Commit Graph

17 Commits

Author SHA1 Message Date
Bosko Milekic
099a0e588c Bring in mbuma to replace mballoc.
mbuma is an Mbuf & Cluster allocator built on top of a number of
extensions to the UMA framework, all included herein.

Extensions to UMA worth noting:
  - Better layering between slab <-> zone caches; introduce
    Keg structure which splits off slab cache away from the
    zone structure and allows multiple zones to be stacked
    on top of a single Keg (single type of slab cache);
    perhaps we should look into defining a subset API on
    top of the Keg for special use by malloc(9),
    for example.
  - UMA_ZONE_REFCNT zones can now be added, and reference
    counters automagically allocated for them within the end
    of the associated slab structures.  uma_find_refcnt()
    does a kextract to fetch the slab struct reference from
    the underlying page, and lookup the corresponding refcnt.

mbuma things worth noting:
  - integrates mbuf & cluster allocations with extended UMA
    and provides caches for commonly-allocated items; defines
    several zones (two primary, one secondary) and two kegs.
  - change up certain code paths that always used to do:
    m_get() + m_clget() to instead just use m_getcl() and
    try to take advantage of the newly defined secondary
    Packet zone.
  - netstat(1) and systat(1) quickly hacked up to do basic
    stat reporting but additional stats work needs to be
    done once some other details within UMA have been taken
    care of and it becomes clearer to how stats will work
    within the modified framework.

From the user perspective, one implication is that the
NMBCLUSTERS compile-time option is no longer used.  The
maximum number of clusters is still capped off according
to maxusers, but it can be made unlimited by setting
the kern.ipc.nmbclusters boot-time tunable to zero.
Work should be done to write an appropriate sysctl
handler allowing dynamic tuning of kern.ipc.nmbclusters
at runtime.

Additional things worth noting/known issues (READ):
   - One report of 'ips' (ServeRAID) driver acting really
     slow in conjunction with mbuma.  Need more data.
     Latest report is that ips is equally sucking with
     and without mbuma.
   - Giant leak in NFS code sometimes occurs, can't
     reproduce but currently analyzing; brueffer is
     able to reproduce but THIS IS NOT an mbuma-specific
     problem and currently occurs even WITHOUT mbuma.
   - Issues in network locking: there is at least one
     code path in the rip code where one or more locks
     are acquired and we end up in m_prepend() with
     M_WAITOK, which causes WITNESS to whine from within
     UMA.  Current temporary solution: force all UMA
     allocations to be M_NOWAIT from within UMA for now
     to avoid deadlocks unless WITNESS is defined and we
     can determine with certainty that we're not holding
     any locks when we're M_WAITOK.
   - I've seen at least one weird socketbuffer empty-but-
     mbuf-still-attached panic.  I don't believe this
     to be related to mbuma but please keep your eyes
     open, turn on debugging, and capture crash dumps.

This change removes more code than it adds.

A paper is available detailing the change and considering
various performance issues, it was presented at BSDCan2004:
http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf
Please read the paper for Future Work and implementation
details, as well as credits.

Testing and Debugging:
    rwatson,
    brueffer,
    Ketrien I. Saihr-Kesenchedra,
    ...
Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
Mark Murray
9ff712b0f5 WARNS=2 fixes with NO_WERROR set, as there are some header issues
with namelists. use __FBSDID().
2001-12-12 00:13:37 +00:00
Bosko Milekic
70a61707f6 Re-enable mbtypes statistics in the mbuf allocator. I disabled these
when I changed the allocator bits. This implements per-CPU mbtypes
stats by keeping net number of decrements/increments of a given mbtype
per-CPU and then summing all of the per-CPU mbtypes to produce the total
net number of allocated mbufs of the given mbtype.
Counters are carefully balanced to avoid/prevent underflows/overflows.

mbtypes stats are re-enabled with the idea that we may occasionally
(although very rarely) observe slight inconsistencies in the stat
reporting. Most of the time, we should be fine, though.

Also make appropriate modifications to netstat(1) and systat(1) to do
the necessary reporting.

Submitted by: Jiangyi Liu <jyliu@163.net>
2001-09-30 01:58:39 +00:00
Bosko Milekic
49f854f926 - Do not handle the per-CPU containers in mbuf code as though the cpuids
were indices in a dense array. The cpuids are a sparse set and treat
  them as such, setting up containers only for CPUs activated during
  mb_init().

- Fix netstat(1) and systat(1) to treat the per-CPU stats area as a sparse
  map, in accordance with the above.

This allows us to properly boot with certain CPUs disactivated. However, if
we later decide to re-activate said CPUs, we will barf until we decide to
implement CPU spinon/spinoff callback hooks to allow for said CPUs' per-CPU
containers to get configured on their activation.

Reported by: mjacob
Partially (sys/ diffs) Submitted by: mjacob
2001-07-26 18:47:46 +00:00
Bosko Milekic
4edec6b79a Make sure to try hw.ncpu if kern.smp.cpus doesn't exist (i.e. on UP) when
getting number of CPUs.
2001-06-23 17:03:27 +00:00
Bosko Milekic
08442f8a82 Introduce numerous SMP friendly changes to the mbuf allocator. Namely,
introduce a modified allocation mechanism for mbufs and mbuf clusters; one
which can scale under SMP and which offers the possibility of resource
reclamation to be implemented in the future. Notable advantages:

 o Reduce contention for SMP by offering per-CPU pools and locks.
 o Better use of data cache due to per-CPU pools.
 o Much less code cache pollution due to excessively large allocation macros.
 o Framework for `grouping' objects from same page together so as to be able
   to possibly free wired-down pages back to the system if they are no longer
   needed by the network stacks.

 Additional things changed with this addition:

  - Moved some mbuf specific declarations and initializations from
    sys/conf/param.c into mbuf-specific code where they belong.
  - m_getclr() has been renamed to m_get_clrd() because the old name is really
    confusing. m_getclr() HAS been preserved though and is defined to the new
    name. No tree sweep has been done "to change the interface," as the old
    name will continue to be supported and is not depracated. The change was
    merely done because m_getclr() sounds too much like "m_get a cluster."
  - TEMPORARILY disabled mbtypes statistics displaying in netstat(1) and
    systat(1) (see TODO below).
  - Fixed systat(1) to display number of "free mbufs" based on new per-CPU
    stat structures.
  - Fixed netstat(1) to display new per-CPU stats based on sysctl-exported
    per-CPU stat structures. All infos are fetched via sysctl.

 TODO (in order of priority):

  - Re-enable mbtypes statistics in both netstat(1) and systat(1) after
    introducing an SMP friendly way to collect the mbtypes stats under the
    already introduced per-CPU locks (i.e. hopefully don't use atomic() - it
    seems too costly for a mere stat update, especially when other locks are
    already present).
  - Optionally have systat(1) display not only "total free mbufs" but also
    "total free mbufs per CPU pool."
  - Fix minor length-fetching issues in netstat(1) related to recently
    re-enabled option to read mbuf stats from a core file.
  - Move reference counters at least for mbuf clusters into an unused portion
    of the cluster itself, to save space and need to allocate a counter.
  - Look into introducing resource freeing possibly from a kproc.

Reviewed by (in parts): jlemon, jake, silby, terry
Tested by: jlemon (Intel & Alpha), mjacob (Intel & Alpha)
Preliminary performance measurements: jlemon (and me, obviously)
URL: http://people.freebsd.org/~bmilekic/mb_alloc/
2001-06-22 06:35:32 +00:00
Alfred Perlstein
2873654a65 Fix systat to use the kern.ipc.mbtypes sysctl instead of referencing a
structure member that doesn't exist anymore.
Use getsysctlbyname for kern.ipc.mbstat instead of sysctl.
Use netstat's method of displaying values from mtnames.

Submitted by: Ian Dowse <iedowse@maths.tcd.ie>
Missed by PR: 19809
2000-07-15 16:24:21 +00:00
Peter Wemm
3879bee426 systat is way too comfortable with curses internals... 1999-08-30 08:18:09 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
David E. O'Brien
d22889b821 Quiet many compiler warnings. 1998-10-08 09:56:10 +00:00
Warner Losh
448b84a0e4 o Use snprintf rather than sprintf
o Add more checks for buffer overflows
o Use snprintf rather than strcat/cpy and have better checks for max
  length exceeded.

Most of these changes are not exploitable buffer overruns, but it never
hurts to be safe.

Inspired by and obtained from: OpenBSD
1998-06-09 04:17:29 +00:00
Garrett Wollman
03e00a72c6 Add a mode to display ICMP statistics.
Inspired by:	IRIX netstat -C
1997-09-24 02:43:45 +00:00
Garrett Wollman
646bbae242 Use new sysctl(3) interface to mbuf statistics. While we're at it,
count free mbufs correctly.
1997-02-24 20:59:03 +00:00
John Polstra
a49b055f5c Fix a bug in the mbufs display, seen when there was a large number
of mbufs in use.  If the number reached, e.g., 4 digits, then later
decreased to 3 digits, the last digit of the 4-digit number was
not erased.  This caused the display to show a wildly high number of
mbufs in use.
1996-05-27 17:47:09 +00:00
Rodney W. Grimes
7799f52a32 Remove trailing whitespace. 1995-05-30 06:41:30 +00:00
Garrett Wollman
4be4929c2b Get rid of _PATH_UNIX completely; use getbootfile(3) instead.
DANGER WILL ROBINSON!
_PATH_UNIX is currently defined as the literal string "don't use this".
I am of two minds about this myself, but wanted to get something into the
tree as quickly as possible.
1994-09-24 00:08:43 +00:00
Rodney W. Grimes
9b50d90275 BSD 4.4 Lite Usr.bin Sources 1994-05-27 12:33:43 +00:00