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| author | Xi Ruoyao <xry111@xry111.site> | 2025-04-11 10:46:00 +0800 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@dabbelt.com> | 2025-06-05 14:03:09 -0700 |
| commit | ee0d03053e7009a3a3532fb37f6c94bfa0a8cca3 (patch) | |
| tree | 34bf27155e35245602344027be5fb8acb7ced1e7 /arch/riscv/include/asm/vdso/getrandom.h | |
| parent | a869b8c29f864b9530a6473a30c09546333b571a (diff) | |
| download | lwn-ee0d03053e7009a3a3532fb37f6c94bfa0a8cca3.tar.gz lwn-ee0d03053e7009a3a3532fb37f6c94bfa0a8cca3.zip | |
RISC-V: vDSO: Wire up getrandom() vDSO implementation
Hook up the generic vDSO implementation to the generic vDSO getrandom
implementation by providing the required __arch_chacha20_blocks_nostack
and getrandom_syscall implementations. Also wire up the selftests.
The benchmark result:
vdso: 25000000 times in 2.466341333 seconds
libc: 25000000 times in 41.447720005 seconds
syscall: 25000000 times in 41.043926672 seconds
vdso: 25000000 x 256 times in 162.286219353 seconds
libc: 25000000 x 256 times in 2953.855018685 seconds
syscall: 25000000 x 256 times in 2796.268546000 seconds
[ alex: - Fix dynamic relocation
- Squash Nathan's fix https://lore.kernel.org/all/20250423-riscv-fix-compat_vdso-lld-v2-1-b7bbbc244501@kernel.org/
- Add comment from Loongarch ]
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Link: https://lore.kernel.org/r/20250411024600.16045-1-xry111@xry111.site
Tested-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Diffstat (limited to 'arch/riscv/include/asm/vdso/getrandom.h')
| -rw-r--r-- | arch/riscv/include/asm/vdso/getrandom.h | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/vdso/getrandom.h b/arch/riscv/include/asm/vdso/getrandom.h new file mode 100644 index 000000000000..8dc92441702a --- /dev/null +++ b/arch/riscv/include/asm/vdso/getrandom.h @@ -0,0 +1,30 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2025 Xi Ruoyao <xry111@xry111.site>. All Rights Reserved. + */ +#ifndef __ASM_VDSO_GETRANDOM_H +#define __ASM_VDSO_GETRANDOM_H + +#ifndef __ASSEMBLY__ + +#include <asm/unistd.h> + +static __always_inline ssize_t getrandom_syscall(void *_buffer, size_t _len, unsigned int _flags) +{ + register long ret asm("a0"); + register long nr asm("a7") = __NR_getrandom; + register void *buffer asm("a0") = _buffer; + register size_t len asm("a1") = _len; + register unsigned int flags asm("a2") = _flags; + + asm volatile ("ecall\n" + : "+r" (ret) + : "r" (nr), "r" (buffer), "r" (len), "r" (flags) + : "memory"); + + return ret; +} + +#endif /* !__ASSEMBLY__ */ + +#endif /* __ASM_VDSO_GETRANDOM_H */ |