From: Fredrik Kuivinen Date: Tue, 16 Feb 2010 07:54:00 GMT Subject: Re: [PATCH] fix threaded grep for machines with only one cpu Message-ID: <4c8ef71002152354s3be9503aja28e5426a735ca07@mail.gmail.com> In-Reply-To: <7vljetlx8r.fsf@alter.siamese.dyndns.org> On Tue, Feb 16, 2010 at 03:39, Junio C Hamano wrote: > Junio C Hamano writes: > >> Is this the answer to my question? > > IOW, please try this patch.  I am planning to queue it to 'maint' as part > of 1.7.0.1 if this is the right solution (which I obviously think it is). > > -- >8 -- > From: Junio C Hamano > Date: Mon, 15 Feb 2010 18:34:28 -0800 > Subject: [PATCH] Fix use of mutex in threaded grep > > The program can decide at runtime not to use threading even if the > support is compiled in.  In such a case, mutexes are not necessary > and left uninitialized.  But the code incorrectly tried to take and > release the read_sha1_mutex unconditionally. > > Signed-off-by: Junio C Hamano > --- >  builtin-grep.c |    4 ++-- >  1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/builtin-grep.c b/builtin-grep.c > index 26d4deb..5c1545e 100644 > --- a/builtin-grep.c > +++ b/builtin-grep.c > @@ -81,8 +81,8 @@ static pthread_mutex_t read_sha1_mutex; > >  #define grep_lock() pthread_mutex_lock(&grep_mutex) >  #define grep_unlock() pthread_mutex_unlock(&grep_mutex) > -#define read_sha1_lock() pthread_mutex_lock(&read_sha1_mutex) > -#define read_sha1_unlock() pthread_mutex_unlock(&read_sha1_mutex) > +#define read_sha1_lock() do { if (use_threads) pthread_mutex_lock(&read_sha1_mutex); } while (0) > +#define read_sha1_unlock() do { if (use_threads) pthread_mutex_unlock(&read_sha1_mutex); } while (0) > >  /* Signalled when a new work_item is added to todo. */ >  static pthread_cond_t cond_add; This is the correct fix. Thanks. Acked-by: Fredrik Kuivinen - Fredrik