[PW_SID:993002] [v3] riscv: Add sysctl to control discard of vstate on syscall entry - #801
[PW_SID:993002] [v3] riscv: Add sysctl to control discard of vstate on syscall entry#801linux-riscv-bot wants to merge 1 commit into
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Vector registers are always clobbered in the syscall entry path to enforce the documented ABI that vector state is not preserved across syscalls. However, this operation can be slow on some RISC-V cores. To mitigate this performance impact, add a sysctl knob to control whether vector state is discarded in the syscall entry path: /proc/sys/abi/riscv_v_vstate_discard Valid values are: 0: Vector state is not intentionally clobbered when entering a syscall 1: Vector state is always clobbered when entering a syscall The initial state is controlled by CONFIG_RISCV_ISA_V_VSTATE_DISCARD. Fixes: 9657e9b ("riscv: Discard vector state on syscalls") Signed-off-by: Drew Fustini <dfustini@tenstorrent.com> Signed-off-by: Linux RISC-V bot <linux.riscv.bot@gmail.com>
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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Patch 1: "[v3] riscv: Add sysctl to control discard of vstate on syscall entry" |
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PR for series 993002 applied to workflow__riscv__fixes
Name: [v3] riscv: Add sysctl to control discard of vstate on syscall entry
URL: https://patchwork.kernel.org/project/linux-riscv/list/?series=993002
Version: 3