src/jit/p.lua

   1 ----------------------------------------------------------------------------
   2 -- LuaJIT profiler.
   3 --
   4 -- Copyright (C) 2005-2013 Mike Pall. All rights reserved.
   5 -- Released under the MIT license. See Copyright Notice in luajit.h
   6 ----------------------------------------------------------------------------
   7 --
   8 -- This module is a simple command line interface to the built-in
   9 -- low-overhead profiler of LuaJIT.
  10 --
  11 -- The lower-level API of the profiler is accessible via the "jit.profile"
  12 -- module or the luaJIT_profile_* C API.
  13 --
  14 -- Example usage:
  15 --
  16 --   luajit -jp myapp.lua
  17 --   luajit -jp=s myapp.lua
  18 --   luajit -jp=-s myapp.lua
  19 --   luajit -jp=vl myapp.lua
  20 --   luajit -jp=G,profile.txt myapp.lua
  21 --
  22 -- The following dump features are available:
  23 --
  24 --   f  Stack dump: function name, otherwise module:line. Default mode.
  25 --   F  Stack dump: ditto, but always prepend module.
  26 --   l  Stack dump: module:line.
  27 --   <number> stack dump depth (callee < caller). Default: 1.
  28 --   -<number> Inverse stack dump depth (caller > callee).
  29 --   s  Split stack dump after first stack level. Implies abs(depth) >= 2.
  30 --   p  Show full path for module names.
  31 --   v  Show VM states. Can be combined with stack dumps, e.g. vf or fv.
  32 --   z  Show zones. Can be combined with stack dumps, e.g. zf or fz.
  33 --   r  Show raw sample counts. Default: show percentages.
  34 --   a  Annotate excerpts from source code files.
  35 --   A  Annotate complete source code files.
  36 --   G  Produce raw output suitable for graphical tools (e.g. flame graphs).
  37 --   m<number> Minimum sample percentage to be shown. Default: 3.
  38 --   i<number> Sampling interval in milliseconds. Default: 10.
  39 --
  40 ----------------------------------------------------------------------------
  41
  42 -- Cache some library functions and objects.
  43 local jit = require("jit")
  44 assert(jit.version_num == 20100, "LuaJIT core/library version mismatch")
  45 local profile = require("jit.profile")
  46 local vmdef = require("jit.vmdef")
  47 local math = math
  48 local pairs, ipairs, tonumber, floor = pairs, ipairs, tonumber, math.floor
  49 local sort, format = table.sort, string.format
  50 local stdout = io.stdout
  51 local zone -- Load jit.zone module on demand.
  52
  53 -- Output file handle.
  54 local out
  55
  56 ------------------------------------------------------------------------------
  57
  58 local prof_ud
  59 local prof_states, prof_split, prof_min, prof_raw, prof_fmt, prof_depth
  60 local prof_ann, prof_count1, prof_count2, prof_samples
  61
  62 local map_vmmode = {
  63   N = "Compiled",
  64   I = "Interpreted",
  65   C = "C code",
  66   G = "Garbage Collector",
  67   J = "JIT Compiler",
  68 }
  69
  70 -- Profiler callback.
  71 local function prof_cb(th, samples, vmmode)
  72   prof_samples = prof_samples + samples
  73   local key_stack, key_stack2, key_state
  74   -- Collect keys for sample.
  75   if prof_states then
  76     if prof_states == "v" then
  77       key_state = map_vmmode[vmmode] or vmmode
  78     else
  79       key_state = zone:get() or "(none)"
  80     end
  81   end
  82   if prof_fmt then
  83     key_stack = profile.dumpstack(th, prof_fmt, prof_depth)
  84     key_stack = key_stack:gsub("%[builtin#(%d+)%]", function(x)
  85       return vmdef.ffnames[tonumber(x)]
  86     end)
  87     if prof_split == 2 then
  88       local k1, k2 = key_stack:match("(.-) [<>] (.*)")
  89       if k2 then key_stack, key_stack2 = k1, k2 end
  90     elseif prof_split == 3 then
  91       key_stack2 = profile.dumpstack(th, "l", 1)
  92     end
  93   end
  94   -- Order keys.
  95   local k1, k2
  96   if prof_split == 1 then
  97     if key_state then
  98       k1 = key_state
  99       if key_stack then k2 = key_stack end
 100     end
 101   elseif key_stack then
 102     k1 = key_stack
 103     if key_stack2 then k2 = key_stack2 elseif key_state then k2 = key_state end
 104   end
 105   -- Coalesce samples in one or two levels.
 106   if k1 then
 107     local t1 = prof_count1
 108     t1[k1] = (t1[k1] or 0) + samples
 109     if k2 then
 110       local t2 = prof_count2
 111       local t3 = t2[k1]
 112       if not t3 then t3 = {}; t2[k1] = t3 end
 113       t3[k2] = (t3[k2] or 0) + samples
 114     end
 115   end
 116 end
 117
 118 ------------------------------------------------------------------------------
 119
 120 -- Show top N list.
 121 local function prof_top(count1, count2, samples, indent)
 122   local t, n = {}, 0
 123   for k, v in pairs(count1) do
 124     n = n + 1
 125     t[n] = k
 126   end
 127   sort(t, function(a, b) return count1[a] > count1[b] end)
 128   for i=1,n do
 129     local k = t[i]
 130     local v = count1[k]
 131     local pct = floor(v*100/samples + 0.5)
 132     if pct < prof_min then break end
 133     if not prof_raw then
 134       out:write(format("%s%2d%%  %s\n", indent, pct, k))
 135     elseif prof_raw == "r" then
 136       out:write(format("%s%5d  %s\n", indent, v, k))
 137     else
 138       out:write(format("%s %d\n", k, v))
 139     end
 140     if count2 then
 141       local r = count2[k]
 142       if r then
 143         prof_top(r, nil, v, (prof_split == 3 or prof_split == 1) and "  -- " or
 144                             (prof_depth < 0 and "  -> " or "  <- "))
 145       end
 146     end
 147   end
 148 end
 149
 150 -- Annotate source code
 151 local function prof_annotate(count1, samples)
 152   local files = {}
 153   local ms = 0
 154   for k, v in pairs(count1) do
 155     local pct = floor(v*100/samples + 0.5)
 156     ms = math.max(ms, v)
 157     if pct >= prof_min then
 158       local file, line = k:match("^(.*):(%d+)$")
 159       local fl = files[file]
 160       if not fl then fl = {}; files[file] = fl; files[#files+1] = file end
 161       line = tonumber(line)
 162       fl[line] = prof_raw and v or pct
 163     end
 164   end
 165   sort(files)
 166   local fmtv, fmtn = " %3d%% | %s\n", "      | %s\n"
 167   if prof_raw then
 168     local n = math.max(5, math.ceil(math.log10(ms)))
 169     fmtv = "%"..n.."d | %s\n"
 170     fmtn = (" "):rep(n).." | %s\n"
 171   end
 172   local ann = prof_ann
 173   for _, file in ipairs(files) do
 174     local f0 = file:byte()
 175     if f0 == 40 or f0 == 91 then
 176       out:write(format("\n====== %s ======\n[Cannot annotate non-file]\n", file))
 177       break
 178     end
 179     local fp, err = io.open(file)
 180     if not fp then
 181       out:write(format("====== ERROR: %s: %s\n", file, err))
 182       break
 183     end
 184     out:write(format("\n====== %s ======\n", file))
 185     local fl = files[file]
 186     local n, show = 1, false
 187     if ann ~= 0 then
 188       for i=1,ann do
 189         if fl[i] then show = true; out:write("@@ 1 @@\n"); break end
 190       end
 191     end
 192     for line in fp:lines() do
 193       if line:byte() == 27 then
 194         out:write("[Cannot annotate bytecode file]\n")
 195         break
 196       end
 197       local v = fl[n]
 198       if ann ~= 0 then
 199         local v2 = fl[n+ann]
 200         if show then
 201           if v2 then show = n+ann elseif v then show = n
 202           elseif show+ann < n then show = false end
 203         elseif v2 then
 204           show = n+ann
 205           out:write(format("@@ %d @@\n", n))
 206         end
 207         if not show then goto next end
 208       end
 209       if v then
 210         out:write(format(fmtv, v, line))
 211       else
 212         out:write(format(fmtn, line))
 213       end
 214     ::next::
 215       n = n + 1
 216     end
 217     fp:close()
 218   end
 219 end
 220
 221 ------------------------------------------------------------------------------
 222
 223 -- Finish profiling and dump result.
 224 local function prof_finish()
 225   if prof_ud then
 226     profile.stop()
 227     local samples = prof_samples
 228     if samples == 0 then
 229       if prof_raw ~= true then out:write("[No samples collected]\n") end
 230       return
 231     end
 232     if prof_ann then
 233       prof_annotate(prof_count1, samples)
 234     else
 235       prof_top(prof_count1, prof_count2, samples, "")
 236     end
 237     prof_count1 = nil
 238     prof_count2 = nil
 239     prof_ud = nil
 240   end
 241 end
 242
 243 -- Start profiling.
 244 local function prof_start(mode)
 245   local interval = ""
 246   mode = mode:gsub("i%d*", function(s) interval = s; return "" end)
 247   prof_min = 3
 248   mode = mode:gsub("m(%d+)", function(s) prof_min = tonumber(s); return "" end)
 249   prof_depth = 1
 250   mode = mode:gsub("%-?%d+", function(s) prof_depth = tonumber(s); return "" end)
 251   local m = {}
 252   for c in mode:gmatch(".") do m[c] = c end
 253   prof_states = m.z or m.v
 254   if prof_states == "z" then zone = require("jit.zone") end
 255   local scope = m.l or m.f or m.F or (prof_states and "" or "f")
 256   local flags = (m.p or "")
 257   prof_raw = m.r
 258   if m.s then
 259     prof_split = 2
 260     if prof_depth == -1 or m["-"] then prof_depth = -2
 261     elseif prof_depth == 1 then prof_depth = 2 end
 262   elseif mode:find("[fF].*l") then
 263     scope = "l"
 264     prof_split = 3
 265   else
 266     prof_split = (scope == "" or mode:find("[zv].*[lfF]")) and 1 or 0
 267   end
 268   prof_ann = m.A and 0 or (m.a and 3)
 269   if prof_ann then
 270     scope = "l"
 271     prof_fmt = "pl"
 272     prof_split = 0
 273     prof_depth = 1
 274   elseif m.G and scope ~= "" then
 275     prof_fmt = flags..scope.."Z;"
 276     prof_depth = -100
 277     prof_raw = true
 278     prof_min = 0
 279   elseif scope == "" then
 280     prof_fmt = false
 281   else
 282     local sc = prof_split == 3 and m.f or m.F or scope
 283     prof_fmt = flags..sc..(prof_depth >= 0 and "Z < " or "Z > ")
 284   end
 285   prof_count1 = {}
 286   prof_count2 = {}
 287   prof_samples = 0
 288   profile.start(scope:lower()..interval, prof_cb)
 289   prof_ud = newproxy(true)
 290   getmetatable(prof_ud).__gc = prof_finish
 291 end
 292
 293 ------------------------------------------------------------------------------
 294
 295 local function start(mode, outfile)
 296   if not outfile then outfile = os.getenv("LUAJIT_PROFILEFILE") end
 297   if outfile then
 298     out = outfile == "-" and stdout or assert(io.open(outfile, "w"))
 299   else
 300     out = stdout
 301   end
 302   prof_start(mode or "f")
 303 end
 304
 305 -- Public module functions.
 306 return {
 307   start = start, -- For -j command line option.
 308   stop = prof_finish
 309 }
 310