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Make.tags.inc
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Makefile
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bus_if.m
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capabilities.conf
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clock_if.m
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cpufreq_if.m
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device_if.m
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firmw.S
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genassym.sh
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genoffset.c
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genoffset.sh
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imgact_aout.c
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imgact_binmisc.c
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imgact_elf.c
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imgact_elf32.c
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imgact_elf64.c
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imgact_shell.c
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init_main.c
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init_sysent.c
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kern_acct.c
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kern_alq.c
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kern_clock.c
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kern_clocksource.c
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kern_condvar.c
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kern_conf.c
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kern_cons.c
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kern_context.c
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kern_cpu.c
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kern_cpuset.c
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kern_ctf.c
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kern_descrip.c
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kern_dtrace.c
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kern_dump.c
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kern_environment.c
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kern_et.c
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kern_event.c
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kern_exec.c
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kern_exit.c
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kern_fail.c
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kern_ffclock.c
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kern_fork.c
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kern_hhook.c
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kern_idle.c
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kern_intr.c
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kern_jail.c
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kern_kcov.c
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kern_khelp.c
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kern_kthread.c
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kern_ktr.c
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kern_ktrace.c
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kern_linker.c
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kern_lock.c
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kern_lockf.c
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kern_lockstat.c
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kern_loginclass.c
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kern_malloc.c
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kern_mbuf.c
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kern_mib.c
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kern_module.c
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kern_mtxpool.c
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kern_mutex.c
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kern_ntptime.c
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kern_osd.c
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kern_physio.c
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kern_pmc.c
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kern_poll.c
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kern_priv.c
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kern_proc.c
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kern_procctl.c
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kern_prot.c
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kern_racct.c
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kern_rangelock.c
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kern_rctl.c
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kern_resource.c
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kern_rmlock.c
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kern_rwlock.c
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kern_sdt.c
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kern_sema.c
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kern_sendfile.c
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kern_sharedpage.c
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kern_shutdown.c
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kern_sig.c
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kern_switch.c
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kern_sx.c
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kern_synch.c
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kern_syscalls.c
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kern_sysctl.c
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kern_tc.c
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kern_thr.c
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kern_thread.c
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kern_time.c
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kern_timeout.c
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kern_tslog.c
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kern_ubsan.c
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kern_umtx.c
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kern_uuid.c
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kern_xxx.c
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ksched.c
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link_elf.c
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link_elf_obj.c
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linker_if.m
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makesyscalls.sh
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md4c.c
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md5c.c
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msi_if.m
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p1003_1b.c
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pic_if.m
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posix4_mib.c
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sched_4bsd.c
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sched_ule.c
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serdev_if.m
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stack_protector.c
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subr_acl_nfs4.c
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subr_acl_posix1e.c
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subr_atomic64.c
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subr_autoconf.c
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subr_blist.c
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subr_boot.c
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subr_bufring.c
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subr_bus.c
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subr_bus_dma.c
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subr_busdma_bufalloc.c
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subr_capability.c
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subr_clock.c
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subr_compressor.c
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subr_counter.c
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subr_coverage.c
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subr_csan.c
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subr_devmap.c
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subr_devstat.c
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subr_disk.c
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subr_dummy_vdso_tc.c
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subr_early.c
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subr_epoch.c
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subr_eventhandler.c
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subr_fattime.c
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subr_filter.c
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subr_firmware.c
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subr_gtaskqueue.c
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subr_hash.c
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subr_hints.c
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subr_intr.c
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subr_kdb.c
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subr_kobj.c
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subr_lock.c
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subr_log.c
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subr_mchain.c
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subr_module.c
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subr_msgbuf.c
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subr_param.c
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subr_pcpu.c
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subr_pctrie.c
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subr_physmem.c
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subr_pidctrl.c
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subr_power.c
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subr_prf.c
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subr_prng.c
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subr_prof.c
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subr_rangeset.c
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subr_rman.c
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subr_rtc.c
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subr_sbuf.c
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subr_scanf.c
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subr_sfbuf.c
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subr_sglist.c
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subr_sleepqueue.c
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subr_smp.c
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subr_smr.c
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subr_stack.c
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subr_stats.c
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subr_syscall.c
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subr_taskqueue.c
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subr_terminal.c
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subr_trap.c
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subr_turnstile.c
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subr_uio.c
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subr_unit.c
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subr_vmem.c
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subr_witness.c
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sys_capability.c
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sys_eventfd.c
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sys_generic.c
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sys_getrandom.c
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sys_pipe.c
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sys_procdesc.c
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sys_process.c
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sys_socket.c
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syscalls.c
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syscalls.master
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systrace_args.c
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sysv_ipc.c
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sysv_msg.c
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sysv_sem.c
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sysv_shm.c
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tty.c
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tty_compat.c
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tty_info.c
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tty_inq.c
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tty_outq.c
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tty_pts.c
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tty_tty.c
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tty_ttydisc.c
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uipc_accf.c
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uipc_debug.c
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uipc_domain.c
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uipc_ktls.c
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uipc_mbuf.c
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uipc_mbuf2.c
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uipc_mbufhash.c
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uipc_mqueue.c
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uipc_sem.c
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uipc_shm.c
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uipc_sockbuf.c
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uipc_socket.c
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uipc_syscalls.c
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uipc_usrreq.c
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vfs_acl.c
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vfs_aio.c
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vfs_bio.c
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vfs_cache.c
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vfs_cluster.c
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vfs_default.c
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vfs_export.c
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vfs_extattr.c
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vfs_hash.c
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vfs_init.c
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vfs_lookup.c
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vfs_mount.c
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vfs_mountroot.c
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vfs_subr.c
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vfs_syscalls.c
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vfs_vnops.c
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vnode_if.src
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Editing: subr_devstat.c
/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1997, 1998, 1999 Kenneth D. Merry. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <sys/cdefs.h> __FBSDID("$FreeBSD$"); #include <sys/param.h> #include <sys/kernel.h> #include <sys/systm.h> #include <sys/bio.h> #include <sys/devicestat.h> #include <sys/sdt.h> #include <sys/sysctl.h> #include <sys/malloc.h> #include <sys/lock.h> #include <sys/mutex.h> #include <sys/conf.h> #include <vm/vm.h> #include <vm/pmap.h> #include <machine/atomic.h> SDT_PROVIDER_DEFINE(io); SDT_PROBE_DEFINE2(io, , , start, "struct bio *", "struct devstat *"); SDT_PROBE_DEFINE2(io, , , done, "struct bio *", "struct devstat *"); SDT_PROBE_DEFINE2(io, , , wait__start, "struct bio *", "struct devstat *"); SDT_PROBE_DEFINE2(io, , , wait__done, "struct bio *", "struct devstat *"); #define DTRACE_DEVSTAT_START() SDT_PROBE2(io, , , start, NULL, ds) #define DTRACE_DEVSTAT_BIO_START() SDT_PROBE2(io, , , start, bp, ds) #define DTRACE_DEVSTAT_DONE() SDT_PROBE2(io, , , done, NULL, ds) #define DTRACE_DEVSTAT_BIO_DONE() SDT_PROBE2(io, , , done, bp, ds) #define DTRACE_DEVSTAT_WAIT_START() SDT_PROBE2(io, , , wait__start, NULL, ds) #define DTRACE_DEVSTAT_WAIT_DONE() SDT_PROBE2(io, , , wait__done, NULL, ds) static int devstat_num_devs; static long devstat_generation = 1; static int devstat_version = DEVSTAT_VERSION; static int devstat_current_devnumber; static struct mtx devstat_mutex; MTX_SYSINIT(devstat_mutex, &devstat_mutex, "devstat", MTX_DEF); static struct devstatlist device_statq = STAILQ_HEAD_INITIALIZER(device_statq); static struct devstat *devstat_alloc(void); static void devstat_free(struct devstat *); static void devstat_add_entry(struct devstat *ds, const void *dev_name, int unit_number, uint32_t block_size, devstat_support_flags flags, devstat_type_flags device_type, devstat_priority priority); /* * Allocate a devstat and initialize it */ struct devstat * devstat_new_entry(const void *dev_name, int unit_number, uint32_t block_size, devstat_support_flags flags, devstat_type_flags device_type, devstat_priority priority) { struct devstat *ds; mtx_assert(&devstat_mutex, MA_NOTOWNED); ds = devstat_alloc(); mtx_lock(&devstat_mutex); if (unit_number == -1) { ds->unit_number = unit_number; ds->id = dev_name; binuptime(&ds->creation_time); devstat_generation++; } else { devstat_add_entry(ds, dev_name, unit_number, block_size, flags, device_type, priority); } mtx_unlock(&devstat_mutex); return (ds); } /* * Take a malloced and zeroed devstat structure given to us, fill it in * and add it to the queue of devices. */ static void devstat_add_entry(struct devstat *ds, const void *dev_name, int unit_number, uint32_t block_size, devstat_support_flags flags, devstat_type_flags device_type, devstat_priority priority) { struct devstatlist *devstat_head; struct devstat *ds_tmp; mtx_assert(&devstat_mutex, MA_OWNED); devstat_num_devs++; devstat_head = &device_statq; /* * Priority sort. Each driver passes in its priority when it adds * its devstat entry. Drivers are sorted first by priority, and * then by probe order. * * For the first device, we just insert it, since the priority * doesn't really matter yet. Subsequent devices are inserted into * the list using the order outlined above. */ if (devstat_num_devs == 1) STAILQ_INSERT_TAIL(devstat_head, ds, dev_links); else { STAILQ_FOREACH(ds_tmp, devstat_head, dev_links) { struct devstat *ds_next; ds_next = STAILQ_NEXT(ds_tmp, dev_links); /* * If we find a break between higher and lower * priority items, and if this item fits in the * break, insert it. This also applies if the * "lower priority item" is the end of the list. */ if ((priority <= ds_tmp->priority) && ((ds_next == NULL) || (priority > ds_next->priority))) { STAILQ_INSERT_AFTER(devstat_head, ds_tmp, ds, dev_links); break; } else if (priority > ds_tmp->priority) { /* * If this is the case, we should be able * to insert ourselves at the head of the * list. If we can't, something is wrong. */ if (ds_tmp == STAILQ_FIRST(devstat_head)) { STAILQ_INSERT_HEAD(devstat_head, ds, dev_links); break; } else { STAILQ_INSERT_TAIL(devstat_head, ds, dev_links); printf("devstat_add_entry: HELP! " "sorting problem detected " "for name %p unit %d\n", dev_name, unit_number); break; } } } } ds->device_number = devstat_current_devnumber++; ds->unit_number = unit_number; strlcpy(ds->device_name, dev_name, DEVSTAT_NAME_LEN); ds->block_size = block_size; ds->flags = flags; ds->device_type = device_type; ds->priority = priority; binuptime(&ds->creation_time); devstat_generation++; } /* * Remove a devstat structure from the list of devices. */ void devstat_remove_entry(struct devstat *ds) { struct devstatlist *devstat_head; mtx_assert(&devstat_mutex, MA_NOTOWNED); if (ds == NULL) return; mtx_lock(&devstat_mutex); devstat_head = &device_statq; /* Remove this entry from the devstat queue */ atomic_add_acq_int(&ds->sequence1, 1); if (ds->unit_number != -1) { devstat_num_devs--; STAILQ_REMOVE(devstat_head, ds, devstat, dev_links); } devstat_free(ds); devstat_generation++; mtx_unlock(&devstat_mutex); } /* * Record a transaction start. * * See comments for devstat_end_transaction(). Ordering is very important * here. */ void devstat_start_transaction(struct devstat *ds, const struct bintime *now) { /* sanity check */ if (ds == NULL) return; atomic_add_acq_int(&ds->sequence1, 1); /* * We only want to set the start time when we are going from idle * to busy. The start time is really the start of the latest busy * period. */ if (atomic_fetchadd_int(&ds->start_count, 1) == ds->end_count) { if (now != NULL) ds->busy_from = *now; else binuptime(&ds->busy_from); } atomic_add_rel_int(&ds->sequence0, 1); DTRACE_DEVSTAT_START(); } void devstat_start_transaction_bio(struct devstat *ds, struct bio *bp) { /* sanity check */ if (ds == NULL) return; binuptime(&bp->bio_t0); devstat_start_transaction_bio_t0(ds, bp); } void devstat_start_transaction_bio_t0(struct devstat *ds, struct bio *bp) { /* sanity check */ if (ds == NULL) return; devstat_start_transaction(ds, &bp->bio_t0); DTRACE_DEVSTAT_BIO_START(); } /* * Record the ending of a transaction, and incrment the various counters. * * Ordering in this function, and in devstat_start_transaction() is VERY * important. The idea here is to run without locks, so we are very * careful to only modify some fields on the way "down" (i.e. at * transaction start) and some fields on the way "up" (i.e. at transaction * completion). One exception is busy_from, which we only modify in * devstat_start_transaction() when there are no outstanding transactions, * and thus it can't be modified in devstat_end_transaction() * simultaneously. * * The sequence0 and sequence1 fields are provided to enable an application * spying on the structures with mmap(2) to tell when a structure is in a * consistent state or not. * * For this to work 100% reliably, it is important that the two fields * are at opposite ends of the structure and that they are incremented * in the opposite order of how a memcpy(3) in userland would copy them. * We assume that the copying happens front to back, but there is actually * no way short of writing your own memcpy(3) replacement to guarantee * this will be the case. * * In addition to this, being a kind of locks, they must be updated with * atomic instructions using appropriate memory barriers. */ void devstat_end_transaction(struct devstat *ds, uint32_t bytes, devstat_tag_type tag_type, devstat_trans_flags flags, const struct bintime *now, const struct bintime *then) { struct bintime dt, lnow; /* sanity check */ if (ds == NULL) return; if (now == NULL) { binuptime(&lnow); now = &lnow; } atomic_add_acq_int(&ds->sequence1, 1); /* Update byte and operations counts */ ds->bytes[flags] += bytes; ds->operations[flags]++; /* * Keep a count of the various tag types sent. */ if ((ds->flags & DEVSTAT_NO_ORDERED_TAGS) == 0 && tag_type != DEVSTAT_TAG_NONE) ds->tag_types[tag_type]++; if (then != NULL) { /* Update duration of operations */ dt = *now; bintime_sub(&dt, then); bintime_add(&ds->duration[flags], &dt); } /* Accumulate busy time */ dt = *now; bintime_sub(&dt, &ds->busy_from); bintime_add(&ds->busy_time, &dt); ds->busy_from = *now; ds->end_count++; atomic_add_rel_int(&ds->sequence0, 1); DTRACE_DEVSTAT_DONE(); } void devstat_end_transaction_bio(struct devstat *ds, const struct bio *bp) { devstat_end_transaction_bio_bt(ds, bp, NULL); } void devstat_end_transaction_bio_bt(struct devstat *ds, const struct bio *bp, const struct bintime *now) { devstat_trans_flags flg; devstat_tag_type tag; /* sanity check */ if (ds == NULL) return; if (bp->bio_flags & BIO_ORDERED) tag = DEVSTAT_TAG_ORDERED; else tag = DEVSTAT_TAG_SIMPLE; if (bp->bio_cmd == BIO_DELETE) flg = DEVSTAT_FREE; else if ((bp->bio_cmd == BIO_READ) || ((bp->bio_cmd == BIO_ZONE) && (bp->bio_zone.zone_cmd == DISK_ZONE_REPORT_ZONES))) flg = DEVSTAT_READ; else if (bp->bio_cmd == BIO_WRITE) flg = DEVSTAT_WRITE; else flg = DEVSTAT_NO_DATA; devstat_end_transaction(ds, bp->bio_bcount - bp->bio_resid, tag, flg, now, &bp->bio_t0); DTRACE_DEVSTAT_BIO_DONE(); } /* * This is the sysctl handler for the devstat package. The data pushed out * on the kern.devstat.all sysctl variable consists of the current devstat * generation number, and then an array of devstat structures, one for each * device in the system. * * This is more cryptic that obvious, but basically we neither can nor * want to hold the devstat_mutex for any amount of time, so we grab it * only when we need to and keep an eye on devstat_generation all the time. */ static int sysctl_devstat(SYSCTL_HANDLER_ARGS) { int error; long mygen; struct devstat *nds; mtx_assert(&devstat_mutex, MA_NOTOWNED); /* * XXX devstat_generation should really be "volatile" but that * XXX freaks out the sysctl macro below. The places where we * XXX change it and inspect it are bracketed in the mutex which * XXX guarantees us proper write barriers. I don't believe the * XXX compiler is allowed to optimize mygen away across calls * XXX to other functions, so the following is belived to be safe. */ mygen = devstat_generation; error = SYSCTL_OUT(req, &mygen, sizeof(mygen)); if (devstat_num_devs == 0) return(0); if (error != 0) return (error); mtx_lock(&devstat_mutex); nds = STAILQ_FIRST(&device_statq); if (mygen != devstat_generation) error = EBUSY; mtx_unlock(&devstat_mutex); if (error != 0) return (error); for (;nds != NULL;) { error = SYSCTL_OUT(req, nds, sizeof(struct devstat)); if (error != 0) return (error); mtx_lock(&devstat_mutex); if (mygen != devstat_generation) error = EBUSY; else nds = STAILQ_NEXT(nds, dev_links); mtx_unlock(&devstat_mutex); if (error != 0) return (error); } return(error); } /* * Sysctl entries for devstat. The first one is a node that all the rest * hang off of. */ static SYSCTL_NODE(_kern, OID_AUTO, devstat, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "Device Statistics"); SYSCTL_PROC(_kern_devstat, OID_AUTO, all, CTLFLAG_RD | CTLTYPE_OPAQUE | CTLFLAG_MPSAFE, NULL, 0, sysctl_devstat, "S,devstat", "All devices in the devstat list"); /* * Export the number of devices in the system so that userland utilities * can determine how much memory to allocate to hold all the devices. */ SYSCTL_INT(_kern_devstat, OID_AUTO, numdevs, CTLFLAG_RD, &devstat_num_devs, 0, "Number of devices in the devstat list"); SYSCTL_LONG(_kern_devstat, OID_AUTO, generation, CTLFLAG_RD, &devstat_generation, 0, "Devstat list generation"); SYSCTL_INT(_kern_devstat, OID_AUTO, version, CTLFLAG_RD, &devstat_version, 0, "Devstat list version number"); /* * Allocator for struct devstat structures. We sub-allocate these from pages * which we get from malloc. These pages are exported for mmap(2)'ing through * a miniature device driver */ #define statsperpage (PAGE_SIZE / sizeof(struct devstat)) static d_mmap_t devstat_mmap; static struct cdevsw devstat_cdevsw = { .d_version = D_VERSION, .d_mmap = devstat_mmap, .d_name = "devstat", }; struct statspage { TAILQ_ENTRY(statspage) list; struct devstat *stat; u_int nfree; }; static TAILQ_HEAD(, statspage) pagelist = TAILQ_HEAD_INITIALIZER(pagelist); static MALLOC_DEFINE(M_DEVSTAT, "devstat", "Device statistics"); static int devstat_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, int nprot, vm_memattr_t *memattr) { struct statspage *spp; if (nprot != VM_PROT_READ) return (-1); mtx_lock(&devstat_mutex); TAILQ_FOREACH(spp, &pagelist, list) { if (offset == 0) { *paddr = vtophys(spp->stat); mtx_unlock(&devstat_mutex); return (0); } offset -= PAGE_SIZE; } mtx_unlock(&devstat_mutex); return (-1); } static struct devstat * devstat_alloc(void) { struct devstat *dsp; struct statspage *spp, *spp2; u_int u; static int once; mtx_assert(&devstat_mutex, MA_NOTOWNED); if (!once) { make_dev_credf(MAKEDEV_ETERNAL | MAKEDEV_CHECKNAME, &devstat_cdevsw, 0, NULL, UID_ROOT, GID_WHEEL, 0444, DEVSTAT_DEVICE_NAME); once = 1; } spp2 = NULL; mtx_lock(&devstat_mutex); for (;;) { TAILQ_FOREACH(spp, &pagelist, list) { if (spp->nfree > 0) break; } if (spp != NULL) break; mtx_unlock(&devstat_mutex); spp2 = malloc(sizeof *spp, M_DEVSTAT, M_ZERO | M_WAITOK); spp2->stat = malloc(PAGE_SIZE, M_DEVSTAT, M_ZERO | M_WAITOK); spp2->nfree = statsperpage; /* * If free statspages were added while the lock was released * just reuse them. */ mtx_lock(&devstat_mutex); TAILQ_FOREACH(spp, &pagelist, list) if (spp->nfree > 0) break; if (spp == NULL) { spp = spp2; /* * It would make more sense to add the new page at the * head but the order on the list determine the * sequence of the mapping so we can't do that. */ TAILQ_INSERT_TAIL(&pagelist, spp, list); } else break; } dsp = spp->stat; for (u = 0; u < statsperpage; u++) { if (dsp->allocated == 0) break; dsp++; } spp->nfree--; dsp->allocated = 1; mtx_unlock(&devstat_mutex); if (spp2 != NULL && spp2 != spp) { free(spp2->stat, M_DEVSTAT); free(spp2, M_DEVSTAT); } return (dsp); } static void devstat_free(struct devstat *dsp) { struct statspage *spp; mtx_assert(&devstat_mutex, MA_OWNED); bzero(dsp, sizeof *dsp); TAILQ_FOREACH(spp, &pagelist, list) { if (dsp >= spp->stat && dsp < (spp->stat + statsperpage)) { spp->nfree++; return; } } } SYSCTL_INT(_debug_sizeof, OID_AUTO, devstat, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, sizeof(struct devstat), "sizeof(struct devstat)");
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