On Wed, Jun 25, 2025 at 05:12:20PM +0100, Colin Ian King wrote: > Analysis with gcov while running the stress-ng urandom stressor > shows that there are a couple of fortify panic paths that are highly > unlikely to be executed for well-behaving code. Adding appropriate > branch hints improves the stress-ng urandom stressor my a small > but statistically measureable amount. Ran 100 x 1 minute tests and > measured the stressor bogo-op rates on a Debian based Intel(R) > Core(TM) Ultra 9 285K with a 6.15 kernel with turbo disabled to > reduce jitter. > > Results based on a Geometic Mean of 100 tests: > > Without patch: 50512.95 bogo-ops/sec > With patch: 50819.58 bogo-ops/sec > > %Std.Deviation of ~0.18%, so low jitter in results, improvement of ~0.6% > > Signed-off-by: Colin Ian King <colin.i.king@xxxxxxxxx> Nice find! It seems some ftrace configs are unhappy with this change, though? -Kees -- Kees Cook
