perfcounters.lisp

   1 ;;;; Copyright 2009 Vitaly Mayatskikh <v.mayatskih@gmail.com>
   2 ;;;;
   3 ;;;; This file is a part of CL-Perfcounters
   4 ;;;;
   5 ;;;; Performance counters are special hardware registers available on most modern
   6 ;;;; CPUs. These registers count the number of certain types of hw events: such
   7 ;;;; as instructions executed, cachemisses suffered, or branches mis-predicted -
   8 ;;;; without slowing down the kernel or applications. These registers can also
   9 ;;;; trigger interrupts when a threshold number of events have passed - and can
  10 ;;;; thus be used to profile the code that runs on that CPU.
  11 ;;;;
  12 ;;;; The Linux Performance Counter subsystem provides an abstraction of these
  13 ;;;; hardware capabilities. It provides per task and per CPU counters, counter
  14 ;;;; groups, and it provides event capabilities on top of those.  It
  15 ;;;; provides "virtual" 64-bit counters, regardless of the width of the
  16 ;;;; underlying hardware counters.
  17 ;;;;
  18 ;;;; CL-Perfcounters is free software: you can redistribute it and/or modify
  19 ;;;; it under the terms of the GNU General Public License as published by
  20 ;;;; the Free Software Foundation, either version 3 of the License, or
  21 ;;;; (at your option) any later version.
  22 ;;;;
  23 ;;;; CL-Perfcounters is distributed in the hope that it will be useful,
  24 ;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  25 ;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26 ;;;; GNU General Public License for more details.
  27 ;;;;
  28 ;;;; You should have received a copy of the GNU General Public License
  29 ;;;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
  30
  31 (defpackage :perfcounters
  32   (:use :cl :cffi)
  33   (:export :with-performance-counters :time+))
  34
  35 (in-package :perfcounters)
  36
  37 ;; x86-64: 298
  38 ;; x86:    336
  39 ;; ppc:    319
  40 ;; s390:   331
  41 (defparameter +syscall+ 298)
  42
  43 (defparameter +pr-task-perf-counters-disable+ 31)
  44 (defparameter +pr-task-perf-counters-enable+ 32)
  45
  46 (defcstruct perf-counter-attr
  47   (type                 :unsigned-int)
  48   (size                 :unsigned-int)
  49   (config               :unsigned-long-long)
  50   (sample-period/freq   :unsigned-long-long)
  51   (sample-type          :unsigned-long-long)
  52   (read_format          :unsigned-int)
  53   (flags                :unsigned-long-long)
  54   (wakeup-events        :unsigned-int)
  55   (reserved-2           :unsigned-int)
  56   (reserved-3           :unsigned-long-long))
  57
  58 (defparameter +perf-type-hardware+ 0)
  59 (defparameter +perf-type-software+ 1)
  60 (defparameter +perf-type-tracepoint+ 2)
  61 (defparameter +perf-type-hw-cache+ 3)
  62
  63 ;; Common hardware events, generalized by the kernel:
  64 (defparameter +perf-count-hw-cpu-cycles+ 0)
  65 (defparameter +perf-count-hw-instructions+ 1)
  66 (defparameter +perf-count-hw-cache-references+ 2)
  67 (defparameter +perf-count-hw-cache-misses+ 3)
  68 (defparameter +perf-count-hw-branch-instructions+ 4)
  69 (defparameter +perf-count-hw-branch-misses+ 5)
  70 (defparameter +perf-count-hw-bus-cycles+ 6)
  71
  72 ;; Special "software" counters provided by the kernel, even if the hardware
  73 ;; does not support performance counters. These counters measure various
  74 ;; physical and sw events of the kernel (and allow the profiling of them as
  75 ;; well):
  76 (defparameter +perf-count-sw-cpu-clock+ 32)
  77 (defparameter +perf-count-sw-task-clock+ 33)
  78 (defparameter +perf-count-sw-page-faults+ 34)
  79 (defparameter +perf-count-sw-context-switches+ 35)
  80 (defparameter +perf-count-sw-cpu-migrations+ 36)
  81 (defparameter +perf-count-sw-page-faults-min+ 37)
  82 (defparameter +perf-count-sw-page-faults-maj+ 38)
  83
  84 (defparameter +perf-count-hw-all+
  85   '(+perf-count-hw-cpu-cycles+ +perf-count-hw-instructions+
  86     +perf-count-hw-cache-references+ +perf-count-hw-cache-misses+
  87     +perf-count-hw-branch-instructions+ +perf-count-hw-branch-misses+
  88     +perf-count-hw-bus-cycles+))
  89
  90 (defparameter +perf-count-sw-all+
  91   '(+perf-count-sw-cpu-clock+ +perf-count-sw-task-clock+
  92     +perf-count-sw-page-faults+ +perf-count-sw-context-switches+
  93     +perf-count-sw-cpu-migrations+ +perf-count-sw-page-faults-min+
  94     +perf-count-sw-page-faults-maj+))
  95
  96 (defparameter +perf-count-all+
  97   (append +perf-count-hw-all+ +perf-count-sw-all+))
  98
  99 ;; Generalized hardware cache counters:
 100
 101 ;;       { L1-D, L1-I, LLC, ITLB, DTLB, BPU } x
 102 ;;       { read, write, prefetch } x
 103 ;;       { accesses, misses }
 104
 105 (defparameter +perf-count-hw-cache-l1d+ 0)
 106 (defparameter +perf-count-hw-cache-l1i+ 1)
 107 (defparameter +perf-count-hw-cache-ll+ 2)
 108 (defparameter +perf-count-hw-cache-dtlb+ 3)
 109 (defparameter +perf-count-hw-cache-itlb+ 4)
 110 (defparameter +perf-count-hw-cache-bpu+ 5)
 111
 112 (defparameter +perf-count-format-string+
 113   '(("~@[~:D CPU cycle~:P consumed~%~]"
 114      "~@[~:D instruction~:P executed~%~]"
 115      "~@[~:D cache hit~:P~%~]"
 116      "~@[~:D cache misses~%~]"
 117      "~@[~:D branch instruction~:P~%~]"
 118      "~@[~:D branch misses~:P~%~]"
 119      "~@[~:D bus cycle~:P~%~]")
 120     ("~@[~:D cpu clock~:P~%~]"
 121      "~@[~:D task clock~:P~%~]"
 122      "~@[~:D page fault~:P~%~]"
 123      "~@[~:D context switch~:P~%~]"
 124      "~@[~:D cpu migration~:P~%~]"
 125      "~@[~:D minor fault~%~]"
 126      "~@[~:D major fault~:P~%~]")
 127     ()
 128     ()
 129     ))
 130
 131 ;; Bits that can be set in hw_event.read_format to request that
 132 ;; reads on the counter should return the indicated quantities,
 133 ;; in increasing order of bit value, after the counter value.
 134 (defcenum perf-counter-read-format
 135   (:perf-format-total-time-enabled)
 136   (:perf-format-total-time-running))
 137
 138 ;; Bits that can be set in hw_event.record_type to request information
 139 ;; in the overflow packets.
 140 (defcenum perf-counter-record-format
 141   (:perf-record-ip 1)
 142   (:perf-record-tid 2)
 143   (:perf-record-time 4)
 144   (:perf-record-addr 8)
 145   (:perf-record-group 16)
 146   (:perf-record-callchain 32))
 147
 148 (defcfun ("syscall" %perf-counter-open) :int
 149   (syscall-nr :int)
 150   (ptr :pointer)
 151   (pid :unsigned-long)
 152   (cpu :int)
 153   (group-fd :int)
 154   (flags :unsigned-long))
 155
 156 (defcvar "errno" :int)
 157
 158 (defun fail (func)
 159   (error "~A failed: ~A" func
 160          (foreign-funcall "strerror" :int *errno* :string)))
 161
 162 (defun perf-counter-open (event-type event)
 163   (let ((attr (foreign-alloc 'perf-counter-attr)))
 164     (with-foreign-slots ((type size config flags) attr perf-counter-attr)
 165       (setf type event-type
 166             size (foreign-type-size 'perf-counter-attr)
 167             config event
 168             flags 3))
 169     (multiple-value-bind (ret)
 170         (%perf-counter-open +syscall+ attr 0 -1 -1 0)
 171       (foreign-free attr)
 172       (when (< ret 0)
 173         (fail "Syscall perf_counter_open"))
 174       ret)))
 175
 176 (defcfun ("prctl" %perf-counter-prctl) :int
 177   (option :int))
 178
 179 (defun perf-counter-prctl (opt)
 180   (multiple-value-bind (ret)
 181       (%perf-counter-prctl opt)
 182     (when (< ret 0)
 183       (fail "prctl"))
 184     ret))
 185
 186 (defun perf-counter-start ()
 187   (perf-counter-prctl +pr-task-perf-counters-enable+))
 188
 189 (defun perf-counter-stop ()
 190   (perf-counter-prctl +pr-task-perf-counters-disable+))
 191
 192 (defcfun ("read" %read) :unsigned-long
 193   (fd :int)
 194   (buf :pointer)
 195   (count :unsigned-long))
 196
 197 (defun perf-counter-read (fd)
 198   (with-foreign-object (counter :unsigned-long)
 199     (multiple-value-bind (ret)
 200         (%read fd counter (foreign-type-size :unsigned-long))
 201       (when (< ret (foreign-type-size :unsigned-long))
 202         (fail "perf-counter-read")))
 203     (mem-ref counter :unsigned-long)))
 204
 205 (defcfun ("close" %perf-counter-close) :int
 206   (fd :int))
 207
 208 (defun perf-counter-close (fd)
 209   (multiple-value-bind (ret)
 210       (%perf-counter-close fd)
 211     (when (< ret 0)
 212       (fail "perf-cunter-close"))
 213     ret))
 214
 215 (defmacro with-performance-counters (cntrs &body body)
 216   (let ((counters (gensym))
 217         (sym (car cntrs)))
 218     (when (symbolp sym)
 219       (case sym
 220         (:perf-count-hw-all (setq cntrs +perf-count-hw-all+))
 221         (:perf-count-sw-all (setq cntrs +perf-count-sw-all+))
 222         (:perf-count-all (setq cntrs +perf-count-all+))))
 223     `(let ((,counters ',cntrs))
 224        (loop for i in ,counters
 225           for j = (or (and (symbolp i) (symbol-value i)) i)
 226           for (type . counter) = (if (< j 32)
 227                                    (cons +perf-type-hardware+ j)
 228                                    (cons +perf-type-software+ (- j 32)))
 229           collect
 230             (perf-counter-open
 231              type
 232              counter)
 233           into descriptors
 234           collect
 235             (nth counter (nth type +perf-count-format-string+))
 236           into formats
 237           finally
 238             (progn
 239               (perf-counter-start)
 240               ,@body
 241               (perf-counter-stop)
 242               (apply #'format *trace-output*
 243                      (format nil "~A~{ ~A~}~A"
 244                              "~&Performance monitor:~%~@<~@;" formats "~:>")
 245                      (loop for counter in descriptors
 246                         collect (perf-counter-read counter)
 247                         do (perf-counter-close counter))))))))
 248
 249 (defmacro time+ (&body body)
 250   `(with-performance-counters (:perf-count-hw-all)
 251      ,@body))
 252
 253 ;; (time+ t)
 254
 255 ;; (with-performance-counters (+perf-count-hw-cpu-cycles+
 256 ;;                          +perf-count-hw-cache-references+
 257 ;;                          +perf-count-sw-context-switches+)
 258 ;;   (sleep 1))