perf record: Enable arbitrary event names thru name= modifier

Enable complex event names containing [.:=,] symbols to be encoded into Perf
trace using name= modifier e.g. like this:

  perf record -e cpu/name=\'OFFCORE_RESPONSE:request=DEMAND_RFO:response=L3_HIT.SNOOP_HITM\',\
		  period=0x3567e0,event=0x3c,cmask=0x1/Duk ./futex

Below is how it looks like in the report output. Please note explicit escaped
quoting at cmdline string in the header so that thestring can be directly reused
for another collection in shell:

perf report --header

  # ========
  ...
  # cmdline : /root/abudanko/kernel/tip/tools/perf/perf record -v -e cpu/name=\'OFFCORE_RESPONSE:request=DEMAND_RFO:response=L3_HIT.SNOOP_HITM\',period=0x3567e0,event=0x3c,cmask=0x1/Duk ./futex
  # event : name = OFFCORE_RESPONSE:request=DEMAND_RFO:response=L3_HIT.SNOOP_HITM, , type = 4, size = 112, config = 0x100003c, { sample_period, sample_freq } = 3500000, sample_type = IP|TID|TIME, disabled = 1, inh
  ...
  # ========
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 24K of event 'OFFCORE_RESPONSE:request=DEMAND_RFO:response=L3_HIT.SNOOP_HITM'
  # Event count (approx.): 86492000000
  #
  # Overhead  Command  Shared Object     Symbol
  # ........  .......  ................  ..............................................
  #
      14.75%  futex    [kernel.vmlinux]  [k] __entry_trampoline_start
...

  perf stat -e cpu/name=\'CPU_CLK_UNHALTED.THREAD:cmask=0x1\',period=0x3567e0,event=0x3c,cmask=0x1/Duk ./futex

  10000000 process context switches in 16678890291ns (1667.9ns/ctxsw)

   Performance counter stats for './futex':

      88,095,770,571      CPU_CLK_UNHALTED.THREAD:cmask=0x1

        16.679542407 seconds time elapsed

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/c194b060-761d-0d50-3b21-bb4ed680002d@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Documentation/perf-list.txt

@@ -124,7 +124,11 @@ The available PMUs and their raw parameters can be listed with
 For example the raw event "LSD.UOPS" core pmu event above could
 be specified as
 
-  perf stat -e cpu/event=0xa8,umask=0x1,name=LSD.UOPS_CYCLES,cmask=1/ ...
+  perf stat -e cpu/event=0xa8,umask=0x1,name=LSD.UOPS_CYCLES,cmask=0x1/ ...
+
+  or using extended name syntax
+
+  perf stat -e cpu/event=0xa8,umask=0x1,cmask=0x1,name=\'LSD.UOPS_CYCLES:cmask=0x1\'/ ...
 
 PER SOCKET PMUS
 ---------------

tools/perf/Documentation/perf-record.txt

@@ -57,6 +57,9 @@ OPTIONS
 			 FP mode, "dwarf" for DWARF mode, "lbr" for LBR mode and
 			 "no" for disable callgraph.
 	  - 'stack-size': user stack size for dwarf mode
+	  - 'name' : User defined event name. Single quotes (') may be used to
+		    escape symbols in the name from parsing by shell and tool
+		    like this: name=\'CPU_CLK_UNHALTED.THREAD:cmask=0x1\'.
 
           See the linkperf:perf-list[1] man page for more parameters.
 

tools/perf/util/header.c

@@ -1459,8 +1459,24 @@ static void print_cmdline(struct feat_fd *ff, FILE *fp)
 
 	fprintf(fp, "# cmdline : ");
 
-	for (i = 0; i < nr; i++)
+	for (i = 0; i < nr; i++) {
+		char *argv_i = strdup(ff->ph->env.cmdline_argv[i]);
+		if (!argv_i) {
 			fprintf(fp, "%s ", ff->ph->env.cmdline_argv[i]);
+		} else {
+			char *mem = argv_i;
+			do {
+				char *quote = strchr(argv_i, '\'');
+				if (!quote)
+					break;
+				*quote++ = '\0';
+				fprintf(fp, "%s\\\'", argv_i);
+				argv_i = quote;
+			} while (1);
+			fprintf(fp, "%s ", argv_i);
+			free(mem);
+		}
+	}
 	fputc('\n', fp);
 }
 

tools/perf/util/parse-events.l

@@ -53,7 +53,21 @@ static int str(yyscan_t scanner, int token)
 	YYSTYPE *yylval = parse_events_get_lval(scanner);
 	char *text = parse_events_get_text(scanner);
 
+	if (text[0] != '\'') {
 		yylval->str = strdup(text);
+	} else {
+		/*
+		 * If a text tag specified on the command line
+		 * contains opening single quite ' then it is
+		 * expected that the tag ends with single quote
+		 * as well, like this:
+		 *     name=\'CPU_CLK_UNHALTED.THREAD:cmask=1\'
+		 * quotes need to be escaped to bypass shell
+		 * processing.
+		 */
+		yylval->str = strndup(&text[1], strlen(text) - 2);
+	}
+
 	return token;
 }
 
@@ -176,6 +190,7 @@ num_dec		[0-9]+
 num_hex		0x[a-fA-F0-9]+
 num_raw_hex	[a-fA-F0-9]+
 name		[a-zA-Z_*?\[\]][a-zA-Z0-9_*?.\[\]]*
+name_tag	[\'][a-zA-Z_*?\[\]][a-zA-Z0-9_*?\-,\.\[\]:=]*[\']
 name_minus	[a-zA-Z_*?][a-zA-Z0-9\-_*?.:]*
 drv_cfg_term	[a-zA-Z0-9_\.]+(=[a-zA-Z0-9_*?\.:]+)?
 /* If you add a modifier you need to update check_modifier() */
@@ -344,6 +359,7 @@ r{num_raw_hex}		{ return raw(yyscanner); }
 {bpf_object}		{ if (!isbpf(yyscanner)) { USER_REJECT }; return str(yyscanner, PE_BPF_OBJECT); }
 {bpf_source}		{ if (!isbpf(yyscanner)) { USER_REJECT }; return str(yyscanner, PE_BPF_SOURCE); }
 {name}			{ return pmu_str_check(yyscanner); }
+{name_tag}		{ return str(yyscanner, PE_NAME); }
 "/"			{ BEGIN(config); return '/'; }
 -			{ return '-'; }
 ,			{ BEGIN(event); return ','; }