Subj : Re: Recursive mutexes
To   : comp.programming.threads
From : Marcin 'Qrczak' Kowalczyk
Date : Sun Mar 27 2005 02:55 pm

"doug" <noone@nowhere.co.uk> writes:

> void my_mutex::acquire() {
> EnterCriticalSection();
> if (m_owner == thread_id) {
>     ++m_count;
> }
> else {
>     do
> *  {
> *    ExitCriticalSection();
>       m_mutex->wait();
> *    EnterCriticalSection();
> *  } while (m_count > 0);
>     m_count = 1;
>     m_owner = thread_id;
>  }
> ExitCriticalSection();
> }

It should be while (m_count > 0) {...}, not do {...} while (m_count > 0).

Alternatively m_count should be tested at the beginning, so the common
case of the mutex being free is faster.

-- 
   __("<         Marcin Kowalczyk
   \__/       qrczak@knm.org.pl
    ^^     http://qrnik.knm.org.pl/~qrczak/

.