NameServer_get in GateMP

Ilya Shcherbak

Other Parts Discussed in Thread: SYSBIOS, TMS320C6678

Hello,

I have a dummy question. I use NameServer in my own app and need to make execution of some function a thread safe. I call GateMP_enter for that call NameServer_get in the protect section and get abort with the following error:

ti.sysbios.knl.Semaphore: line 214: assertion failure: A_pendTaskDisabled: Cannot call Semaphore_pend() while the Task or Swi scheduler is disabled.
xdc.runtime.Error.raise: terminating execution

Can I use in the protect section (between GateMP_enter and GateMP_leave) other IPC functions? For example can I use NameServer_get there?

over 12 years ago

0 Ilya Shcherbak over 12 years ago

Intellectual 680 points

There is a sample code:

foo(){
    ...
    GateMP_Handle gate=GateMP_getDefaultRemote();
   IArg key;
   NameServer_Handle ns_handler;
   UInt16 proc_list[]={0,1};
    key=GateMP_enter(gate);
   ns_handler=NameServer_getHandle("bar_table");
   int errno=NameServer_getUInt32(ns_handler,bar_key_str,(void*)bar_ptr,proc_list); - it fails after that
    ...
}

I use tms320c6678. With the follwing libraries:

bios_6_35_01_29
ipc_1_24_03_32
uia_1_03_00_02
xdctools_3_25_00_48
c6000_7.4.2

0 Arnie Reynoso over 12 years ago in reply to Ilya Shcherbak

TI__Expert 6860 points

The error being issued is due the GateMP_enter disabling the SysBios scheduler and NameServer APIs needing the scheduler enabled in order to use its Semaphore.

GateMP creates a default system gate whose handle may be obtained using GateMP_getDefaultRemote() (which you are). Most IPC modules typically use this gate by default if they require gates and no instance gate is configured by the user. In general, you shouldn't need to protect your IPC API calls.

0 Ilya Shcherbak over 12 years ago in reply to Arnie Reynoso

Intellectual 680 points

Is it possible to enable scheduler for GateMP_enter or its strongly required? For example if I need a code section that should execute monopoly and there is a several function NameServer_* in different places. How should I solve it problem? Rewrite logic of the program?

0 Arnie Reynoso over 12 years ago in reply to Ilya Shcherbak

TI__Expert 6860 points

The NameServer module using SysBios already has built-in Gate protection thus you shouldn't need to protect around these calls.

0 Ilya Shcherbak over 12 years ago in reply to Arnie Reynoso

Intellectual 680 points

Ok, I got it. Thank you for reply.

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NameServer_get in GateMP