Date: Sun, 28 Nov 2010 18:59:53 +0000 (UTC) From: Colin Percival <cperciva@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-8@freebsd.org Subject: svn commit: r216015 - stable/8/sys/kern Message-ID: <201011281859.oASIxrgv039261@svn.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: cperciva Date: Sun Nov 28 18:59:52 2010 New Revision: 216015 URL: http://svn.freebsd.org/changeset/base/216015 Log: MFC r215665,r215732: Don't lose seconds to integer overflow if we go more than one second between calls to tc_windup. Modified: stable/8/sys/kern/kern_tc.c Directory Properties: stable/8/sys/ (props changed) stable/8/sys/amd64/include/xen/ (props changed) stable/8/sys/cddl/contrib/opensolaris/ (props changed) stable/8/sys/contrib/dev/acpica/ (props changed) stable/8/sys/contrib/pf/ (props changed) Modified: stable/8/sys/kern/kern_tc.c ============================================================================== --- stable/8/sys/kern/kern_tc.c Sun Nov 28 18:53:57 2010 (r216014) +++ stable/8/sys/kern/kern_tc.c Sun Nov 28 18:59:52 2010 (r216015) @@ -440,6 +440,16 @@ tc_windup(void) ncount = 0; th->th_offset_count += delta; th->th_offset_count &= th->th_counter->tc_counter_mask; + while (delta > th->th_counter->tc_frequency) { + /* Eat complete unadjusted seconds. */ + delta -= th->th_counter->tc_frequency; + th->th_offset.sec++; + } + if ((delta > th->th_counter->tc_frequency / 2) && + (th->th_scale * delta < ((uint64_t)1 << 63))) { + /* The product th_scale * delta just barely overflows. */ + th->th_offset.sec++; + } bintime_addx(&th->th_offset, th->th_scale * delta); /*
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201011281859.oASIxrgv039261>