lock probably needs some kind of barrier
#3
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Done. We have added a compiler barrier. |
japaric
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andrewgazelka
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drop compiler-builtins dependency, add documentation
andrewgazelka
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When I currently request GDB to dump a hard fault stack, I see
something like this:
(gdb) bt
#0 UserHardFault_ (ef=0x10001fb8) at /depots/cortex-m-rt/src/lib.rs:537
rtic-rs#1 0x08003fe6 in HardFault ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
GDB can't unwind past HardFault since the current implementation of
this function overwrites the Link Register (LR) value. This change
pushes LR and R0 (to maintain 8-byte stack alignment) to the stack
before transferring execution to UserHardFault().
After this change, I see a callstack like this from GDB:
(gdb) bt
#0 UserHardFault_ (ef=0x10001fb0) at /depots/cortex-m-rt/src/lib.rs:537
rtic-rs#1 0x08003fe8 in HardFault ()
rtic-rs#2 <signal handler called>
rtic-rs#3 0x08002820 in core::ptr::read_volatile (src=0x48001800) at libcore/ptr.rs:472
rtic-rs#4 0x080001a2 in main () at src/07-registers/src/main.rs:14
Notes:
* This code uses 8 more stack bytes.
* Increases the size of the HardFault handler by 2 narrow instructions
or 4 bytes. This could be decreased to 2 bytes by removing the pop
since UserHardFault() doesn't currently return but it just looks too
odd for me to do as an initial attempt.
andrewgazelka
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131: Allow GDB to unwind HardFault callstacks r=therealprof a=adamgreen When I currently request GDB to dump a hard fault stack, I see something like this: ``` (gdb) bt #0 UserHardFault_ (ef=0x10001fb8) at /depots/cortex-m-rt/src/lib.rs:537 rtic-rs#1 0x08003fe6 in HardFault () Backtrace stopped: previous frame identical to this frame (corrupt stack?) ``` GDB can't unwind past HardFault since the current implementation of this function overwrites the Link Register (LR) value. This change pushes LR and R0 (to maintain 8-byte stack alignment) to the stack before transferring execution to UserHardFault(). After this change, I see a callstack like this from GDB: ``` (gdb) bt #0 UserHardFault_ (ef=0x10001fb0) at /depots/cortex-m-rt/src/lib.rs:537 rtic-rs#1 0x08003fe8 in HardFault () rtic-rs#2 <signal handler called> rtic-rs#3 0x08002820 in core::ptr::read_volatile (src=0x48001800) at libcore/ptr.rs:472 rtic-rs#4 0x080001a2 in main () at src/07-registers/src/main.rs:14 ``` Notes: * This code uses 8 more stack bytes. * Increases the size of the HardFault handler by 2 narrow instructions or 4 bytes. This could be decreased to 2 bytes by removing the pop since UserHardFault() doesn't currently return but it just looks too odd for me to do as an initial attempt. Co-authored-by: Adam Green <adamgreen@users.noreply.github.com>
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Either a compiler, memory or an instruction one or a mixture of them. To prevent the closure code from being executed outside the modified BASEPRI context. This should become more apparent when dealing with non-volatile resources (i.e. not peripherals)
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