perf tools: Enable indices setting syntax for BPF map
authorWang Nan <wangnan0@huawei.com>
Mon, 22 Feb 2016 09:10:35 +0000 (09:10 +0000)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Mon, 22 Feb 2016 15:59:49 +0000 (12:59 -0300)
This patch introduces a new syntax to perf event parser:

 # perf record -e './test_bpf_map_3.c/map:channel.value[0,1,2,3...5]=101/' usleep 2

By utilizing the basic facilities in bpf-loader.c which allow setting
different slots in a BPF map separately, the newly introduced syntax
allows perf to control specific elements in a BPF map.

Test result:

  # cat ./test_bpf_map_3.c
  /************************ BEGIN **************************/
  #include <uapi/linux/bpf.h>
  #define SEC(NAME) __attribute__((section(NAME), used))
  struct bpf_map_def {
unsigned int type;
unsigned int key_size;
unsigned int value_size;
unsigned int max_entries;
  };
  static void *(*map_lookup_elem)(struct bpf_map_def *, void *) =
  (void *)BPF_FUNC_map_lookup_elem;
  static int (*trace_printk)(const char *fmt, int fmt_size, ...) =
  (void *)BPF_FUNC_trace_printk;
  struct bpf_map_def SEC("maps") channel = {
  .type = BPF_MAP_TYPE_ARRAY,
  .key_size = sizeof(int),
  .value_size = sizeof(unsigned char),
  .max_entries = 100,
  };
  SEC("func=hrtimer_nanosleep rqtp->tv_nsec")
  int func(void *ctx, int err, long nsec)
  {
  char fmt[] = "%ld\n";
  long usec = nsec * 0x10624dd3 >> 38; // nsec / 1000
  int key = (int)usec;
  unsigned char *pval = map_lookup_elem(&channel, &key);

  if (!pval)
  return 0;
  trace_printk(fmt, sizeof(fmt), (unsigned char)*pval);
  return 0;
  }
  char _license[] SEC("license") = "GPL";
  int _version SEC("version") = LINUX_VERSION_CODE;
  /************************* END ***************************/

Normal case:

  # echo "" > /sys/kernel/debug/tracing/trace
  # ./perf record -e './test_bpf_map_3.c/map:channel.value[0,1,2,3...5]=101/' usleep 2
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.012 MB perf.data ]
  # cat /sys/kernel/debug/tracing/trace | grep usleep
            usleep-405   [004] d... 2745423.547822: : 101
  # ./perf record -e './test_bpf_map_3.c/map:channel.value[0...9,20...29]=102,map:channel.value[10...19]=103/' usleep 3
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.012 MB perf.data ]
  # ./perf record -e './test_bpf_map_3.c/map:channel.value[0...9,20...29]=102,map:channel.value[10...19]=103/' usleep 15
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.012 MB perf.data ]
  # cat /sys/kernel/debug/tracing/trace | grep usleep
            usleep-405   [004] d... 2745423.547822: : 101
            usleep-655   [006] d... 2745434.122814: : 102
            usleep-904   [006] d... 2745439.916264: : 103
  # ./perf record -e './test_bpf_map_3.c/map:channel.value[all]=104/' usleep 99
  # cat /sys/kernel/debug/tracing/trace | grep usleep
            usleep-405   [004] d... 2745423.547822: : 101
            usleep-655   [006] d... 2745434.122814: : 102
            usleep-904   [006] d... 2745439.916264: : 103
            usleep-1537  [003] d... 2745538.053737: : 104

Error case:

  # ./perf record -e './test_bpf_map_3.c/map:channel.value[10...1000]=104/' usleep 99
  event syntax error: '..annel.value[10...1000]=104/'
                                   \___ Index too large
  Hint: Valid config terms:
       map:[<arraymap>].value<indices>=[value]
       map:[<eventmap>].event<indices>=[event]

       where <indices> is something like [0,3...5] or [all]
       (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Cody P Schafer <dev@codyps.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jeremie Galarneau <jeremie.galarneau@efficios.com>
Cc: Kirill Smelkov <kirr@nexedi.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1456132275-98875-9-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/util/parse-events.c
tools/perf/util/parse-events.l
tools/perf/util/parse-events.y

index 697d3506c584c23315f560772321f5c31a117941..6e2f20334379b6ef384a6fed02131348c427620a 100644 (file)
@@ -704,9 +704,10 @@ parse_events_config_bpf(struct parse_events_evlist *data,
                                                 sizeof(errbuf));
                        data->error->help = strdup(
 "Hint:\tValid config terms:\n"
-"     \tmap:[<arraymap>].value=[value]\n"
-"     \tmap:[<eventmap>].event=[event]\n"
+"     \tmap:[<arraymap>].value<indices>=[value]\n"
+"     \tmap:[<eventmap>].event<indices>=[event]\n"
 "\n"
+"     \twhere <indices> is something like [0,3...5] or [all]\n"
 "     \t(add -v to see detail)");
                        data->error->str = strdup(errbuf);
                        if (err == -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE)
index 0cc6b84a740a836555901a554d64941fa96c89bb..fb85d0311d28f3a714e0b106751e558dae1c04f1 100644 (file)
@@ -9,8 +9,8 @@
 %{
 #include <errno.h>
 #include "../perf.h"
-#include "parse-events-bison.h"
 #include "parse-events.h"
+#include "parse-events-bison.h"
 
 char *parse_events_get_text(yyscan_t yyscanner);
 YYSTYPE *parse_events_get_lval(yyscan_t yyscanner);
@@ -111,6 +111,7 @@ do {                                                        \
 %x mem
 %s config
 %x event
+%x array
 
 group          [^,{}/]*[{][^}]*[}][^,{}/]*
 event_pmu      [^,{}/]+[/][^/]*[/][^,{}/]*
@@ -176,6 +177,14 @@ modifier_bp        [rwx]{1,3}
 
 }
 
+<array>{
+"]"                    { BEGIN(config); return ']'; }
+{num_dec}              { return value(yyscanner, 10); }
+{num_hex}              { return value(yyscanner, 16); }
+,                      { return ','; }
+"\.\.\."               { return PE_ARRAY_RANGE; }
+}
+
 <config>{
        /*
         * Please update config_term_names when new static term is added.
@@ -195,6 +204,8 @@ no-inherit          { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_NOINHERIT); }
 ,                      { return ','; }
 "/"                    { BEGIN(INITIAL); return '/'; }
 {name_minus}           { return str(yyscanner, PE_NAME); }
+\[all\]                        { return PE_ARRAY_ALL; }
+"["                    { BEGIN(array); return '['; }
 }
 
 <mem>{
index 0e2d433e4ffa71c99071895abb0f85fc5f64311a..d1fbcabbe70d746d542c33e2c447a05b0b6955ee 100644 (file)
@@ -48,6 +48,7 @@ static inc_group_count(struct list_head *list,
 %token PE_PREFIX_MEM PE_PREFIX_RAW PE_PREFIX_GROUP
 %token PE_ERROR
 %token PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT
+%token PE_ARRAY_ALL PE_ARRAY_RANGE
 %type <num> PE_VALUE
 %type <num> PE_VALUE_SYM_HW
 %type <num> PE_VALUE_SYM_SW
@@ -83,6 +84,9 @@ static inc_group_count(struct list_head *list,
 %type <head> group_def
 %type <head> group
 %type <head> groups
+%type <array> array
+%type <array> array_term
+%type <array> array_terms
 
 %union
 {
@@ -94,6 +98,7 @@ static inc_group_count(struct list_head *list,
                char *sys;
                char *event;
        } tracepoint_name;
+       struct parse_events_array array;
 }
 %%
 
@@ -572,6 +577,86 @@ PE_TERM
        ABORT_ON(parse_events_term__num(&term, (int)$1, NULL, 1, &@1, NULL));
        $$ = term;
 }
+|
+PE_NAME array '=' PE_NAME
+{
+       struct parse_events_term *term;
+       int i;
+
+       ABORT_ON(parse_events_term__str(&term, PARSE_EVENTS__TERM_TYPE_USER,
+                                       $1, $4, &@1, &@4));
+
+       term->array = $2;
+       $$ = term;
+}
+|
+PE_NAME array '=' PE_VALUE
+{
+       struct parse_events_term *term;
+
+       ABORT_ON(parse_events_term__num(&term, PARSE_EVENTS__TERM_TYPE_USER,
+                                       $1, $4, &@1, &@4));
+       term->array = $2;
+       $$ = term;
+}
+
+array:
+'[' array_terms ']'
+{
+       $$ = $2;
+}
+|
+PE_ARRAY_ALL
+{
+       $$.nr_ranges = 0;
+       $$.ranges = NULL;
+}
+
+array_terms:
+array_terms ',' array_term
+{
+       struct parse_events_array new_array;
+
+       new_array.nr_ranges = $1.nr_ranges + $3.nr_ranges;
+       new_array.ranges = malloc(sizeof(new_array.ranges[0]) *
+                                 new_array.nr_ranges);
+       ABORT_ON(!new_array.ranges);
+       memcpy(&new_array.ranges[0], $1.ranges,
+              $1.nr_ranges * sizeof(new_array.ranges[0]));
+       memcpy(&new_array.ranges[$1.nr_ranges], $3.ranges,
+              $3.nr_ranges * sizeof(new_array.ranges[0]));
+       free($1.ranges);
+       free($3.ranges);
+       $$ = new_array;
+}
+|
+array_term
+
+array_term:
+PE_VALUE
+{
+       struct parse_events_array array;
+
+       array.nr_ranges = 1;
+       array.ranges = malloc(sizeof(array.ranges[0]));
+       ABORT_ON(!array.ranges);
+       array.ranges[0].start = $1;
+       array.ranges[0].length = 1;
+       $$ = array;
+}
+|
+PE_VALUE PE_ARRAY_RANGE PE_VALUE
+{
+       struct parse_events_array array;
+
+       ABORT_ON($3 < $1);
+       array.nr_ranges = 1;
+       array.ranges = malloc(sizeof(array.ranges[0]));
+       ABORT_ON(!array.ranges);
+       array.ranges[0].start = $1;
+       array.ranges[0].length = $3 - $1 + 1;
+       $$ = array;
+}
 
 sep_dc: ':' |