FreeCalypso > hg > fc-tourmaline
view src/cs/os/nucleus/tc_defs.h @ 220:0ed36de51973
ABB semaphore protection overhaul
The ABB semaphone protection logic that came with TCS211 from TI
was broken in several ways:
* Some semaphore-protected functions were called from Application_Initialize()
context. NU_Obtain_Semaphore() called with NU_SUSPEND fails with
NU_INVALID_SUSPEND in this context, but the return value wasn't checked,
and NU_Release_Semaphore() would be called unconditionally at the end.
The latter call would increment the semaphore count past 1, making the
semaphore no longer binary and thus no longer effective for resource
protection. The fix is to check the return value from NU_Obtain_Semaphore()
and skip the NU_Release_Semaphore() call if the semaphore wasn't properly
obtained.
* Some SPI hardware manipulation was being done before entering the semaphore-
protected critical section. The fix is to reorder the code: first obtain
the semaphore, then do everything else.
* In the corner case of L1/DSP recovery, l1_abb_power_on() would call some
non-semaphore-protected ABB & SPI init functions. The fix is to skip those
calls in the case of recovery.
* A few additional corner cases existed, all of which are fixed by making
ABB semaphore protection 100% consistent for all ABB functions and code paths.
There is still one remaining problem of priority inversion: suppose a low-
priority task calls an ABB function, and some medium-priority task just happens
to preempt right in the middle of that semaphore-protected ABB operation. Then
the high-priority SPI task is locked out for a non-deterministic time until
that medium-priority task finishes its work and goes back to sleep. This
priority inversion problem remains outstanding for now.
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Mon, 26 Apr 2021 20:55:25 +0000 |
| parents | 4e78acac3d88 |
| children |
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/*************************************************************************/ /* */ /* Copyright (c) 1993-1994 Accelerated Technology, Inc. */ /* */ /* PROPRIETARY RIGHTS of Accelerated Technology are involved in the */ /* subject matter of this material. All manufacturing, reproduction, */ /* use, and sales rights pertaining to this subject matter are governed */ /* by the license agreement. The recipient of this software implicitly */ /* accepts the terms of the license. */ /* */ /*************************************************************************/ /*************************************************************************/ /* */ /* FILE NAME VERSION */ /* */ /* tc_defs.h PLUS 1.1 */ /* */ /* COMPONENT */ /* */ /* TC - Thread Control */ /* */ /* DESCRIPTION */ /* */ /* This file contains data structure definitions and constants for */ /* the component that controls the various threads of execution in */ /* system. Threads include tasks, HISRs, signal handlers, etc. */ /* */ /* AUTHOR */ /* */ /* William E. Lamie, Accelerated Technology, Inc. */ /* */ /* DATA STRUCTURES */ /* */ /* TC_TCB Task Control Block */ /* TC_HCB HISR Control Block */ /* TC_PROTECT Task/HISR protection struct */ /* */ /* FUNCTIONS */ /* */ /* None */ /* */ /* DEPENDENCIES */ /* */ /* cs_defs.h Common service definitions */ /* tm_defs.h Timer control definitions */ /* */ /* HISTORY */ /* */ /* NAME DATE REMARKS */ /* */ /* W. Lamie 03-01-1993 Created initial version 1.0 */ /* D. Lamie 04-19-1993 Verified version 1.0 */ /* W. Lamie 06-01-1993 Added padding conditional into */ /* TC_TCB structure, making */ /* version 1.0a */ /* D. Lamie 06-01-1993 Verified version 1.0a */ /* W. Lamie 03-01-1994 Moved include files outside of */ /* the file #ifndef to allow the */ /* use of actual data structures, */ /* added four reserved words in */ /* both the task and HISR blocks, */ /* resulting in version 1.1 */ /* R. Pfaff - */ /* D. Lamie 03-18-1994 Verified version 1.1 */ /* */ /*************************************************************************/ #include "cs_defs.h" /* Common service constants */ #include "tm_defs.h" /* Timer control structures */ /* Check to see if the file has been included already. */ #ifndef TC_DEFS #define TC_DEFS /* Define constants local to this component. */ #define TC_TASK_ID 0x5441534bUL #define TC_HISR_ID 0x48495352UL #define TC_PRIORITIES 256 #define TC_HISR_PRIORITIES 3 #define TC_MAX_GROUPS TC_PRIORITIES/8 #define TC_HIGHEST_MASK 0x000000FFUL #define TC_NEXT_HIGHEST_MASK 0x0000FF00UL #define TC_NEXT_LOWEST_MASK 0x00FF0000UL #define TC_LOWEST_MASK 0xFF000000UL /* Define the Task Control Block data type. */ typedef struct TC_TCB_STRUCT { /* Standard thread information first. This information is used by the target dependent portion of this component. Changes made to this area of the structure can have undesirable side effects. */ CS_NODE tc_created; /* Node for linking to */ /* created task list */ UNSIGNED tc_id; /* Internal TCB ID */ CHAR tc_name[NU_MAX_NAME]; /* Task name */ DATA_ELEMENT tc_status; /* Task status */ DATA_ELEMENT tc_delayed_suspend; /* Delayed task suspension*/ DATA_ELEMENT tc_priority; /* Task priority */ DATA_ELEMENT tc_preemption; /* Task preemption enable */ UNSIGNED tc_scheduled; /* Task scheduled count */ UNSIGNED tc_cur_time_slice; /* Current time slice */ VOID *tc_stack_start; /* Stack starting address */ VOID *tc_stack_end; /* Stack ending address */ VOID *tc_stack_pointer; /* Task stack pointer */ UNSIGNED tc_stack_size; /* Task stack's size */ UNSIGNED tc_stack_minimum; /* Minimum stack size */ struct TC_PROTECT_STRUCT *tc_current_protect; /* Current protection */ VOID *tc_saved_stack_ptr; /* Previous stack pointer */ UNSIGNED tc_time_slice; /* Task time slice value */ /* Information after this point is not used in the target dependent portion of this component. Hence, changes in the following section should not impact assembly language routines. */ struct TC_TCB_STRUCT *tc_ready_previous, /* Previously ready TCB */ *tc_ready_next; /* next and previous ptrs */ /* Task control information follows. */ UNSIGNED tc_priority_group; /* Priority group mask bit*/ struct TC_TCB_STRUCT **tc_priority_head; /* Pointer to list head */ DATA_ELEMENT *tc_sub_priority_ptr; /* Pointer to sub-group */ DATA_ELEMENT tc_sub_priority; /* Mask of sub-group bit */ DATA_ELEMENT tc_saved_status; /* Previous task status */ DATA_ELEMENT tc_signal_active; /* Signal active flag */ #if PAD_3 DATA_ELEMENT tc_padding[PAD_3]; #endif /* Task entry function */ VOID (*tc_entry)(UNSIGNED, VOID *); UNSIGNED tc_argc; /* Optional task argument */ VOID *tc_argv; /* Optional task argument */ VOID (*tc_cleanup) (VOID *);/* Clean-up routine */ VOID *tc_cleanup_info; /* Clean-up information */ struct TC_PROTECT_STRUCT *tc_suspend_protect; /* Protection at time of */ /* task suspension */ /* Task timer information. */ INT tc_timer_active; /* Active timer flag */ TM_TCB tc_timer_control; /* Timer control block */ /* Task signal control information. */ UNSIGNED tc_signals; /* Current signals */ UNSIGNED tc_enabled_signals; /* Enabled signals */ /* tc_saved_status and tc_signal_active are now defined above in an attempt to keep DATA_ELEMENT types together. */ /* Signal handling routine. */ VOID (*tc_signal_handler) (UNSIGNED); /* Reserved words for the system and a single reserved word for the application. */ UNSIGNED tc_system_reserved_1; /* System reserved word */ UNSIGNED tc_system_reserved_2; /* System reserved word */ UNSIGNED tc_system_reserved_3; /* System reserved word */ UNSIGNED tc_app_reserved_1; /* Application reserved */ } TC_TCB; /* Define the High-Level Interrupt Service Routine Control Block data type. */ typedef struct TC_HCB_STRUCT { /* Standard thread information first. This information is used by the target dependent portion of this component. Changes made to this area of the structure can have undesirable side effects. */ CS_NODE tc_created; /* Node for linking to */ /* created task list */ UNSIGNED tc_id; /* Internal TCB ID */ CHAR tc_name[NU_MAX_NAME]; /* HISR name */ DATA_ELEMENT tc_not_used_1; /* Not used field */ DATA_ELEMENT tc_not_used_2; /* Not used field */ DATA_ELEMENT tc_priority; /* HISR priority */ DATA_ELEMENT tc_not_used_3; /* Not used field */ UNSIGNED tc_scheduled; /* HISR scheduled count */ UNSIGNED tc_cur_time_slice; /* Not used in HISR */ VOID *tc_stack_start; /* Stack starting address */ VOID *tc_stack_end; /* Stack ending address */ VOID *tc_stack_pointer; /* HISR stack pointer */ UNSIGNED tc_stack_size; /* HISR stack's size */ UNSIGNED tc_stack_minimum; /* Minimum stack size */ struct TC_PROTECT_STRUCT *tc_current_protect; /* Current protection */ struct TC_HCB_STRUCT *tc_active_next; /* Next activated HISR */ /* Information after this point is not used in the target dependent portion of this component. Hence, changes in the following section should not impact assembly language routines. */ UNSIGNED tc_activation_count; /* Activation counter */ VOID (*tc_entry)(VOID); /* HISR entry function */ /* Reserved words for the system and a single reserved word for the application. */ UNSIGNED tc_system_reserved_1; /* System reserved word */ UNSIGNED tc_system_reserved_2; /* System reserved word */ UNSIGNED tc_system_reserved_3; /* System reserved word */ UNSIGNED tc_app_reserved_1; /* Application reserved */ } TC_HCB; /* Define the Task/HISR protection structure type. */ typedef struct TC_PROTECT_STRUCT { TC_TCB *tc_tcb_pointer; /* Owner of the protection */ UNSIGNED tc_thread_waiting; /* Waiting thread flag */ } TC_PROTECT; #endif