You can use the below query to extract the context switches information from ring buffers and time each thread spend owning the scheduler.

SELECT  
dateadd (ms, (a.[timestamp] - tme.ms_ticks), GETDATE()) as Time_Stamp,
a.*
FROM
(SELECT 
	  y as timestamp,	
      x.value('(//Record/@id)[1]', 'bigint') AS [Record Id],
      x.value('(//Record/@type)[1]', 'varchar(30)') AS [Type],
      x.value('(//Record/@time)[1]', 'bigint') AS [Time],
      x.value('(//Record/Scheduler/@address)[1]', 'varchar(30)') AS [Scheduler Address],
      x.value('(//Record/Scheduler/Action)[1]', 'varchar(30)') AS [Scheduler Action],
      x.value('(//Record/Scheduler/CPUTicks)[1]', 'bigint') AS [Scheduler CPUTicks],
      x.value('(//Record/Scheduler/TickCount)[1]', 'bigint') AS [Scheduler TickCount],
      x.value('(//Record/Scheduler/SourceWorker)[1]', 'varchar(30)') AS [Scheduler SourceWorker],
      x.value('(//Record/Scheduler/TargetWorker)[1]', 'varchar(30)') AS [Scheduler TargetWorker],
      x.value('(//Record/Scheduler/WorkerSignalTime)[1]', 'bigint') AS [Scheduler WorkerSignalTime],
      x.value('(//Record/Scheduler/DiskIOCompleted)[1]', 'bigint') AS [Scheduler DiskIOCompleted],
      x.value('(//Record/Scheduler/TimersExpired)[1]', 'bigint') AS [Scheduler TimersExpired]
FROM
      (SELECT CAST (record as xml),timestamp  
      FROM sys.dm_os_ring_buffers 
      WHERE ring_buffer_type = 'RING_BUFFER_SCHEDULER' ) AS R(x,y)) a
	  cross join sys.dm_os_sys_info tme 
WHERE a.[Scheduler Action] = 'SCHEDULER_SWITCH_CONTEXT'
ORDER BY       a.[Scheduler Address] , [Time_stamp]