[PATCH 2/9] grep: move sha1-reading mutex into low-level code
- From
Jeff King <peff@peff.net>
- Date
- Feb 2, 2012, 08:18 UTC
- Message-ID
- <20120202081841.GB6786@sigill.intra.peff.net>
- In-Reply-To
- <20120202081747.GA10271@sigill.intra.peff.net>
The multi-threaded git-grep code needs to serialize access to the thread-unsafe read_sha1_file call. It does this with a mutex that is local to builtin/grep.c.
Let's instead push this down into grep.c, where it can be used by both builtin/grep.c and grep.c. This will let us safely teach the low-level grep.c code tricks that involve reading from the object db.
Signed-off-by: Jeff King <peff@peff.net> --- builtin/grep.c | 29 ++++++----------------------- grep.c | 6 ++++++ grep.h | 17 +++++++++++++++++ 3 files changed, 29 insertions(+), 23 deletions(-)
diff --git a/builtin/grep.c b/builtin/grep.c index 06983f9..f4402fa 100644 --- a/builtin/grep.c +++ b/builtin/grep.c @@ -85,21 +85,6 @@ static inline void grep_unlock(void) pthread_mutex_unlock(&grep_mutex); } -/* Used to serialize calls to read_sha1_file. */ -static pthread_mutex_t read_sha1_mutex; - -static inline void read_sha1_lock(void) -{ - if (use_threads) - pthread_mutex_lock(&read_sha1_mutex); -} - -static inline void read_sha1_unlock(void) -{ - if (use_threads) - pthread_mutex_unlock(&read_sha1_mutex); -} - /* Signalled when a new work_item is added to todo. */ static pthread_cond_t cond_add; @@ -254,7 +239,7 @@ static void start_threads(struct grep_opt *opt) int i; pthread_mutex_init(&grep_mutex, NULL); - pthread_mutex_init(&read_sha1_mutex, NULL); + pthread_mutex_init(&grep_read_mutex, NULL); pthread_mutex_init(&grep_attr_mutex, NULL); pthread_cond_init(&cond_add, NULL); pthread_cond_init(&cond_write, NULL); @@ -303,7 +288,7 @@ static int wait_all(void) } pthread_mutex_destroy(&grep_mutex); - pthread_mutex_destroy(&read_sha1_mutex); + pthread_mutex_destroy(&grep_read_mutex); pthread_mutex_destroy(&grep_attr_mutex); pthread_cond_destroy(&cond_add); pthread_cond_destroy(&cond_write); @@ -313,8 +298,6 @@ static int wait_all(void) return hit; } #else /* !NO_PTHREADS */ -#define read_sha1_lock() -#define read_sha1_unlock() static int wait_all(void) { @@ -376,9 +359,9 @@ static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type { void *data; - read_sha1_lock(); + grep_read_lock(); data = read_sha1_file(sha1, type, size); - read_sha1_unlock(); + grep_read_unlock(); return data; } @@ -617,10 +600,10 @@ static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec, struct strbuf base; int hit, len; - read_sha1_lock(); + grep_read_lock(); data = read_object_with_reference(obj->sha1, tree_type, &size, NULL); - read_sha1_unlock(); + grep_read_unlock(); if (!data) die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1)); diff --git a/grep.c b/grep.c index 7a67c2f..db58a29 100644 --- a/grep.c +++ b/grep.c @@ -826,6 +826,12 @@ static inline void grep_attr_unlock(void) if (grep_use_locks) pthread_mutex_unlock(&grep_attr_mutex); } + +/* + * Same as git_attr_mutex, but protecting the thread-unsafe object db access. + */ +pthread_mutex_t grep_read_mutex; + #else #define grep_attr_lock() #define grep_attr_unlock() diff --git a/grep.h b/grep.h index 3653bb3..4f1b025 100644 --- a/grep.h +++ b/grep.h @@ -139,6 +139,23 @@ extern int grep_threads_ok(const struct grep_opt *opt); */ extern int grep_use_locks; extern pthread_mutex_t grep_attr_mutex; +extern pthread_mutex_t grep_read_mutex; + +static inline void grep_read_lock(void) +{ + if (grep_use_locks) + pthread_mutex_lock(&grep_read_mutex); +} + +static inline void grep_read_unlock(void) +{ + if (grep_use_locks) + pthread_mutex_unlock(&grep_read_mutex); +} + +#else +#define grep_read_lock() +#define grep_read_unlock() #endif #endif
-- 1.7.9.3.gc3fce1.dirty