Re: Re: [PATCH] fix threaded grep for machines with only one cpu
From: Heiko Voigt <hidden>
Date: 2016-06-15 22:48:17
Possibly related (same subject, not in this thread)
- 2016-06-15 · Re: Re: [PATCH] fix threaded grep for machines with only one cpu · Heiko Voigt <hidden>
- 2016-06-15 · [PATCH] fix threaded grep for machines with only one cpu · Heiko Voigt <hidden>
- 2016-06-15 · Re: [PATCH] fix threaded grep for machines with only one cpu · Johannes Schindelin <hidden>
- 2016-06-15 · Re: [PATCH] fix threaded grep for machines with only one cpu · Junio C Hamano <hidden>
- 2016-06-15 · Re: [PATCH] fix threaded grep for machines with only one cpu · Junio C Hamano <hidden>
On Mon, Feb 15, 2010 at 06:39:48PM -0800, Junio C Hamano wrote:
Junio C Hamano [off-list ref] writes:quoted
Is this the answer to my question?
Sorry I forgot to add a reference to the thread from which the patch originated: http://groups.google.com/group/msysgit/msg/5da53cf1ccf417cf
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).
Yes your patch does it correctly I just verified that the segfaults are gone as well. I think your solution is even nicer than mine. Thanks.
-- >8 -- From: Junio C Hamano <redacted> Date: Mon, 15 Feb 2010 18:34:28 -0800 Subject: [PATCH] Fix use of mutex in threaded grep
[...]
quoted hunk ↗ jump to hunk
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)
One minor thing: Would it not be even nicer having the while loop inside
the if clause? E.g like this
#define read_sha1_lock() if (use_threads) do { pthread_mutex_lock(&read_sha1_mutex); } while (0)
#define read_sha1_unlock() if (use_threads) do { pthread_mutex_unlock(&read_sha1_mutex); } while (0)
If the purpose was to force a thread switch it is not necessary when not
using threads.
cheers Heiko