* thread.cc (pthread_rwlock::add_reader): Perform new operation here and return

pointer to allocated RWLOCK_READER structure.
(pthread_rwlock::rdlock): Reorganize to reflect new add_reader functionality.
(pthread_rwlock::tryrdlock): Ditto.  Remove unneeded call to lookup_reader().
* thread.h (pthread_rwlock::RWLOCK_READER::RWLOCK_READER): New constructor.
(pthread_rwlock::add_reader): Reflect new functionality.
This commit is contained in:
Christopher Faylor 2013-01-07 16:01:10 +00:00
parent 6cb6ea9cb4
commit 8f3f61eb96
3 changed files with 27 additions and 19 deletions

View File

@ -1,3 +1,15 @@
2013-01-07 Christopher Faylor <me.cygwin2013@cgf.cx>
* thread.cc (pthread_rwlock::add_reader): Perform new operation here
and return pointer to allocated RWLOCK_READER structure.
(pthread_rwlock::rdlock): Reorganize to reflect new add_reader
functionality.
(pthread_rwlock::tryrdlock): Ditto. Remove unneeded call to
lookup_reader().
* thread.h (pthread_rwlock::RWLOCK_READER::RWLOCK_READER): New
constructor.
(pthread_rwlock::add_reader): Reflect new functionality.
2013-01-03 Christopher Faylor <me.cygwin2013@cgf.cx>
* globals.cc (exit_states): Renumber so that ES_EXIT_STARTING is first,

View File

@ -1391,8 +1391,9 @@ pthread_rwlock::rdlock ()
goto DONE;
}
reader = new struct RWLOCK_READER;
if (!reader)
if ((reader = add_reader ()))
++reader->n;
else
{
result = EAGAIN;
goto DONE;
@ -1409,9 +1410,6 @@ pthread_rwlock::rdlock ()
pthread_cleanup_pop (0);
}
reader->thread = self;
reader->n = 1;
add_reader (reader);
DONE:
mtx.unlock ();
@ -1427,21 +1425,15 @@ pthread_rwlock::tryrdlock ()
mtx.lock ();
if (writer || waiting_writers || lookup_reader (self))
if (writer || waiting_writers)
result = EBUSY;
else
{
struct RWLOCK_READER *reader;
reader = lookup_reader (self);
RWLOCK_READER *reader = lookup_reader (self);
if (!reader)
reader = add_reader ();
if (reader && reader->n < ULONG_MAX)
++reader->n;
else if ((reader = new struct RWLOCK_READER))
{
reader->thread = self;
reader->n = 1;
add_reader (reader);
}
else
result = EAGAIN;
}
@ -1544,10 +1536,13 @@ pthread_rwlock::unlock ()
return result;
}
void
pthread_rwlock::add_reader (struct RWLOCK_READER *rd)
pthread_rwlock::RWLOCK_READER *
pthread_rwlock::add_reader ()
{
RWLOCK_READER *rd = new RWLOCK_READER;
if (rd)
List_insert (readers, rd);
return rd;
}
void

View File

@ -555,6 +555,7 @@ public:
struct RWLOCK_READER *next;
pthread_t thread;
unsigned long n;
RWLOCK_READER (): next (NULL), thread (pthread::self ()), n (0) {}
} *readers;
fast_mutex readers_mx;
@ -583,7 +584,7 @@ public:
private:
static List<pthread_rwlock> rwlocks;
void add_reader (struct RWLOCK_READER *rd);
RWLOCK_READER *add_reader ();
void remove_reader (struct RWLOCK_READER *rd);
struct RWLOCK_READER *lookup_reader (pthread_t thread);