$NetBSD: README,v 1.3 2008/01/02 01:17:41 yamt Exp $
NOTE:
- tprof driver currently only supports pentium4 (netburst) processors.
- it samples program counters on every PMIs.
- it's currently hardcoded to use global_power_events events.
for details, see x86/x86/tprof_pmi.c and intel's processor manuals.
- it doesn't work for amd64 due to a bug. see PR/37662.
usage:
1. add a line to your kernel config.
pseudo-device tprof
2. create a device special file.
# mknod /dev/tprof c 191 0
3. run the tprof command.
# tprof -o /tmp/foo sleep 1
tprof statistics:
sample 57
overflow 0
buf 3
emptybuf 3
dropbuf 0
dropbuf_sample 0
4. format the result.
the first line in the following example means that 11 samples have been
taken at 0xc0396c36, whose symbolic name is lapic_gettick+0x6.
# sh ./fmt.sh < /tmp/foo
11 c0396c36 lapic_gettick+0x6
5 c039b98a x86_pause+0x2
4 c010cf9d __cpu_simple_lock+0xd
2 c010cfcd __cpu_simple_lock_try+0xd
2 c039b571 bus_space_read_4+0x11
1 c01005c8 sse2_zero_page+0x18
1 c0100624 sse2_copy_page+0x34
1 c010ceeb mutex_spin_enter+0x2b
1 c010cef5 mutex_spin_enter+0x35
1 c010cf32 mutex_spin_exit+0x32
1 c0119ed0 in_localaddr+0x30
1 c012d0fd tcp_output+0x1fbd
1 c02980c2 amap_copy+0x42
1 c02a0100 uvm_map_lookup_entry_bytree+0x20
1 c02a27fe uvm_tree_RB_REMOVE+0xee
1 c02a8914 uvm_pagelookup+0x4
1 c02a9d5c uvm_pagefree+0xfc
1 c02a9e36 uvm_pagefree+0x1d6
1 c02dd4f6 lockmgr+0x3d6
1 c02dd9d1 _kernel_unlock+0xa1
1 c02e0285 mutex_vector_enter+0x15
1 c02eb83a sleepq_wake+0x5a
1 c0303467 pool_cache_get_paddr+0x97
1 c030368b pool_cache_put_slow+0x6b
1 c0321ed3 pffasttimo+0x33
1 c034547a VOP_LOCK+0xa
1 c0346235 VOP_ACCESS+0x45
1 c034a749 genfs_unlock+0x29
1 c038f251 cpu_idle+0x31
1 c03938da pmap_write_protect+0xaa
1 c0394305 pmap_do_remove+0x2e5
1 c03944b3 pmap_do_remove+0x493
1 c0396cdf lapic_delay+0x5f
1 c0396d19 lapic_delay+0x99
1 c0396d1d lapic_delay+0x9d
1 c0397429 lapic_clockintr+0x19
1 c039b984 x86_mwait+0xc
1 c042f66a _atomic_swap_32+0xa
