Merge branch 'bugfix/tls_threadptr_calculation' into 'master'

freertos: fix TLS run-time address calculation

See merge request espressif/esp-idf!13271
This commit is contained in:
Angus Gratton 2021-04-21 23:13:13 +00:00
commit f91d6c7a69
6 changed files with 66 additions and 15 deletions

View File

@ -232,7 +232,6 @@ SECTIONS
ASSERT(((_bss_end - ORIGIN(dram0_0_seg)) <= LENGTH(dram0_0_seg)),
"DRAM segment data does not fit.")
/* When modifying the alignment, update tls_section_alignment in pxPortInitialiseStack */
.flash.appdesc : ALIGN(0x10)
{
_rodata_start = ABSOLUTE(.);
@ -248,6 +247,8 @@ SECTIONS
.flash.rodata : ALIGN(0x10)
{
_flash_rodata_start = ABSOLUTE(.);
mapping[flash_rodata]
@ -305,6 +306,8 @@ SECTIONS
. = ALIGN(4);
} >default_rodata_seg
_flash_rodata_align = ALIGNOF(.flash.rodata);
.flash.text :
{
_stext = .;

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@ -262,7 +262,6 @@ SECTIONS
_rodata_reserved_start = .;
} > default_rodata_seg
/* When modifying the alignment, don't forget to update tls_section_alignment in pxPortInitialiseStack */
.flash.appdesc : ALIGN(0x10)
{
_rodata_start = ABSOLUTE(.);
@ -278,6 +277,8 @@ SECTIONS
.flash.rodata : ALIGN(0x10)
{
_flash_rodata_start = ABSOLUTE(.);
mapping[flash_rodata]
*(.irom1.text) /* catch stray ICACHE_RODATA_ATTR */

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@ -251,7 +251,6 @@ SECTIONS
_bss_end = ABSOLUTE(.);
} > dram0_0_seg
/* When modifying the alignment, update tls_section_alignment in pxPortInitialiseStack */
.flash.appdesc : ALIGN(0x10)
{
_rodata_reserved_start = ABSOLUTE(.);
@ -268,6 +267,8 @@ SECTIONS
.flash.rodata : ALIGN(0x10)
{
_flash_rodata_start = ABSOLUTE(.);
mapping[flash_rodata]
*(.irom1.text) /* catch stray ICACHE_RODATA_ATTR */
@ -324,6 +325,8 @@ SECTIONS
. = ALIGN(4);
} >default_rodata_seg
_flash_rodata_align = ALIGNOF(.flash.rodata);
.flash.text :
{
_stext = .;

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@ -293,7 +293,6 @@ SECTIONS
_rodata_reserved_start = .;
} > default_rodata_seg
/* When modifying the alignment, don't forget to update tls_section_alignment in pxPortInitialiseStack */
.flash.appdesc : ALIGN(0x10)
{
_rodata_start = ABSOLUTE(.);
@ -309,6 +308,8 @@ SECTIONS
.flash.rodata : ALIGN(0x10)
{
_flash_rodata_start = ABSOLUTE(.);
mapping[flash_rodata]
*(.irom1.text) /* catch stray ICACHE_RODATA_ATTR */
@ -362,6 +363,8 @@ SECTIONS
. = ALIGN(4);
} > default_rodata_seg
_flash_rodata_align = ALIGNOF(.flash.rodata);
/* Marks the end of IRAM code segment */
.iram0.text_end (NOLOAD) :
{

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@ -224,18 +224,58 @@ StackType_t *pxPortInitialiseStack(StackType_t *pxTopOfStack, TaskFunction_t pxC
extern uint32_t __global_pointer$;
uint8_t* task_thread_local_start;
uint8_t* threadptr;
extern char _thread_local_start, _thread_local_end, _rodata_start;
extern char _thread_local_start, _thread_local_end, _flash_rodata_start;
/* Byte pointer, so that subsequent calculations don't depend on sizeof(StackType_t). */
uint8_t* sp = (uint8_t*) pxTopOfStack;
/* Set up TLS area */
/* Set up TLS area.
* The following diagram illustrates the layout of link-time and run-time
* TLS sections.
*
* +-------------+
* |Section: | Linker symbols:
* |.flash.rodata| ---------------
* 0x0+-------------+ <-- _flash_rodata_start
* ^ | |
* | | Other data |
* | | ... |
* | +-------------+ <-- _thread_local_start
* | |.tbss | ^
* v | | |
* 0xNNNN|int example; | | (thread_local_size)
* |.tdata | v
* +-------------+ <-- _thread_local_end
* | Other data |
* | ... |
* | |
* +-------------+
*
* Local variables of
* pxPortInitialiseStack
* -----------------------
* +-------------+ <-- pxTopOfStack
* |.tdata (*) | ^
* ^ |int example; | |(thread_local_size
* | | | |
* | |.tbss (*) | v
* | +-------------+ <-- task_thread_local_start
* 0xNNNN | | | ^
* | | | |
* | | | |_thread_local_start - _rodata_start
* | | | |
* | | | v
* v +-------------+ <-- threadptr
*
* (*) The stack grows downward!
*/
uint32_t thread_local_sz = (uint32_t) (&_thread_local_end - &_thread_local_start);
thread_local_sz = ALIGNUP(0x10, thread_local_sz);
sp -= thread_local_sz;
task_thread_local_start = sp;
memcpy(task_thread_local_start, &_thread_local_start, thread_local_sz);
threadptr = task_thread_local_start - (&_thread_local_start - &_rodata_start);
threadptr = task_thread_local_start - (&_thread_local_start - &_flash_rodata_start);
/* Simulate the stack frame as it would be created by a context switch interrupt. */
sp -= RV_STK_FRMSZ;

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@ -189,7 +189,7 @@ StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t px
#endif
uint32_t *threadptr;
void *task_thread_local_start;
extern int _thread_local_start, _thread_local_end, _rodata_start;
extern int _thread_local_start, _thread_local_end, _flash_rodata_start, _flash_rodata_align;
// TODO: check that TLS area fits the stack
uint32_t thread_local_sz = (uint8_t *)&_thread_local_end - (uint8_t *)&_thread_local_start;
@ -248,24 +248,25 @@ StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t px
frame->vpri = 0xFFFFFFFF;
#endif
/* Init threadptr reg and TLS vars */
/* Init threadptr register and set up TLS run-time area.
* The diagram in port/riscv/port.c illustrates the calculations below.
*/
task_thread_local_start = (void *)(((uint32_t)pxTopOfStack - XT_CP_SIZE - thread_local_sz) & ~0xf);
memcpy(task_thread_local_start, &_thread_local_start, thread_local_sz);
threadptr = (uint32_t *)(sp + XT_STK_EXTRA);
/* Calculate THREADPTR value:
/* Calculate THREADPTR value.
* The generated code will add THREADPTR value to a constant value determined at link time,
* to get the address of the TLS variable.
* The constant value is calculated by the linker as follows
* (search for 'tpoff' in elf32-xtensa.c in BFD):
* offset = address - tls_section_vma + align_up(TCB_SIZE, tls_section_alignment)
* where TCB_SIZE is hardcoded to 8. There doesn't seem to be a way to propagate
* the section alignment value from the ld script into the code, so it is hardcoded
* in both places.
* where TCB_SIZE is hardcoded to 8.
* Note this is slightly different compared to the RISC-V port, where offset = address - tls_section_vma.
*/
const uint32_t tls_section_alignment = 0x10; /* has to be in sync with ALIGN value of .flash.rodata section */
const uint32_t tls_section_alignment = (uint32_t) &_flash_rodata_align; /* ALIGN value of .flash.rodata section */
const uint32_t tcb_size = 8; /* Unrelated to FreeRTOS, this is the constant from BFD */
const uint32_t base = (tcb_size + tls_section_alignment - 1) & (~(tls_section_alignment - 1));
*threadptr = (uint32_t)task_thread_local_start - ((uint32_t)&_thread_local_start - (uint32_t)&_rodata_start) - base;
*threadptr = (uint32_t)task_thread_local_start - ((uint32_t)&_thread_local_start - (uint32_t)&_flash_rodata_start) - base;
#if XCHAL_CP_NUM > 0
/* Init the coprocessor save area (see xtensa_context.h) */