Use conditional variable logic to synchronize between the reading and
processing threads. Currently it's done by having mutex around rotation
code.
Using a POSIX cond variable to sync both threads after queues rotation:
Process thread:
- Detects data
- Switches queues
- Sets rotate variable
- Waits in pthread_cond_wait()
Read thread:
- Detects rotate is set
- Kicks the process thread with a pthread_cond_signal()
After this rotation is safely completed and both threads can continue
with the new queue.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-3rdeg23rv3brvy1pwt3igvyw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
94ad6e7e36