threads = online_cpus();
> +
> #ifdef NO_PTHREADS
> if (delta_search_threads != 1)
> warning("no threads support, ignoring --threads");
> diff --git a/thread-utils.h b/thread-utils.h
> index 6fb98c3..d9a769d 100644
> --- a/thread-utils.h
> +++ b/thread-utils.h
> @@ -7,5 +7,9 @@
> extern int online_cpus(void);
> extern int init_recursive_mutex(pthread_mutex_t*);
>
> +#else
> +
> +#define online_cpus() 1
> +
> #endif
> #endif /* THREAD_COMPAT_H */
> --
> 2.1.2-468-g1a77c5b
>Etienne Buira <etienne.buira@gmail.com>