From 3595533de5a347ddeb5f2bb2b14a853296d23119 Mon Sep 17 00:00:00 2001 From: Sebastian Huber Date: Wed, 11 Apr 2012 10:50:00 +0200 Subject: score: Remove _Stack_Adjust_size() The increase of the stack size by CPU_STACK_ALIGNMENT in _Thread_Stack_Allocate() is disadvantageous. This may lead to a huge over allocation for specialized stack allocators. The CPU_STACK_ALIGNMENT is at most 16 on all current RTEMS CPU ports. The mimimum stack size ensured by _Stack_Ensure_minimum() must be considerable larger than this value, otherwise stack overflows will likely occur. Thus the _Stack_Adjust_size() is also superfluous. --- cpukit/score/inline/rtems/score/stack.inl | 18 ------------------ cpukit/score/src/threadstackallocate.c | 12 ------------ 2 files changed, 30 deletions(-) (limited to 'cpukit') diff --git a/cpukit/score/inline/rtems/score/stack.inl b/cpukit/score/inline/rtems/score/stack.inl index c5d809cb81..2f49d012b3 100644 --- a/cpukit/score/inline/rtems/score/stack.inl +++ b/cpukit/score/inline/rtems/score/stack.inl @@ -24,7 +24,6 @@ #define _RTEMS_SCORE_STACK_INL #include /* RTEMS_INLINE_ROUTINE */ -#include /* CPU_STACK_ALIGNMENT */ /** * @addtogroup ScoreStack @@ -90,23 +89,6 @@ RTEMS_INLINE_ROUTINE size_t _Stack_Ensure_minimum ( return _Stack_Minimum(); } -/** - * This function increases the stack size to ensure that the thread - * has the desired amount of stack space after the initial stack - * pointer is determined based on alignment restrictions. - * - * @note - * - * The amount of adjustment for alignment is CPU dependent. - */ - -RTEMS_INLINE_ROUTINE uint32_t _Stack_Adjust_size ( - size_t size -) -{ - return size + CPU_STACK_ALIGNMENT; -} - /**@}*/ #endif diff --git a/cpukit/score/src/threadstackallocate.c b/cpukit/score/src/threadstackallocate.c index 9448328365..68aa649857 100644 --- a/cpukit/score/src/threadstackallocate.c +++ b/cpukit/score/src/threadstackallocate.c @@ -51,18 +51,6 @@ size_t _Thread_Stack_Allocate( the_stack_size = _Stack_Ensure_minimum( stack_size ); - /* - * Pad the requested size so we allocate enough memory - * so the context initialization can align it properly. The address - * returned the workspace allocate must be directly stored in the - * stack control block because it is later used in the free sequence. - * - * Thus it is the responsibility of the CPU dependent code to - * get and keep the stack adjust factor, the stack alignment, and - * the context initialization sequence in sync. - */ - the_stack_size = _Stack_Adjust_size( the_stack_size ); - stack_addr = (*stack_allocate_hook)( the_stack_size ); if ( !stack_addr ) -- cgit v1.2.3