arch/riscv/vector.rst

13 Two new prctl() calls are added to allow programs to manage the enablement
26     Sets the Vector enablement status of the calling thread, where the control
27     argument consists of two 2-bit enablement statuses and a bit for inheritance
30     Enablement status is a tri-state value each occupying 2-bit of space in
34       enablement status on execve(). The system-wide default setting can be
49     enablement status of current thread, and the setting at bit[3:2] takes place
54           Vector enablement status for the calling thread. The calling thread is
57           but the current enablement status is not off. Setting
59           the original enablement status.
62           Vector enablement setting for the calling thread at the next execve()
64           then the enablement status will be decided by the system-wide
65           enablement status when execve() happen.
75         * EINVAL: Vector not supported, invalid enablement status for current or
82           immediately. The enablement status specified in
91     Gets the same Vector enablement status for the calling thread. Setting for
107 developers to control the default Vector enablement status for userspace
113     system enablement status for new starting userspace programs. Valid values
119     Reading this file returns the current system default enablement status.
121     At every execve() call, a new enablement status of the new process is set to
131     Modifying the system default enablement status does not affect the enablement