d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
a5c4836d39
freebsd-nq/sys/kern
History
David Malone a5c4836d39 Replace the mbuf external reference counting code with something 
that should be better.

The old code counted references to mbuf clusters by using the offset
of the cluster from the start of memory allocated for mbufs and
clusters as an index into an array of chars, which did the reference
counting. If the external storage was not a cluster then reference
counting had to be done by the code using that external storage.

NetBSD's system of linked lists of mbufs was cosidered, but Alfred
felt it would have locking issues when the kernel was made more
SMP friendly.

The system implimented uses a pool of unions to track external
storage. The union contains an int for counting the references and
a pointer for forming a free list. The reference counts are
incremented and decremented atomically and so should be SMP friendly.
This system can track reference counts for any sort of external
storage.

Access to the reference counting stuff is now through macros defined
in mbuf.h, so it should be easier to make changes to the system in
the future.

The possibility of storing the reference count in one of the
referencing mbufs was considered, but was rejected 'cos it would
often leave extra mbufs allocated. Storing the reference count in
the cluster was also considered, but because the external storage
may not be a cluster this isn't an option.

The size of the pool of reference counters is available in the
stats provided by "netstat -m".

PR:		19866
Submitted by:	Bosko Milekic <bmilekic@dsuper.net>
Reviewed by:	alfred (glanced at by others on -net)
2000-08-19 08:32:59 +00:00
..
bus_if.m * Factor out the object system from new-bus so that it can be used by 2000-04-08 14:17:18 +00:00
device_if.m * Factor out the object system from new-bus so that it can be used by 2000-04-08 14:17:18 +00:00
genassym.sh Use "nm | awk ..." instead of genassym(1) to generate symbol value headers. 2000-06-02 09:27:48 +00:00
imgact_aout.c Remove ~25 unneeded #include <sys/conf.h> 2000-04-19 14:58:28 +00:00
imgact_elf.c Using an atomic operation here won't help if nobody else uses them (for 2000-07-23 22:19:49 +00:00
imgact_gzip.c useracc() the prequel: 1999-10-29 18:09:36 +00:00
imgact_shell.c Fix #! script exec under linux emulation. If a script is exec'd from a 2000-04-26 20:58:40 +00:00
inflate.c Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL" 1999-12-29 05:07:58 +00:00
init_main.c Clean up some low level bootstrap code: 2000-08-11 09:05:12 +00:00
init_sysent.c Regen. (Fix SYS_exit) 2000-07-29 10:07:38 +00:00
kern_acct.c Move the truncation code out of vn_open and into the open system call 2000-07-04 03:34:11 +00:00
kern_acl.c Remove unneeded #include <vm/vm_zone.h> 2000-04-30 18:52:11 +00:00
kern_cap.c o Add missing function return types from capability syscall call stubs, 2000-07-25 03:37:36 +00:00
kern_clock.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
kern_conf.c Back out the previous change to the queue(3) interface. 2000-05-26 02:09:24 +00:00
kern_descrip.c Clean up some low level bootstrap code: 2000-08-11 09:05:12 +00:00
kern_environment.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
kern_event.c Fix bug with timeout; previously, when attempting to poll the kqueue by 2000-08-07 16:45:42 +00:00
kern_exec.c Support for unsigned integer and long sysctl variables. Update the 2000-07-05 07:46:41 +00:00
kern_exit.c Change the 'exit()' system call to 'sys_exit()'. This avoids overlapping 2000-07-29 00:16:28 +00:00
kern_fork.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
kern_intr.c Trim unused options (or #ifdef for undoc options). 1999-10-11 15:19:12 +00:00
kern_jail.c o Modify jail to limit creation of sockets to UNIX domain sockets, 2000-06-04 04:28:31 +00:00
kern_kthread.c Clean up some low level bootstrap code: 2000-08-11 09:05:12 +00:00
kern_ktrace.c Add snapshots to the fast filesystem. Most of the changes support 2000-07-11 22:07:57 +00:00
kern_linker.c Fix self referential dependencies. eg: uhub was packaged along with 2000-08-02 21:08:53 +00:00
kern_lock.c Eliminate the undocumented, experimental, non-delivering and highly 2000-03-16 08:51:55 +00:00
kern_lockf.c Commit the remaining part of PR14914: 1999-11-16 16:28:58 +00:00
kern_malloc.c Move #ifdef to the right place. 2000-06-29 09:26:26 +00:00
kern_mib.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
kern_module.c Back out the previous change to the queue(3) interface. 2000-05-26 02:09:24 +00:00
kern_ntptime.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
kern_physio.c Separate the struct bio related stuff out of <sys/buf.h> into 2000-05-05 09:59:14 +00:00
kern_proc.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
kern_prot.c fix races in the uidinfo subsystem, several problems existed: 2000-06-22 22:27:16 +00:00
kern_resource.c Fix a couple cases where p_trespass wasn't transitioned into place. 2000-08-16 23:28:54 +00:00
kern_shutdown.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
kern_sig.c Add snapshots to the fast filesystem. Most of the changes support 2000-07-11 22:07:57 +00:00
kern_subr.c Back out the previous change to the queue(3) interface. 2000-05-26 02:09:24 +00:00
kern_switch.c Commit major SMP cleanups and move the BGL (big giant lock) in the 2000-03-28 07:16:37 +00:00
kern_synch.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
kern_syscalls.c Trim unused options (or #ifdef for undoc options). 1999-10-11 15:19:12 +00:00
kern_sysctl.c Fix some style nits. 2000-07-28 22:40:04 +00:00
kern_tc.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
kern_threads.c $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
kern_time.c Remove unneeded <sys/buf.h> includes. 2000-04-18 15:15:39 +00:00
kern_timeout.c Restructure TCP timeout handling: 1999-08-30 21:17:07 +00:00
kern_xxx.c $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
ksched.c Remove unneeded #include <sys/kernel.h> 2000-04-29 15:36:14 +00:00
link_aout.c Move the truncation code out of vn_open and into the open system call 2000-07-04 03:34:11 +00:00
link_elf_obj.c Move the truncation code out of vn_open and into the open system call 2000-07-04 03:34:11 +00:00
link_elf.c Move the truncation code out of vn_open and into the open system call 2000-07-04 03:34:11 +00:00
linker_if.m First round implementation of a fine grain enhanced module to module 2000-04-29 13:19:31 +00:00
Make.tags.inc Update tags directive to reflect the new location of soft updates 2000-07-04 00:18:43 +00:00
makedevops.pl Fix some bugs in user-end output and add a reference to the original 1999-11-22 14:40:04 +00:00
Makefile ${MACHINE} -> ${MACHINE_ARCH} 1999-11-14 13:54:44 +00:00
makeobjops.pl * Factor out the object system from new-bus so that it can be used by 2000-04-08 14:17:18 +00:00
makesyscalls.sh Change the 'exit()' system call to 'sys_exit()'. This avoids overlapping 2000-07-29 00:16:28 +00:00
md5c.c Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL" 1999-12-29 05:07:58 +00:00
p1003_1b.c Add $FreeBSD$ 2000-05-01 20:32:07 +00:00
posix4_mib.c Add $FreeBSD$. 2000-04-22 15:13:06 +00:00
subr_acl_posix1e.c Remove unneeded #include <vm/vm_zone.h> 2000-04-30 18:52:11 +00:00
subr_autoconf.c Back out the previous change to the queue(3) interface. 2000-05-26 02:09:24 +00:00
subr_blist.c Eliminate the undocumented, experimental, non-delivering and highly 2000-03-16 08:51:55 +00:00
subr_bus.c Fix a const related warning. 2000-07-28 22:41:56 +00:00
subr_clist.c $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
subr_devstat.c Support for unsigned integer and long sysctl variables. Update the 2000-07-05 07:46:41 +00:00
subr_disk.c End two weeks of on and off debugging. Fix the crash on the Nth 2000-07-05 06:01:33 +00:00
subr_disklabel.c Separate the struct bio related stuff out of <sys/buf.h> into 2000-05-05 09:59:14 +00:00
subr_diskmbr.c Separate the struct bio related stuff out of <sys/buf.h> into 2000-05-05 09:59:14 +00:00
subr_diskslice.c Separate the struct bio related stuff out of <sys/buf.h> into 2000-05-05 09:59:14 +00:00
subr_eventhandler.c Back out the previous change to the queue(3) interface. 2000-05-26 02:09:24 +00:00
subr_kobj.c * Move the driver_t::refs field to kobj_t to replace kobj_t::instances. 2000-05-01 10:45:15 +00:00
subr_log.c Remove five now unused fields from struct cdevsw. They should never 1999-09-25 18:24:47 +00:00
subr_module.c Trim unused options (or #ifdef for undoc options). 1999-10-11 15:19:12 +00:00
subr_param.c Move the MSG* and SEM* options to opt_sysvipc.h 2000-05-01 13:33:56 +00:00
subr_prf.c Do not fault if curproc is null. 2000-04-29 11:32:15 +00:00
subr_prof.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
subr_rman.c Replace all the ifdef debugging spaghetti with a single ifdef and 2000-05-03 00:20:36 +00:00
subr_scanf.c Change the prototype of the strto* routines to make the second 1999-11-24 01:03:08 +00:00
subr_smp.c Clean up some low level bootstrap code: 2000-08-11 09:05:12 +00:00
subr_taskqueue.c Modify to use fixed STAILQ_LAST(). 2000-08-03 16:37:46 +00:00
subr_trap.c Change the behavior of isa_nmi to log an error message instead of 2000-08-06 14:17:21 +00:00
subr_xxx.c Remove five now unused fields from struct cdevsw. They should never 1999-09-25 18:24:47 +00:00
sys_generic.c Fix a warning that has been annoying me for some time: 2000-07-28 22:17:42 +00:00
sys_pipe.c Back out the previous change to the queue(3) interface. 2000-05-26 02:09:24 +00:00
sys_process.c Introduce the new function 1999-11-21 19:03:20 +00:00
sys_socket.c Instead of just blindly setting -rw-rw-rw-: 2000-07-02 23:56:45 +00:00
syscalls.c Regen. (Fix SYS_exit) 2000-07-29 10:07:38 +00:00
syscalls.master Sigh. Fix SYS_exit problems. I misunderstood the significance of these 2000-07-29 10:05:25 +00:00
sysv_ipc.c Remove the undocumented, flawed, broken-as-designed semconfig() syscall. 2000-05-01 11:13:41 +00:00
sysv_msg.c Move the MSG* and SEM* options to opt_sysvipc.h 2000-05-01 13:33:56 +00:00
sysv_sem.c Move the MSG* and SEM* options to opt_sysvipc.h 2000-05-01 13:33:56 +00:00
sysv_shm.c This is a cleanup patch to Peter's new OBJT_PHYS VM object type 2000-05-29 22:40:54 +00:00
tty_compat.c $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
tty_conf.c Don't refer to TABLDISC in the comments here. 2000-01-30 10:14:13 +00:00
tty_cons.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
tty_pty.c Unused include: #include "pty.h" 2000-06-10 07:12:40 +00:00
tty_snoop.c Unstaticize this driver. You can have as many snoop devices as you can 2000-04-02 00:35:37 +00:00
tty_subr.c $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
tty_tty.c Add snapshots to the fast filesystem. Most of the changes support 2000-07-11 22:07:57 +00:00
tty.c Previous commit changing SYSCTL_HANDLER_ARGS violated KNF. 2000-07-04 11:25:35 +00:00
uipc_accf.c disallow unload until we do proper refcounting 2000-07-20 12:12:41 +00:00
uipc_domain.c $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
uipc_mbuf2.c Replace the mbuf external reference counting code with something 2000-08-19 08:32:59 +00:00
uipc_mbuf.c Replace the mbuf external reference counting code with something 2000-08-19 08:32:59 +00:00
uipc_proto.c Trim unused options (or #ifdef for undoc options). 1999-10-11 15:19:12 +00:00
uipc_sockbuf.c Remove unnecessary call to splnet when setting an accept filter 2000-07-31 08:23:43 +00:00
uipc_socket2.c Remove unnecessary call to splnet when setting an accept filter 2000-07-31 08:23:43 +00:00
uipc_socket.c Make the kqueue socket read filter honor the SO_RCVLOWAT value. 2000-08-07 17:52:08 +00:00
uipc_syscalls.c Replace the mbuf external reference counting code with something 2000-08-19 08:32:59 +00:00
uipc_usrreq.c Add snapshots to the fast filesystem. Most of the changes support 2000-07-11 22:07:57 +00:00
vfs_acl.c Remove unneeded #include <vm/vm_zone.h> 2000-04-30 18:52:11 +00:00
vfs_aio.c Fix the #ifdef VFS_AIO to not compile a whole bunch of unused stuff in the 2000-07-28 23:10:10 +00:00
vfs_bio.c Now that buffer locks can be recursive, we need to delete the panics 2000-07-25 18:28:46 +00:00
vfs_cache.c Support for unsigned integer and long sysctl variables. Update the 2000-07-05 07:46:41 +00:00
vfs_cluster.c Virtualizes & untangles the bioops operations vector. 2000-06-16 08:48:51 +00:00
vfs_conf.c Make a trip to Pointy-Hats-R-Us and actually include the header that 2000-05-22 17:25:47 +00:00
vfs_default.c Introduce vop_stdinactive() and make it the default if no vop_inactive 2000-08-18 10:01:02 +00:00
vfs_export.c This patch corrects the first round of panics and hangs reported 2000-07-24 05:28:33 +00:00
vfs_extattr.c Don't set flags on the mount structure before all permission checks have 2000-08-09 01:57:11 +00:00
vfs_init.c The sysctl mod_xx hack is no longer required now that we have totally 1999-12-12 16:30:34 +00:00
vfs_lookup.c Introduce NDFREE (and remove VOP_ABORTOP) 1999-12-15 23:02:35 +00:00
vfs_mount.c Make a trip to Pointy-Hats-R-Us and actually include the header that 2000-05-22 17:25:47 +00:00
vfs_subr.c This patch corrects the first round of panics and hangs reported 2000-07-24 05:28:33 +00:00
vfs_syscalls.c Don't set flags on the mount structure before all permission checks have 2000-08-09 01:57:11 +00:00
vfs_vnops.c o Introduce vn_extattr_{get,set}, wrapper routines for VOP_GETEXTATTR 2000-08-08 17:15:32 +00:00
vnode_if.pl remove crufty exec stuff, perl is in the base system 2000-06-27 19:09:55 +00:00
vnode_if.src o Lock vnode before calling extattr_* VOP's, and modify vnode spec to 2000-07-26 20:29:20 +00:00