Author: davide
Date: Mon Jul 30 22:46:42 2012
New Revision: 238925
URL: http://svn.freebsd.org/changeset/base/238925
Log:
Until now KTR_ENTRIES, which defines the size of circular buffer used in
ktr(4), was constrained to be a power of two. Remove this constraint and
update sys/conf/NOTES accordingly.
Reviewed by: jhb
Approved by: gnn (mentor)
Sponsored by: Google Summer of Code 2012
Modified:
head/sys/conf/NOTES
head/sys/kern/kern_ktr.c
Modified: head/sys/conf/NOTES
==============================================================================
--- head/sys/conf/NOTES Mon Jul 30 21:58:28 2012 (r238924)
+++ head/sys/conf/NOTES Mon Jul 30 22:46:42 2012 (r238925)
@@ -435,7 +435,7 @@ options KTRACE_REQUEST_POOL=101
#
# KTR is a kernel tracing facility imported from BSD/OS. It is
# enabled with the KTR option. KTR_ENTRIES defines the number of
-# entries in the circular trace buffer; it must be a power of two.
+# entries in the circular trace buffer; it may be an arbitrary number.
# KTR_COMPILE defines the mask of events to compile into the kernel as
# defined by the KTR_* constants in <sys/ktr.h>. KTR_MASK defines the
# initial value of the ktr_mask variable which determines at runtime
Modified: head/sys/kern/kern_ktr.c
==============================================================================
--- head/sys/kern/kern_ktr.c Mon Jul 30 21:58:28 2012 (r238924)
+++ head/sys/kern/kern_ktr.c Mon Jul 30 22:46:42 2012 (r238925)
@@ -283,7 +283,7 @@ ktr_tracepoint(u_int mask, const char *f
{
do {
saveindex = ktr_idx;
- newindex = (saveindex + 1) & (KTR_ENTRIES - 1);
+ newindex = (saveindex + 1) % KTR_ENTRIES;
} while (atomic_cmpset_rel_int(&ktr_idx, saveindex, newindex)
== 0);
entry = &ktr_buf[saveindex];
}
@@ -338,7 +338,7 @@ static int db_mach_vtrace(void);
DB_SHOW_COMMAND(ktr, db_ktr_all)
{
- tstate.cur = (ktr_idx - 1) & (KTR_ENTRIES - 1);
+ tstate.cur = (ktr_idx - 1) % KTR_ENTRIES;
tstate.first = -1;
db_ktr_verbose = 0;
db_ktr_verbose |= (strchr(modif, 'v') != NULL) ? 2 : 0;
_______________________________________________
svn-src-head@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
