x86: vdso: Compute timens page offset staticallyHEADmaster

The expression `((void *)&__timens_vdso_data - (void *)&__vdso_data)`
seems harmless, but it actually results in quite a bit of code and two
jumps, in a place that's supposed to be somewhat lean on code. The value
of that calculation is always 3*PAGE_SIZE, as it turns out. Changing it
to that results in a more modest cmov instruction being emitted. It also
makes it a bit more clear what's happening.

To accomplish this, define offset macros in vvar.h, which can be shared
by C code and by the linker script that decides where these pages will
actually go.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

0 files changed, 0 insertions, 0 deletions