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view src/gpf/inc/nuc/old/dm_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) 1993-1996 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 */ /* */ /* dm_defs.h PLUS 1.2a */ /* */ /* COMPONENT */ /* */ /* DM - Dynamic Memory Management */ /* */ /* DESCRIPTION */ /* */ /* This file contains data structure definitions and constants for */ /* the Dynamic Memory component. */ /* */ /* AUTHOR */ /* */ /* William E. Lamie, Accelerated Technology, Inc. */ /* */ /* DATA STRUCTURES */ /* */ /* DM_PCB Dynamic Pool control block */ /* DM_HEADER Header of each memory block */ /* DM_SUSPEND Memory suspension block */ /* */ /* FUNCTIONS */ /* */ /* None */ /* */ /* DEPENDENCIES */ /* */ /* cs_defs.h Common service definitions */ /* tc_defs.h Thread 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 03-01-1994 Moved include files outside of */ /* the file #ifndef to allow the */ /* use of actual data structures, */ /* added padding logic, */ /* resulting in version 1.1 */ /* R. Pfaff - */ /* D. Lamie 03-18-1994 Verified version 1.1 */ /* M.Q. Qian 04-17-1996 updated to version 1.2 */ /* M. Trippi 01-07-1996 Added missing PAD_1 field to */ /* DM_HEADER_STRUCT to be */ /* consistent with other PLUS */ /* structures creating 1.2a. */ /* */ /*************************************************************************/ #include "cs_defs.h" /* Common service constants */ #include "tc_defs.h" /* Thread control constants */ /* Check to see if the file has been included already. */ #ifndef DM_DEFS #define DM_DEFS /* Define constants local to this component. */ #define DM_DYNAMIC_ID 0x44594e41UL #define DM_OVERHEAD ((sizeof(DM_HEADER) + sizeof(UNSIGNED) \ - 1)/sizeof(UNSIGNED)) * \ sizeof(UNSIGNED) /* Define the Dynamic Pool Control Block data type. */ typedef struct DM_PCB_STRUCT { CS_NODE dm_created; /* Node for linking to */ /* created dynamic pools */ TC_PROTECT dm_protect; /* Protection structure */ UNSIGNED dm_id; /* Internal PCB ID */ CHAR dm_name[NU_MAX_NAME]; /* Dynamic Pool name */ VOID *dm_start_address; /* Starting pool address */ UNSIGNED dm_pool_size; /* Size of pool */ UNSIGNED dm_min_allocation; /* Minimum allocate size */ UNSIGNED dm_available; /* Total available bytes */ struct DM_HEADER_STRUCT *dm_memory_list; /* Memory list */ struct DM_HEADER_STRUCT *dm_search_ptr; /* Search pointer */ DATA_ELEMENT dm_fifo_suspend; /* Suspension type flag */ #if PAD_1 DATA_ELEMENT dm_padding[PAD_1]; #endif UNSIGNED dm_tasks_waiting; /* Number of waiting tasks*/ struct DM_SUSPEND_STRUCT *dm_suspension_list; /* Suspension list */ } DM_PCB; /* Define the header structure that is in front of each memory block. */ typedef struct DM_HEADER_STRUCT { struct DM_HEADER_STRUCT *dm_next_memory, /* Next memory block */ *dm_previous_memory; /* Previous memory block */ DATA_ELEMENT dm_memory_free; /* Memory block free flag */ #if PAD_1 DATA_ELEMENT dm_padding[PAD_1]; #endif DM_PCB *dm_memory_pool; /* Dynamic pool pointer */ } DM_HEADER; /* Define the dynamic memory suspension structure. This structure is allocated off of the caller's stack. */ typedef struct DM_SUSPEND_STRUCT { CS_NODE dm_suspend_link; /* Link to suspend blocks */ DM_PCB *dm_memory_pool; /* Pointer to pool */ UNSIGNED dm_request_size; /* Size of memory request */ TC_TCB *dm_suspended_task; /* Task suspended */ VOID *dm_return_pointer; /* Return memory address */ STATUS dm_return_status; /* Return status */ } DM_SUSPEND; #endif