From 0612ad26506097b532bc097472894b342a4e9264 Mon Sep 17 00:00:00 2001 From: Till Straumann Date: Mon, 3 Nov 2008 20:23:29 +0000 Subject: 2008-11-03 Till Straumann * shared/startup/pretaskinghook.c, shared/startup/sbrk.c: Fixed PR#1335. Pass initial starting address to heap initialization to avoid 1st 'sbrk'. User may now define 'BSP_sbrk_policy' variable (see sbrk.c) to tune behavior. --- c/src/lib/libbsp/powerpc/ChangeLog | 5 +++ c/src/lib/libbsp/powerpc/shared/startup/sbrk.c | 45 +++++++++++++++++++++++++- 2 files changed, 49 insertions(+), 1 deletion(-) diff --git a/c/src/lib/libbsp/powerpc/ChangeLog b/c/src/lib/libbsp/powerpc/ChangeLog index 8ef3c4dd97..aa5f39d570 100644 --- a/c/src/lib/libbsp/powerpc/ChangeLog +++ b/c/src/lib/libbsp/powerpc/ChangeLog @@ -1,3 +1,8 @@ +2008-11-03 Till Straumann + + * shared/startup/pretaskinghook.c, shared/startup/sbrk.c: + Fixed PR#1335. + 2008-10-02 Sebastian Huber * shared/clock/clock.c: Update for status-checks.h changes. diff --git a/c/src/lib/libbsp/powerpc/shared/startup/sbrk.c b/c/src/lib/libbsp/powerpc/shared/startup/sbrk.c index 07168af8b6..1a219cf5f5 100644 --- a/c/src/lib/libbsp/powerpc/shared/startup/sbrk.c +++ b/c/src/lib/libbsp/powerpc/shared/startup/sbrk.c @@ -73,6 +73,16 @@ static uint32_t remaining_start=0; static uint32_t remaining_size=0; +/* App. may provide a value by defining the BSP_sbrk_policy + * variable. + * + * (-1) -> give all memory to the heap at initialization time + * > 0 -> value used as sbrk amount; initially give 32M + * 0 -> limit memory effectively to 32M. + * + */ +extern uint32_t BSP_sbrk_policy __attribute__((weak)); + #define LIMIT_32M 0x02000000 uintptr_t _bsp_sbrk_init( @@ -83,13 +93,42 @@ uintptr_t _bsp_sbrk_init( uintptr_t rval=0; remaining_start = heap_start; - remaining_size =* heap_size_p; + remaining_size = *heap_size_p; + if (remaining_start < LIMIT_32M && remaining_start + remaining_size > LIMIT_32M) { /* clip at LIMIT_32M */ rval = remaining_start + remaining_size - LIMIT_32M; *heap_size_p = LIMIT_32M - remaining_start; + remaining_start = LIMIT_32M; + remaining_size = rval; } + + if ( 0 != &BSP_sbrk_policy ) { + switch ( BSP_sbrk_policy ) { + case (uint32_t)(-1): + remaining_start = heap_start + *heap_size_p; + remaining_size = 0; + /* return a nonzero sbrk_amount because the libsupport code + * at some point divides by this number prior to trying an + * sbrk() which will fail. + */ + rval = 1; + break; + + case 0: + remaining_size = 0; + /* see above for why we return 1 */ + rval = 1; + break; + + default: + if ( rval > BSP_sbrk_policy ) + rval = BSP_sbrk_policy; + break; + } + } + return rval; } @@ -97,6 +136,7 @@ void * sbrk(ptrdiff_t incr) { void *rval=(void*)-1; + /* FIXME: BEWARE if size >2G */ if (incr <= remaining_size) { remaining_size-=incr; rval = (void*)remaining_start; @@ -104,5 +144,8 @@ void * sbrk(ptrdiff_t incr) } else { errno = ENOMEM; } +#ifdef DEBUG + printk("************* SBRK 0x%08x (ret 0x%08x) **********\n", incr, rval); +#endif return rval; } -- cgit v1.2.3