freebsd-skq/sys/kern
kib 031d824a49 When helping the bufdaemon from the buffer allocation context, there
is no sense to walk the whole dirty buffer queue.  We are only
interested in, and can operate on, the buffers owned by the current
vnode [1].  Instead of calling generic queue flush routine, do
VOP_FSYNC() if possible.

Holding the dirty buffer queue lock in the bufdaemon, without dropping
it, can cause starvation of buffer writes from other threads. This is
esp. easy to reproduce on the big memory machines, where large files
are written, causing almost all dirty buffers accumulating in several
big files, which vnodes are locked by writers. Bufdaemon cannot flush
any buffer, but is iterating over the whole dirty queue
continuously. Since dirty queue mutex is not dropped, bufdone() in
g_up thread is starved, usually deadlocking the machine [2]. Mitigate
this by dropping the queue lock after the vnode is locked, allowing
other queue lock contenders to make a progress.

Discussed with:	Jeff [1]
Reported by:	pho [2]
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Approved by:	re (hrs)
2013-10-02 06:00:34 +00:00
..
bus_if.m Add a BUS_CHILD_DELETED() method that a bus can hook to allow it to cleanup 2012-08-21 18:13:09 +00:00
capabilities.conf Sort properly. 2013-09-07 19:16:02 +00:00
clock_if.m
cpufreq_if.m
device_if.m Revert r239178 and implement two new functions, namely 2012-08-15 15:42:57 +00:00
dtio_kdtrace.c Change the module name for the I/O provider to "kernel" from 2012-09-25 19:16:28 +00:00
genassym.sh
imgact_aout.c Cosmetics: define FREEBSD32_MINUSER and AOUT32_MINUSER for struct 2012-07-22 13:41:45 +00:00
imgact_elf32.c
imgact_elf64.c
imgact_elf.c Add a mmap flag (MAP_32BIT) on 64-bit platforms to request that a mapping use 2013-09-09 18:11:59 +00:00
imgact_gzip.c Add a mmap flag (MAP_32BIT) on 64-bit platforms to request that a mapping use 2013-09-09 18:11:59 +00:00
imgact_shell.c The execution of the shebang script requires putting interpreter path, 2011-03-06 22:59:30 +00:00
inflate.c
init_main.c Extend the support for exempting processes from being killed when swap is 2013-09-19 18:53:42 +00:00
init_sysent.c Regen. 2013-09-19 18:56:00 +00:00
kern_acct.c acct: create a special plimit object and set it for exiting processes 2013-06-30 19:08:06 +00:00
kern_alq.c The fix committed in r250951 replaced the reported panic with a deadlock... gold 2013-06-17 09:49:07 +00:00
kern_clock.c Correct a bug that prevented deadlkres from (almost) ever firing. 2013-06-28 15:55:30 +00:00
kern_clocksource.c - Make callout(9) tickless, relying on eventtimers(4) as backend for 2013-03-04 11:09:56 +00:00
kern_condvar.c Fix lc_lock/lc_unlock() support for rmlocks held in shared mode. With 2013-09-20 23:06:21 +00:00
kern_conf.c Reject spaces and double quotation marks in device names. devctl(4) 2012-12-22 13:33:28 +00:00
kern_cons.c cngetc: use cpu_spinwait to ease the cncheckc loop a tiny bit 2012-10-06 19:50:23 +00:00
kern_context.c In order to maximize the re-usability of kernel code in user space this 2011-09-16 13:58:51 +00:00
kern_cpu.c Revert r175376 and tune cpufreq(4) frequency comparison logic instead. 2012-03-10 18:56:16 +00:00
kern_cpuset.c Several improvements to rmlock(9). Many of these are based on patches 2013-06-25 18:44:15 +00:00
kern_ctf.c Remove the support for using non-mpsafe filesystem modules. 2012-10-22 17:50:54 +00:00
kern_descrip.c it must be the last member, not might... 2013-09-26 17:55:04 +00:00
kern_dtrace.c Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs. 2011-11-07 06:44:47 +00:00
kern_environment.c r249408 and r249436 cause a NULL pointer dereference on the CUBIEBOARD 2013-04-16 22:09:08 +00:00
kern_et.c Fix incorrect assertion that caused panic when periodic-only timers used. 2013-03-13 06:42:01 +00:00
kern_event.c Do not allow negative timeouts for kqueue timers, check for the 2013-09-26 13:17:31 +00:00
kern_exec.c Change the cap_rights_t type from uint64_t to a structure that we can extend 2013-09-05 00:09:56 +00:00
kern_exit.c Specify SDT probe argument types in the probe definition itself rather than 2013-08-15 04:08:55 +00:00
kern_fail.c Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs. 2011-11-07 06:44:47 +00:00
kern_ffclock.c Revise the sysctl handling code and restructure the hierarchy of sysctls 2011-12-01 07:19:13 +00:00
kern_fork.c Extend the support for exempting processes from being killed when swap is 2013-09-19 18:53:42 +00:00
kern_gzio.c Remove the support for using non-mpsafe filesystem modules. 2012-10-22 17:50:54 +00:00
kern_hhook.c Move hhook's per-vnet initialisation to an earlier SYSINIT SI_SUB stage to 2013-06-15 10:08:34 +00:00
kern_idle.c MFC 2011-05-31 21:22:44 +00:00
kern_intr.c Snapshot; Do some running repairs on entropy harvesting. More needs to follow. 2013-08-26 18:35:21 +00:00
kern_jail.c Keep PRIV_KMEM_READ permitted inside jails as it is on the outside. 2013-09-06 17:32:29 +00:00
kern_khelp.c Cleanup and simplification in khelp_{register|deregister}_helper(). No 2013-06-15 06:45:17 +00:00
kern_kthread.c Do not use potentially stale thread in kthread_add() 2013-08-17 17:02:43 +00:00
kern_ktr.c ktr: correctly handle possible wrap-around in the boot buffer 2013-02-08 07:29:07 +00:00
kern_ktrace.c Fix panic in ktrcapfail() when no capability rights are passed. 2013-09-18 19:26:08 +00:00
kern_linker.c Rename the kld_unload event handler to kld_unload_try, and add a new 2013-08-24 21:13:38 +00:00
kern_lock.c Add LK_TRYUPGRADE operation for lockmgr(9), which attempts to 2013-09-29 18:02:23 +00:00
kern_lockf.c Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs. 2011-11-07 06:44:47 +00:00
kern_lockstat.c
kern_loginclass.c In order to maximize the re-usability of kernel code in user space this 2011-09-16 13:58:51 +00:00
kern_malloc.c - Disable quantum caches on the kmem_arena. This can make fragmentation 2013-08-13 22:41:24 +00:00
kern_mbuf.c Fixing a small typo. 2013-09-05 18:18:23 +00:00
kern_mib.c fix some fat-fingering in r246246 2013-02-02 14:19:50 +00:00
kern_module.c Fix a typo. 2012-08-22 20:01:57 +00:00
kern_mtxpool.c
kern_mutex.c Fix lc_lock/lc_unlock() support for rmlocks held in shared mode. With 2013-09-20 23:06:21 +00:00
kern_ntptime.c rename scheduler->swapper and SI_SUB_RUN_SCHEDULER->SI_SUB_LAST 2013-07-24 09:45:31 +00:00
kern_osd.c
kern_physio.c Fix some issues in change 254760 pointed out by Bruce Evans: 2013-08-29 16:41:40 +00:00
kern_pmc.c Add software PMC support. 2012-03-28 20:58:30 +00:00
kern_poll.c Remove unsigned comparison < 0 2013-08-07 07:22:56 +00:00
kern_priv.c Make the comments a little more clear about PRIV_KMEM_*, explicitly 2013-07-06 00:10:52 +00:00
kern_proc.c Extend the support for exempting processes from being killed when swap is 2013-09-19 18:53:42 +00:00
kern_prot.c Style fix 2012-11-14 10:33:12 +00:00
kern_racct.c Accessing td_state requires thread lock to be held. 2013-03-14 23:20:18 +00:00
kern_rangelock.c Change the queue of locks in kern_rangelock.c from holding lock requests in 2013-08-15 20:19:17 +00:00
kern_rctl.c Add CPU percentage limit enforcement to RCTL. The resouce name is "pcpu". 2012-10-26 16:01:08 +00:00
kern_resource.c Call sched_prio() to immediately change the priority of the thread in 2013-03-07 02:53:29 +00:00
kern_rmlock.c Fix lc_lock/lc_unlock() support for rmlocks held in shared mode. With 2013-09-20 23:06:21 +00:00
kern_rwlock.c Consistently use the same value to indicate exclusively-held and 2013-09-22 14:09:07 +00:00
kern_sdt.c FreeBSD's DTrace implementation has a few problems with respect to handling 2013-08-13 03:10:39 +00:00
kern_sema.c
kern_sharedpage.c Remove the deprecated VM_ALLOC_RETRY flag for the vm_page_grab(9). 2013-08-22 07:39:53 +00:00
kern_shutdown.c Switch vm_object lock to be a rwlock. 2013-02-20 10:38:34 +00:00
kern_sig.c Change the cap_rights_t type from uint64_t to a structure that we can extend 2013-09-05 00:09:56 +00:00
kern_switch.c Add a comment on why inlining critical_enter() may not be a good idea 2012-12-09 04:54:22 +00:00
kern_sx.c Consistently use the same value to indicate exclusively-held and 2013-09-22 14:09:07 +00:00
kern_synch.c Make load average sampling asynchronous to hardclock ticks. This improves 2013-09-24 07:03:16 +00:00
kern_syscalls.c
kern_sysctl.c Add a helpful message that can help point to why a sysctl tree removal failed 2013-08-09 01:04:44 +00:00
kern_tc.c - Make callout(9) tickless, relying on eventtimers(4) as backend for 2013-03-04 11:09:56 +00:00
kern_thr.c Stop treating td_sigmask specially for the purposes of new thread 2012-05-26 20:03:47 +00:00
kern_thread.c Another NFS SIGSTOP related fix: Ignore thread suspend requests due to 2013-03-21 14:06:27 +00:00
kern_time.c Implement compat32 wrappers for the ktimer_* syscalls. 2013-07-21 19:43:52 +00:00
kern_timeout.c Make the callout arithmetic more robust adding checks for overflow. 2013-09-26 10:06:50 +00:00
kern_umtx.c Fix two issues with the spin loops in the umtx(2) implementation. 2013-06-13 09:33:22 +00:00
kern_uuid.c Further restrict the MAC addresses that we use for UUID generation 2013-07-24 18:13:43 +00:00
kern_xxx.c
ksched.c sched_rr_interval() seems always returned period in hz ticks, but same 2012-08-10 18:19:57 +00:00
link_elf_obj.c Add a mmap flag (MAP_32BIT) on 64-bit platforms to request that a mapping use 2013-09-09 18:11:59 +00:00
link_elf.c Add a mmap flag (MAP_32BIT) on 64-bit platforms to request that a mapping use 2013-09-09 18:11:59 +00:00
linker_if.m
Make.tags.inc - Trim an unused and bogus Makefile for mount_smbfs. 2013-06-28 21:00:08 +00:00
Makefile Continue to introduce Capsicum Capability Mode support: 2011-03-01 13:28:27 +00:00
makesyscalls.sh Omit "__restrict" when generating syscall argument strings. DTrace doesn't 2013-09-21 23:05:44 +00:00
md4c.c
md5c.c
p1003_1b.c In order to maximize the re-usability of kernel code in user space this 2011-09-16 13:58:51 +00:00
posix4_mib.c Define two new sysctl node flags: CTLFLAG_CAPRD and CTLFLAG_CAPRW, which 2011-07-17 23:05:24 +00:00
sched_4bsd.c rename scheduler->swapper and SI_SUB_RUN_SCHEDULER->SI_SUB_LAST 2013-07-24 09:45:31 +00:00
sched_ule.c Micro-optimize cpu_search(), allowing compiler to use more efficient inline 2013-09-07 15:16:30 +00:00
serdev_if.m
stack_protector.c
subr_acl_nfs4.c Fix bug where NFSv4 ACL enforcement code wouldn't unconditionally 2012-04-17 14:54:00 +00:00
subr_acl_posix1e.c Add module load/unload stubs. 2012-03-13 20:27:48 +00:00
subr_autoconf.c
subr_blist.c Remove reference to the rlist code from comments, and fix a typo visible 2013-02-05 20:08:33 +00:00
subr_bufring.c
subr_bus_dma.c Move an assertion to the right spot; only bus_dmamap_load_mbuf(9) 2013-06-01 11:42:47 +00:00
subr_bus.c Allow drivers to return BUS_PROBE_NOWILDCARD from their attach routine to 2013-08-08 19:30:49 +00:00
subr_busdma_bufalloc.c Replace kernel virtual address space allocation with vmem. This provides 2013-08-07 06:21:20 +00:00
subr_capability.c Fix panic in cap_rights_is_valid() when invalid rights are provided - 2013-09-07 19:03:16 +00:00
subr_clock.c
subr_counter.c Revert r249590 and in case if mp_ncpus isn't initialized use MAXCPU. This 2013-07-23 11:16:40 +00:00
subr_devstat.c Fix build for kernels with dtrace hooks. 2012-07-11 18:50:50 +00:00
subr_disk.c
subr_dummy_vdso_tc.c Implement mechanism to export some kernel timekeeping data to 2012-06-22 07:06:40 +00:00
subr_eventhandler.c
subr_fattime.c
subr_firmware.c Correct sizeof usage 2012-06-25 05:41:16 +00:00
subr_hash.c Convert panic()s to KASSERT()s. This is an optimisation for 2012-01-23 16:31:46 +00:00
subr_hints.c Style fixes. 2012-09-04 23:16:55 +00:00
subr_kdb.c - Extend the KDB interface to add a per-debugger callback to print a 2012-04-12 17:43:59 +00:00
subr_kobj.c As it turns out, r186347 actually is insufficient to avoid the use of the 2011-11-15 20:11:03 +00:00
subr_lock.c Several improvements to rmlock(9). Many of these are based on patches 2013-06-25 18:44:15 +00:00
subr_log.c MFcalloutng (r244255 by mav, with minor changes): 2013-03-04 16:07:55 +00:00
subr_mbpool.c Give (*ext_free) an int return value allowing for very sophisticated 2013-08-25 10:57:09 +00:00
subr_mchain.c Mechanically substitute flags from historic mbuf allocator with 2012-12-05 08:04:20 +00:00
subr_module.c Provide convenience function for obtaining MODINFO_ADDR and MODINFO_SIZE 2011-02-09 19:08:21 +00:00
subr_msgbuf.c - Clean up timestamps in msgbuf code. The timestamps should now be 2012-03-19 00:36:32 +00:00
subr_param.c Implement the concept of the unmapped VMIO buffers, i.e. buffers which 2013-03-19 14:13:12 +00:00
subr_pcpu.c Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs. 2011-11-07 06:44:47 +00:00
subr_pctrie.c - Add a new general purpose path-compressed radix trie which can be used 2013-05-12 04:05:01 +00:00
subr_power.c
subr_prf.c Reduce the scope of the proctree_lock. If several processes cause 2013-09-13 06:39:10 +00:00
subr_prof.c Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs. 2011-11-07 15:43:11 +00:00
subr_rman.c Unlock in the error path to prevent a lock leak. 2012-05-31 17:27:05 +00:00
subr_rtc.c Core structure and functions to support a feed-forward clock within the kernel. 2011-11-19 14:10:16 +00:00
subr_sbuf.c Always request zeroed memory, in case we're dumb enough to leak it later. 2013-09-22 23:47:56 +00:00
subr_scanf.c Xen netback driver rewrite. 2012-01-26 16:35:09 +00:00
subr_sglist.c
subr_sleepqueue.c Partially revert r195702. Deferring stops is now implemented via a set of 2013-03-18 17:23:58 +00:00
subr_smp.c Fix ia64 and mips kernel builds due to XENHVM=>GENERIC integration in 2013-09-22 02:46:13 +00:00
subr_stack.c Constify stack argument for functions that don't modify it. 2011-11-16 19:06:55 +00:00
subr_syscall.c Fix build on ARM (and probably other platforms) 2012-12-28 06:52:53 +00:00
subr_taskqueue.c MFprojects/camlock r254460: 2013-08-24 14:41:49 +00:00
subr_trap.c Partially revert r195702. Deferring stops is now implemented via a set of 2013-03-18 17:23:58 +00:00
subr_turnstile.c Update the comment: we do show the backtrace of misbehaving thread. 2013-02-17 21:37:32 +00:00
subr_uio.c Remove zero-copy sockets code. It only worked for anonymous memory, 2013-09-16 06:25:54 +00:00
subr_unit.c Move the definition of the struct unrhdr into a separate header file, 2013-08-30 07:37:45 +00:00
subr_vmem.c Added sysctl to turn off calls to vmem_check(). 2013-08-20 11:06:56 +00:00
subr_witness.c Trim a couple of panic messages. 2013-09-04 11:52:28 +00:00
sys_capability.c This looks like a typo that breaks the build. Yell at me if this isn't the 2013-09-05 03:36:57 +00:00
sys_generic.c Restore builds on architectures that don't support CAPABILITIES (mips). 2013-09-05 03:46:44 +00:00
sys_pipe.c Add a mmap flag (MAP_32BIT) on 64-bit platforms to request that a mapping use 2013-09-09 18:11:59 +00:00
sys_procdesc.c Change the cap_rights_t type from uint64_t to a structure that we can extend 2013-09-05 00:09:56 +00:00
sys_process.c Extend the support for exempting processes from being killed when swap is 2013-09-19 18:53:42 +00:00
sys_socket.c Make sendfile() a method in the struct fileops. Currently only 2013-08-15 07:54:31 +00:00
syscalls.c Regen. 2013-09-19 18:56:00 +00:00
syscalls.master Extend the support for exempting processes from being killed when swap is 2013-09-19 18:53:42 +00:00
systrace_args.c Regenerate syscall argument strings after r255777. 2013-09-21 23:06:36 +00:00
sysv_ipc.c
sysv_msg.c In order to maximize the re-usability of kernel code in user space this 2011-09-16 13:58:51 +00:00
sysv_sem.c In order to maximize the re-usability of kernel code in user space this 2011-09-16 13:58:51 +00:00
sysv_shm.c Add a mmap flag (MAP_32BIT) on 64-bit platforms to request that a mapping use 2013-09-09 18:11:59 +00:00
tty_compat.c
tty_info.c Fix whitespace inconsistencies in TTY code. 2012-02-06 18:15:46 +00:00
tty_inq.c Use strchr() and strrchr(). 2012-01-02 12:12:10 +00:00
tty_outq.c Fix whitespace inconsistencies in the TTY layer and its drivers owned by me. 2011-06-26 18:26:20 +00:00
tty_pts.c Make sendfile() a method in the struct fileops. Currently only 2013-08-15 07:54:31 +00:00
tty_tty.c
tty_ttydisc.c Correct SIGTTIN handling. 2012-10-25 09:05:21 +00:00
tty.c Change the cap_rights_t type from uint64_t to a structure that we can extend 2013-09-05 00:09:56 +00:00
uipc_accf.c
uipc_cow.c Give (*ext_free) an int return value allowing for very sophisticated 2013-08-25 10:57:09 +00:00
uipc_debug.c Fix socket buffer timeouts precision using the new sbintime_t KPI instead 2013-09-01 23:34:53 +00:00
uipc_domain.c - Implement two new system calls: 2013-03-02 21:11:30 +00:00
uipc_mbuf2.c Mechanically substitute flags from historic mbuf allocator with 2012-12-05 08:04:20 +00:00
uipc_mbuf.c Pad m_hdr on 32bit architectures to to prevent alignment and padding 2013-08-27 20:52:02 +00:00
uipc_mqueue.c Fix !CAPABILITIES build. 2013-09-05 10:24:09 +00:00
uipc_sem.c Change the cap_rights_t type from uint64_t to a structure that we can extend 2013-09-05 00:09:56 +00:00
uipc_shm.c Implement sendfile(2) for the posix shared memory segment file descriptor, 2013-09-11 06:41:15 +00:00
uipc_sockbuf.c Fix socket buffer timeouts precision using the new sbintime_t KPI instead 2013-09-01 23:34:53 +00:00
uipc_socket.c Remove zero-copy sockets code. It only worked for anonymous memory, 2013-09-16 06:25:54 +00:00
uipc_syscalls.c - Create kern.ipc.sendfile namespace, and put the new "readhead" OID 2013-09-22 13:36:52 +00:00
uipc_usrreq.c Provide pr_ctloutput method for AF_LOCAL/SOCK_SEQPACKET sockets. 2013-09-11 18:22:30 +00:00
vfs_acl.c Change the cap_rights_t type from uint64_t to a structure that we can extend 2013-09-05 00:09:56 +00:00
vfs_aio.c The fget() function now takes pointer to cap_rights_t, so change 0 to NULL. 2013-09-05 11:59:23 +00:00
vfs_bio.c When helping the bufdaemon from the buffer allocation context, there 2013-10-02 06:00:34 +00:00
vfs_cache.c namecache sdt: freebsd doesn't support structured characters yet 2013-07-09 08:58:34 +00:00
vfs_cluster.c When allocating a pbuf for the cluster write, do not sleep waiting 2013-08-27 01:31:12 +00:00
vfs_default.c - Convert the bufobj lock to rwlock. 2013-05-31 00:43:41 +00:00
vfs_export.c MFC 2013-02-21 21:59:35 +00:00
vfs_extattr.c Change the cap_rights_t type from uint64_t to a structure that we can extend 2013-09-05 00:09:56 +00:00
vfs_hash.c Add exported vfs_hash_index() function, which calculates the canonical 2013-01-14 05:41:40 +00:00
vfs_init.c Revert accidental commit. 2013-06-29 05:05:57 +00:00
vfs_lookup.c Fix panic in ktrcapfail() when no capability rights are passed. 2013-09-18 19:26:08 +00:00
vfs_mount.c Forced dismounts of NFS mounts can fail when thread(s) are stuck 2013-09-01 23:02:59 +00:00
vfs_mountroot.c In r243868, the error message buffer errmsg have been changed from 2013-09-09 05:01:18 +00:00
vfs_subr.c When printing the vnode information from ddb, print the lengths of the 2013-10-01 20:18:33 +00:00
vfs_syscalls.c Correct the logic broken in my last commit. 2013-09-05 09:36:19 +00:00
vfs_vnops.c When opening or closing fifo, ensure that the vnode is locked 2013-09-13 06:52:23 +00:00
vnode_if.src remove vop_lookup_pre and vop_lookup_post 2012-11-22 10:36:10 +00:00