On 30.08.2013 00:58, Navdeep Parhar wrote:
I'd like to merge r254342 from user/np/cxl_tuning to head if there are
no objections.
I don't object in principle, though I'm wonder whether we should
have a more generic way of passing this kind of flags to the allocator?
We probably get more demands for special allocations or variants in
the future. And now would be the time as it is still in its infancy
and we can easily adjust all consumers before it becomes widespread.
See more comments inline.
http://svnweb.freebsd.org/base/user/np/cxl_tuning/sys/kern/kern_mbuf.c?r1=254334&r2=254342&diff_format=u
http://svnweb.freebsd.org/base/user/np/cxl_tuning/sys/sys/mbuf.h?r1=254334&r2=254342&diff_format=u
---------------------
Perform lazy initialization of a cluster's refcount if possible. This
doesn't change anything for the common cases where the constructor is
given an mbuf to attach to the cluster, or when the cluster is obtained
with m_cljget(NULL, ...) and attached later with m_cljset(). But it
allows for an alternate usage scenario where the cluster is managed
EXT_EXTREF style without ever having to look up its "usual" refcount via
uma_find_refcnt.
---------------------
Regards,
Navdeep
diff -r 9753d3e51363 -r c9388a59fba6 sys/kern/kern_mbuf.c
--- a/sys/kern/kern_mbuf.c Thu Aug 29 11:16:04 2013 -0700
+++ b/sys/kern/kern_mbuf.c Thu Aug 29 11:16:04 2013 -0700
@@ -503,8 +503,6 @@ mb_dtor_pack(void *mem, int size, void *
static int
mb_ctor_clust(void *mem, int size, void *arg, int how)
{
- struct mbuf *m;
- u_int *refcnt;
int type;
uma_zone_t zone;
@@ -535,10 +533,11 @@ mb_ctor_clust(void *mem, int size, void
break;
}
- m = (struct mbuf *)arg;
- refcnt = uma_find_refcnt(zone, mem);
- *refcnt = 1;
- if (m != NULL) {
+ if (arg != NULL) {
+ struct mbuf *m = arg;
+ u_int *refcnt = uma_find_refcnt(zone, mem);
We typically do not declare variables inside {} statements but only
at the top of a function. Also declaration-initialization is not
really permitted by style(9) even though it is used in a few places.
--
Andre
+
+ *refcnt = 1;
m->m_ext.ext_buf = (caddr_t)mem;
m->m_data = m->m_ext.ext_buf;
m->m_flags |= M_EXT;
@@ -549,6 +548,10 @@ mb_ctor_clust(void *mem, int size, void
m->m_ext.ext_type = type;
m->m_ext.ext_flags = 0;
m->m_ext.ref_cnt = refcnt;
+ } else {
+#ifdef INVARIANTS
+ *uma_find_refcnt(zone, mem) = 0;
+#endif
}
return (0);
diff -r 9753d3e51363 -r c9388a59fba6 sys/sys/mbuf.h
--- a/sys/sys/mbuf.h Thu Aug 29 11:16:04 2013 -0700
+++ b/sys/sys/mbuf.h Thu Aug 29 11:16:04 2013 -0700
@@ -721,6 +721,7 @@ m_cljset(struct mbuf *m, void *cl, int t
m->m_ext.ext_type = type;
m->m_ext.ext_flags = 0;
m->m_ext.ref_cnt = uma_find_refcnt(zone, cl);
+ *m->m_ext.ref_cnt = 1;
m->m_flags |= M_EXT;
}
_______________________________________________
freebsd-net@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-net
To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
_______________________________________________
freebsd-net@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-net
To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
