diff options
| author | markm <markm@FreeBSD.org> | 2015-08-22 12:59:05 +0000 |
|---|---|---|
| committer | markm <markm@FreeBSD.org> | 2015-08-22 12:59:05 +0000 |
| commit | 8982309189722bc5e7c572ea0581f714bf1c6337 (patch) | |
| tree | 52609275855ad29d2bfae105777e35ddecf436a1 /sys/conf | |
| parent | 47e7b3851fdc5ab885ee92247dc2599932a7b7d8 (diff) | |
| download | FreeBSD-src-8982309189722bc5e7c572ea0581f714bf1c6337.zip FreeBSD-src-8982309189722bc5e7c572ea0581f714bf1c6337.tar.gz | |
Make the UMA harvesting go away completely if not wanted. Default to "not wanted".
Provide and document the RANDOM_ENABLE_UMA option.
Change RANDOM_FAST to RANDOM_UMA to clarify the harvesting.
Remove RANDOM_DEBUG option, replace with SDT probes. These will be of
use to folks measuring the harvesting effect when deciding whether to
use RANDOM_ENABLE_UMA.
Requested by: scottl and others.
Approved by: so (/dev/random blanket)
Differential Revision: https://reviews.freebsd.org/D3197
Diffstat (limited to 'sys/conf')
| -rw-r--r-- | sys/conf/NOTES | 6 | ||||
| -rw-r--r-- | sys/conf/options | 9 |
2 files changed, 8 insertions, 7 deletions
diff --git a/sys/conf/NOTES b/sys/conf/NOTES index 7bc2048..05ffe55 100644 --- a/sys/conf/NOTES +++ b/sys/conf/NOTES @@ -2985,8 +2985,10 @@ options MAXFILES=999 #options RANDOM_YARROW # Yarrow CSPRNG (old default) #options RANDOM_LOADABLE # Allow the algorithm to be loaded as # a module. -# For developers. -options RANDOM_DEBUG # Extra debugging messages +# Select this to allow high-rate but potentially expensive +# harvesting of Slab-Allocator entropy. In very high-rate +# situations the value of doing this is dubious at best. +options RANDOM_ENABLE_UMA # slab allocator # Module to enable execution of application via emulators like QEMU options IMAGACT_BINMISC diff --git a/sys/conf/options b/sys/conf/options index 089b1a2..936abc9 100644 --- a/sys/conf/options +++ b/sys/conf/options @@ -945,17 +945,16 @@ RACCT_DEFAULT_TO_DISABLED opt_global.h RCTL opt_global.h # Random number generator(s) -# The DEBUG option is in global.h as the random harvesting -# puts probes all over the place, and it makes little sense -# to pollute these headers with an extra include. -RANDOM_DEBUG opt_random.h -# Which CSPRNG hashes we get. +# Which CSPRNG hash we get. # If Yarrow is not chosen, Fortuna is selected. RANDOM_YARROW opt_random.h # With this, no entropy processor is loaded, but the entropy # harvesting infrastructure is present. This means an entropy # processor may be loaded as a module. RANDOM_LOADABLE opt_random.h +# This turns on high-rate and potentially expensive harvesting in +# the uma slab allocator. +RANDOM_ENABLE_UMA opt_global.h # Intel em(4) driver EM_MULTIQUEUE opt_em.h |
