On 8/10/19 12:53 pm, Mathew Benson wrote: > I'm using RTEMS 5 on a LEON3. I'm troubleshooting a failure condition that > occurs when stress test reading and writing to and from RAM disk. RAM disk to > RAM disk. When the condition is tripped, it appears that I have 4 tasks that > are pending on conditions that just never happens.
Do you have a test case? > The task command shows: > > ID NAME SHED PRI STATE MODES EVENTS WAITINFO > ------------------------------------------------------------------------------ > 0a01000c TSKA UPD 135 MTX P:T:nA NONE RFS > 0a01001f TSKB UPD 135 CV P:T:nA NONE bdbuf access > 0a010020 TSKC UPD 150 MTX P:T:nA NONE RFS > 0a010032 TSKD UPD 245 MTX P:T:nA NONE RFS It looks like TSKA, TSKC and TSKD are waiting for the RFS lock and TSKB is blocked in a bdbuf access. I wonder why that is blocked? The RFS hold's it lock over the bdbuf calls. > > None of my tasks appear to be failed. Nobody is pending on anything > noticeable > except the 4 above. The conditional wait is a single shared resource so any > attempt to access the file system after this happens results in yet another > forever pended task. > > Digging into source code, it appears that the kernel is waiting for a specific > response from a block device, but just didn't get what its expecting. The > next > thing is to determine which block device the kernel is pending on, what the > expected response is, and what the block device actually did. Can anybody > shed > some light on this or recommend some debugging steps? I'm trying to exhaust > all I can do before I start manually decoding machine code. The RFS has trace support you can access via `rtems/rfs/rtems-rfs-trace.h`. You can set the trace mask in your code or you can can call `rtems_rfs_trace_shell_command()` with suitable arguments or hook it to an existing shell. There is a buffer trace flag that show the release calls to bdbuf .. RTEMS_RFS_TRACE_BUFFER_RELEASE There is no trace call to get or read. Maybe add a get/read trace as well. The RAM disk also has trace in the code which can be enabled by editing the file. Chris _______________________________________________ users mailing list users@rtems.org http://lists.rtems.org/mailman/listinfo/users
