Merge pull request #4 from YingboMa/myb/perf_macro

Nicer example in the README

Author: vchuravy

README.md

@@ -5,70 +5,49 @@ the kernel multiplexes event counter that requires limited hardware resources so
 if you need to compare two quantities you must put them in the same event group so they are always scheduled at the same time (or not at all).
 
 ```julia
-julia> import LinuxPerf: make_bench, enable!, disable!, reset!, reasonable_defaults, counters
-julia> const bench = make_bench(reasonable_defaults);
+julia> using LinuxPerf
+
 julia> @noinline function g(a)
-           enable!(bench)
            c = 0
            for x in a
                if x > 0
                    c += 1
                end
            end
-           disable!(bench)
            c
        end
 g (generic function with 1 method)
+
 julia> g(zeros(10000))
 0
-julia> counters(bench)
-hw:cycles : 
-	               52794 (100.0 %)
-hw:cache_access : 
-	                 881 (100.0 %)
-hw:cache_misses : 
-	                 579 (100.0 %)
-hw:branches : 
-	               31367 (100.0 %)
-hw:branch_mispredicts : 
-	                 107 (100.0 %)      # =)
-hw:instructions : 
-	               96961 (100.0 %)
-sw:ctx_switches : 
-	                   0 (100.0 %)
-sw:page_faults : 
-	                   0 (100.0 %)
-sw:minor_page_faults : 
-	                   0 (100.0 %)
-sw:major_page_faults : 
-	                   0 (100.0 %)
-sw:cpu_migrations : 
-	                   0 (100.0 %)
 
-julia> reset!(bench)
-julia> g(randn(10000))
-5023
-julia> counters(bench)
-hw:cycles : 
-	              194454 (100.0 %)
-hw:cache_access : 
-	                 291 (100.0 %)
-hw:cache_misses : 
-	                 222 (100.0 %)
-hw:branches : 
-	               38050 (100.0 %)
-hw:branch_mispredicts : 
-	                5131 (100.0 %)      # =(
-hw:instructions : 
-	              129253 (100.0 %)
-sw:ctx_switches : 
-	                   0 (100.0 %)
-sw:page_faults : 
-	                   0 (100.0 %)
-sw:minor_page_faults : 
-	                   0 (100.0 %)
-sw:major_page_faults : 
-	                   0 (100.0 %)
-sw:cpu_migrations : 
-	                   0 (100.0 %)
+julia> data = zeros(10000); @measure g(data)
+┌───────────────────────┬────────────┬─────────────┐
+│                       │ Events     │ Active Time │
+├───────────────────────┼────────────┼─────────────┤
+│             hw:cycles │ 25,583,165 │ 100.0 %     │
+├───────────────────────┼────────────┼─────────────┤
+│       hw:cache_access │ 1,640,429  │ 100.0 %     │
+├───────────────────────┼────────────┼─────────────┤
+│       hw:cache_misses │ 328,561    │ 100.0 %     │
+├───────────────────────┼────────────┼─────────────┤
+│           hw:branches │ 6,164,138  │ 100.0 %     │
+├───────────────────────┼────────────┼─────────────┤
+│ hw:branch_mispredicts │ 223,272    │ 100.0 %     │
+├───────────────────────┼────────────┼─────────────┤
+│       hw:instructions │ 28,115,285 │ 100.0 %     │
+├───────────────────────┼────────────┼─────────────┤
+│       sw:ctx_switches │ 0          │ 100.0 %     │
+├───────────────────────┼────────────┼─────────────┤
+│        sw:page_faults │ 41         │ 100.0 %     │
+├───────────────────────┼────────────┼─────────────┤
+│  sw:minor_page_faults │ 41         │ 100.0 %     │
+├───────────────────────┼────────────┼─────────────┤
+│  sw:major_page_faults │ 0          │ 100.0 %     │
+├───────────────────────┼────────────┼─────────────┤
+│     sw:cpu_migrations │ 0          │ 100.0 %     │
+└───────────────────────┴────────────┴─────────────┘
 ```
+
+For more fine tuned performance profile examples, please check out the `test`
+directory.