Jim Huang
Jim Huang
When tickless scheduling is enabled, kernel timer varies once SysTick gets reload value from wakeup state. The proper kernel timer compensation is required to fix up the timing though.
After commit 27b9fb2d41905266a85d4d0776862cc1816eed81, F9 microkernel has FPU support now. However, it brings a side effect of abnormal statistics as the following: ``` -------TOP------ 4209 [ schedule_select ] 1548 [ softirq_execute...
Function `test_and_set_word` and `test_and_set_bit` in file platform/bitops.c implements the basic locking mechanism utilizing `ldrex` and `strexeq` instruction. However, other similar routines are not taken into consideration carefully, and we have...
Since the book "Understanding Computation" always mentions `>>` prompt for Ruby's interactive console, it should be more precise to take option `--simple-prompt`.
Piko/RT depends on several string routines such as `memcpy` and `memset`. They can be optimized in Thumb2 assembly in consideration of performance and/or size. Sample implementation for `memcpy`: ```C static...
It would be great if we can provide some high level descriptions about the supported opcodes/features in our JVM implementation. See the following for reference: * https://github.com/JorthVM/JorthVM/blob/master/implementation.md * https://github.com/TheCurle/Purpuri/blob/master/docs/docs/spec.md
After the completion of function 'read_startup_ri_file', a trailing newline character was written into the terminal. Therefore, there was obviously a blank line between the original 1-2-3 help message and our...
Use `make check` to reproduce. Reported by `dmesg`: ``` Bad or missing usercopy whitelist? Kernel memory exposure attempt detected from SLUB object 'simplefs_cache' (offset 4, size 4)! Call Trace: __check_heap_object+0xb7/0x120...
`map.[ch]` is the C Implementation for C++ std::map using red-black tree. It works well, but there is room for improvements. We can take some tricks used in [Red-black Trees in...
With the ability to record and print histograms, we can observe instruction frequency and print. Sample output: ``` instruction usage histogram ~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1. lw 16.37% [843055543] ####################################### 2. xor 13.85%...