From 1b82e02f4d91dc0942e754fa6c08042537f13980 Mon Sep 17 00:00:00 2001 From: Alan Somers Date: Mon, 23 May 2016 20:29:18 +0000 Subject: Add bit_count to the bitstring(3) api Add a bit_count function, which efficiently counts the number of bits set in a bitstring. sys/sys/bitstring.h tests/sys/sys/bitstring_test.c share/man/man3/bitstring.3 Add bit_alloc sys/kern/subr_unit.c Use bit_count instead of a naive counting loop in check_unrhdr, used when INVARIANTS are enabled. The userland test runs about 6x faster in a generic build, or 8.5x faster when built for Nehalem, which has the POPCNT instruction. sys/sys/param.h Bump __FreeBSD_version due to the addition of bit_alloc UPDATING Add a note about the ABI incompatibility of the bitstring(3) changes, as suggested by lidl. Suggested by: gibbs Reviewed by: gibbs, ngie MFC after: 9 days X-MFC-With: 299090, 300538 Relnotes: yes Sponsored by: Spectra Logic Corp Differential Revision: https://reviews.freebsd.org/D6255 --- UPDATING | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'UPDATING') diff --git a/UPDATING b/UPDATING index fd47ac042b799..df0542dfab3c6 100644 --- a/UPDATING +++ b/UPDATING @@ -31,6 +31,12 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 11.x IS SLOW: disable the most expensive debugging functionality run "ln -s 'abort:false,junk:false' /etc/malloc.conf".) +20160523: + The bitstring(3) API has been updated with new functionality and + improved performance. But it is binary-incompatible with the old API. + Objects built with the new headers may not be linked against objects + built with the old headers. + 20160520: The brk and sbrk functions have been removed from libc on arm64. Binutils from ports has been updated to not link to these -- cgit v1.2.3