Add an option (compiled out by default)

to profile outoing packets for a number of mbuf chain
related parameters
e.g. number of mbufs, wasted space.
probably will do with further work later.

Reviewed by: various
This commit is contained in:
Julian Elischer 2008-04-29 21:23:21 +00:00
parent bcf5b9fa38
commit 6eeac1d921
5 changed files with 168 additions and 0 deletions

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@ -868,7 +868,12 @@ options TCPDEBUG
# The MBUF_STRESS_TEST option enables options which create
# various random failures / extreme cases related to mbuf
# functions. See mbuf(9) for a list of available test cases.
# MBUF_PROFILING enables code to profile teh mbif chains
# exiting the system (via participating interfaces) and
# return a logarithmic histogram of monitored parameters
# (e.g. packet size, wasted space, number of mbufs in chain).
options MBUF_STRESS_TEST
options MBUF_PROFILING
# Statically Link in accept filters
options ACCEPT_FILTER_DATA

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@ -388,6 +388,7 @@ LIBMBPOOL
LIBMCHAIN
LIBALIAS
MBUF_STRESS_TEST
MBUF_PROFILING
NCP
NETATALK opt_atalk.h
PPP_BSDCOMP opt_ppp.h

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@ -35,6 +35,7 @@ __FBSDID("$FreeBSD$");
#include "opt_mac.h"
#include "opt_param.h"
#include "opt_mbuf_stress_test.h"
#include "opt_mbuf_profiling.h"
#include <sys/param.h>
#include <sys/systm.h>
@ -1938,3 +1939,154 @@ m_unshare(struct mbuf *m0, int how)
}
return (m0);
}
#ifdef MBUF_PROFILING
#define MP_BUCKETS 32 /* don't just change this as things may overflow.*/
struct mbufprofile {
u_int64_t wasted[MP_BUCKETS];
u_int64_t used[MP_BUCKETS];
u_int64_t segments[MP_BUCKETS];
} mbprof;
#define MP_MAXDIGITS 21 /* strlen("16,000,000,000,000,000,000") == 21 */
#define MP_NUMLINES 6
#define MP_NUMSPERLINE 16
#define MP_EXTRABYTES 64 /* > strlen("used:\nwasted:\nsegments:\n") */
/* work out max space needed and add a bit of spare space too */
#define MP_MAXLINE ((MP_MAXDIGITS+1) * MP_NUMSPERLINE)
#define MP_BUFSIZE ((MP_MAXLINE * MP_NUMLINES) + 1 + MP_EXTRABYTES)
char mbprofbuf[MP_BUFSIZE];
void
m_profile(struct mbuf *m)
{
int segments = 0;
int used = 0;
int wasted = 0;
while (m) {
segments++;
used += m->m_len;
if (m->m_flags & M_EXT) {
wasted += MHLEN - sizeof(m->m_ext) +
m->m_ext.ext_size - m->m_len;
} else {
if (m->m_flags & M_PKTHDR)
wasted += MHLEN - m->m_len;
else
wasted += MLEN - m->m_len;
}
m = m->m_next;
}
/* be paranoid.. it helps */
if (segments > MP_BUCKETS - 1)
segments = MP_BUCKETS - 1;
if (used > 100000)
used = 100000;
if (wasted > 100000)
wasted = 100000;
/* store in the appropriate bucket */
/* don't bother locking. if it's slightly off, so what? */
mbprof.segments[segments]++;
mbprof.used[fls(used)]++;
mbprof.wasted[fls(wasted)]++;
}
static void
mbprof_textify(void)
{
int offset;
char *c;
u_int64_t *p;
p = &mbprof.wasted[0];
c = mbprofbuf;
offset = snprintf(c, MP_MAXLINE + 10,
"wasted:\n"
"%lld %lld %lld %lld %lld %lld %lld %lld "
"%lld %lld %lld %lld %lld %lld %lld %lld\n",
p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]);
#ifdef BIG_ARRAY
p = &mbprof.wasted[16];
c += offset;
offset = snprintf(c, MP_MAXLINE,
"%lld %lld %lld %lld %lld %lld %lld %lld "
"%lld %lld %lld %lld %lld %lld %lld %lld\n",
p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]);
#endif
p = &mbprof.used[0];
c += offset;
offset = snprintf(c, MP_MAXLINE + 10,
"used:\n"
"%lld %lld %lld %lld %lld %lld %lld %lld "
"%lld %lld %lld %lld %lld %lld %lld %lld\n",
p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]);
#ifdef BIG_ARRAY
p = &mbprof.used[16];
c += offset;
offset = snprintf(c, MP_MAXLINE,
"%lld %lld %lld %lld %lld %lld %lld %lld "
"%lld %lld %lld %lld %lld %lld %lld %lld\n",
p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]);
#endif
p = &mbprof.segments[0];
c += offset;
offset = snprintf(c, MP_MAXLINE + 10,
"segments:\n"
"%lld %lld %lld %lld %lld %lld %lld %lld "
"%lld %lld %lld %lld %lld %lld %lld %lld\n",
p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]);
#ifdef BIG_ARRAY
p = &mbprof.segments[16];
c += offset;
offset = snprintf(c, MP_MAXLINE,
"%lld %lld %lld %lld %lld %lld %lld %lld "
"%lld %lld %lld %lld %lld %lld %lld %lld\n",
p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]);
#endif
}
static int
mbprof_handler(SYSCTL_HANDLER_ARGS)
{
int error;
mbprof_textify();
error = SYSCTL_OUT(req, mbprofbuf, strlen(mbprofbuf) + 1);
return (error);
}
static int
mbprof_clr_handler(SYSCTL_HANDLER_ARGS)
{
int clear, error;
clear = 0;
error = sysctl_handle_int(oidp, &clear, 0, req);
if (error || !req->newptr)
return (error);
if (clear) {
bzero(&mbprof, sizeof(mbprof));
}
return (error);
}
SYSCTL_PROC(_kern_ipc, OID_AUTO, mbufprofile, CTLTYPE_STRING|CTLFLAG_RD,
NULL, 0, mbprof_handler, "A", "mbuf profiling statistics");
SYSCTL_PROC(_kern_ipc, OID_AUTO, mbufprofileclr, CTLTYPE_INT|CTLFLAG_RW,
NULL, 0, mbprof_clr_handler, "I", "clear mbuf profiling statistics");
#endif

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@ -37,6 +37,7 @@
#include "opt_mac.h"
#include "opt_netgraph.h"
#include "opt_carp.h"
#include "opt_mbuf_profiling.h"
#include <sys/param.h>
#include <sys/systm.h>
@ -162,6 +163,7 @@ ether_output(struct ifnet *ifp, struct mbuf *m,
senderr(error);
#endif
M_PROFILE(m);
if (ifp->if_flags & IFF_MONITOR)
senderr(ENETDOWN);
if (!((ifp->if_flags & IFF_UP) &&

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@ -959,4 +959,12 @@ m_tag_find(struct mbuf *m, int type, struct m_tag *start)
#endif /* _KERNEL */
#ifdef MBUF_PROFILING
void m_profile(struct mbuf *m);
#define M_PROFILE(m) m_profile(m)
#else
#define M_PROFILE(m)
#endif
#endif /* !_SYS_MBUF_H_ */