Nicolas Pitre 00a9634c05 riscv: new TLS-based arch_is_user_context() implementation ... This reverts the bulk of commit c8bfc2afda ("riscv: make arch_is_user_context() SMP compatible") and replaces it with a flag stored in the thread local storage (TLS) area, therefore making TLS mandatory for userspace support on RISC-V. This has many advantages: - The tp (x4) register is already dedicated by the standard for this purpose, making TLS support almost free. - This is very efficient, requiring only a single instruction to clear and 2 instructions to set. - This makes the SMP case much more efficient. No need for funky exception code any longer. - SMP and non-SMP now use the same implementation making maintenance easier. - The is_user_mode variable no longer requires a dedicated PMP mapping and therefore freeing one PMP slot for other purposes. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> 5f65dbcc9dab3d39473b05397e05.		2022-06-23 13:12:05 -04:00
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kernel_arch_data.h	arch: migrate includes to <zephyr/...>	2022-05-06 19:57:22 +02:00
kernel_arch_func.h	riscv: new TLS-based arch_is_user_context() implementation	2022-06-23 13:12:05 -04:00
offsets_short_arch.h	riscv: implement arch_switch()	2022-03-21 07:28:05 -04:00
pmp.h	riscv: pmp: add new usermode support	2022-04-29 15:30:00 +02:00