Don't dump entries that were modified during the time the KTR buffer was being

copied to userspace. Failing to do this would result in entries at the bottom
of the ktrdump output to be more recent than entries at the top.

With this change the timestamps are monotonically decreasing going from the
top to the bottom of the ktrdump output.
This commit is contained in:
Neel Natu 2014-03-14 22:07:08 +00:00
parent 61346cbdc7
commit 3447a66db8
1 changed files with 11 additions and 3 deletions

View File

@ -93,7 +93,7 @@ main(int ac, char **av)
char *p;
int version;
int entries;
int index;
int index, index2;
int parm;
int in;
int c;
@ -182,7 +182,8 @@ main(int ac, char **av)
if (kvm_read(kd, nl[2].n_value, &index, sizeof(index)) == -1 ||
kvm_read(kd, nl[3].n_value, &bufptr,
sizeof(bufptr)) == -1 ||
kvm_read(kd, bufptr, buf, sizeof(*buf) * entries) == -1)
kvm_read(kd, bufptr, buf, sizeof(*buf) * entries) == -1 ||
kvm_read(kd, nl[2].n_value, &index2, sizeof(index2)) == -1)
errx(1, "%s", kvm_geterr(kd));
}
@ -289,7 +290,14 @@ next: if ((c = *p++) == '\0')
parms[4], parms[5]);
fprintf(out, "\n");
if (!iflag) {
if (i == index)
/*
* 'index' and 'index2' are the values of 'ktr_idx'
* before and after the KTR buffer was copied into
* 'buf'. Since the KTR entries between 'index' and
* 'index2' were in flux while the KTR buffer was
* being copied to userspace we don't dump them.
*/
if (i == index2)
break;
if (--i < 0)
i = entries - 1;