Optimize _sbrk_r when no increment is needed#14
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SilentButeo2 wants to merge 1 commit intoDRNadler:masterfrom
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Optimize _sbrk_r when no increment is needed#14SilentButeo2 wants to merge 1 commit intoDRNadler:masterfrom
SilentButeo2 wants to merge 1 commit intoDRNadler:masterfrom
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DRNadler
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Oct 15, 2023
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Thanks! Some questions though:
- How often is mallinfo called? Is this really worth adding code to optimize?
- If so, please add a comment about WHY this is worthwhile optimizing ie Happens when called from mallinfo twice per week
- Didn't you mean to cast the return value to (void*), not (char*)?
Thanks again,
Best Regards, Dave
I do not know why
I think I am not sure if this optimization is needed but it seems cheap with only a few lines added.
All returns in |
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During debug I hit the _sbrk_r() function, but the incr parameter was 0. Callstack points out it is mallinfo() that initiates the call.
Because the current code goes into a critical section (ST) or suspends all tasks (NXP) but doesn't change anything in between, this is optimized away.
Unless the _sbrk_r is also used do some limit checks, I think this adjustment is safe.
Tested with an ST setup.