perf tools: Per event max-stack settings

The tooling counterpart, now it is possible to do:

  # perf record -e sched:sched_switch/max-stack=10/ -e cycles/call-graph=dwarf,max-stack=4/ -e cpu-cycles/call-graph=dwarf,max-stack=1024/ usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.052 MB perf.data (5 samples) ]
  # perf evlist -v
  sched:sched_switch: type: 2, size: 112, config: 0x110, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CALLCHAIN|CPU|PERIOD|RAW|IDENTIFIER, read_format: ID, disabled: 1, inherit: 1, mmap: 1, comm: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, sample_max_stack: 10
  cycles/call-graph=dwarf,max-stack=4/: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CALLCHAIN|PERIOD|REGS_USER|STACK_USER|IDENTIFIER, read_format: ID, disabled: 1, inherit: 1, freq: 1, enable_on_exec: 1, sample_id_all: 1, exclude_guest: 1, exclude_callchain_user: 1, sample_regs_user: 0xff0fff, sample_stack_user: 8192, sample_max_stack: 4
  cpu-cycles/call-graph=dwarf,max-stack=1024/: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CALLCHAIN|PERIOD|REGS_USER|STACK_USER|IDENTIFIER, read_format: ID, disabled: 1, inherit: 1, freq: 1, enable_on_exec: 1, sample_id_all: 1, exclude_guest: 1, exclude_callchain_user: 1, sample_regs_user: 0xff0fff, sample_stack_user: 8192, sample_max_stack: 1024
  # Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events

Using just /max-stack=N/ means /call-graph=fp,max-stack=N/, that should
be further configurable by means of some .perfconfig knob.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/n/tip-kolmn1yo40p7jhswxwrc7rrd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

7 files changed, 29 insertions, 2 deletions

diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index 65e2a4f7cb4e..a70f6b54eb92 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -94,6 +94,7 @@ struct callchain_param {
         enum perf_call_graph_mode record_mode;
         u32                     dump_size;
         enum chain_mode         mode;
+        u16                     max_stack;
         u32                     print_limit;
         double                  min_percent;
         sort_chain_func_t       sort;
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 02c177d14c8d..245ac503f211 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -572,6 +572,8 @@ void perf_evsel__config_callchain(struct perf_evsel *evsel,
 
         perf_evsel__set_sample_bit(evsel, CALLCHAIN);
 
+        attr->sample_max_stack = param->max_stack;
+
         if (param->record_mode == CALLCHAIN_LBR) {
                 if (!opts->branch_stack) {
                         if (attr->exclude_user) {
@@ -635,7 +637,8 @@ static void apply_config_terms(struct perf_evsel *evsel,
         struct perf_event_attr *attr = &evsel->attr;
         struct callchain_param param;
         u32 dump_size = 0;
-        char *callgraph_buf = NULL;
+        int max_stack = 0;
+        const char *callgraph_buf = NULL;
 
         /* callgraph default */
         param.record_mode = callchain_param.record_mode;
@@ -662,6 +665,9 @@ static void apply_config_terms(struct perf_evsel *evsel,
                 case PERF_EVSEL__CONFIG_TERM_STACK_USER:
                         dump_size = term->val.stack_user;
                         break;
+                case PERF_EVSEL__CONFIG_TERM_MAX_STACK:
+                        max_stack = term->val.max_stack;
+                        break;
                 case PERF_EVSEL__CONFIG_TERM_INHERIT:
                         /*
                          * attr->inherit should has already been set by
@@ -677,7 +683,12 @@ static void apply_config_terms(struct perf_evsel *evsel,
         }
 
         /* User explicitly set per-event callgraph, clear the old setting and reset. */
-        if ((callgraph_buf != NULL) || (dump_size > 0)) {
+        if ((callgraph_buf != NULL) || (dump_size > 0) || max_stack) {
+                if (max_stack) {
+                        param.max_stack = max_stack;
+                        if (callgraph_buf == NULL)
+                                callgraph_buf = "fp";
+                }
 
                 /* parse callgraph parameters */
                 if (callgraph_buf != NULL) {
@@ -1329,6 +1340,7 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
         PRINT_ATTRf(clockid, p_signed);
         PRINT_ATTRf(sample_regs_intr, p_hex);
         PRINT_ATTRf(aux_watermark, p_unsigned);
+        PRINT_ATTRf(sample_max_stack, p_unsigned);
 
         return ret;
 }
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index c1f10159804c..028412b32d5a 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -44,6 +44,7 @@ enum {
         PERF_EVSEL__CONFIG_TERM_CALLGRAPH,
         PERF_EVSEL__CONFIG_TERM_STACK_USER,
         PERF_EVSEL__CONFIG_TERM_INHERIT,
+        PERF_EVSEL__CONFIG_TERM_MAX_STACK,
         PERF_EVSEL__CONFIG_TERM_MAX,
 };
 
@@ -56,6 +57,7 @@ struct perf_evsel_config_term {
                 bool    time;
                 char    *callgraph;
                 u64     stack_user;
+                int     max_stack;
                 bool    inherit;
         } val;
 };
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index bcbc983d4b12..89d40bb425e1 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -900,6 +900,7 @@ static const char *config_term_names[__PARSE_EVENTS__TERM_TYPE_NR] = {
         [PARSE_EVENTS__TERM_TYPE_STACKSIZE]             = "stack-size",
         [PARSE_EVENTS__TERM_TYPE_NOINHERIT]             = "no-inherit",
         [PARSE_EVENTS__TERM_TYPE_INHERIT]               = "inherit",
+        [PARSE_EVENTS__TERM_TYPE_MAX_STACK]             = "max-stack",
 };
 
 static bool config_term_shrinked;
@@ -995,6 +996,9 @@ do {									   \
         case PARSE_EVENTS__TERM_TYPE_NAME:
                 CHECK_TYPE_VAL(STR);
                 break;
+        case PARSE_EVENTS__TERM_TYPE_MAX_STACK:
+                CHECK_TYPE_VAL(NUM);
+                break;
         default:
                 err->str = strdup("unknown term");
                 err->idx = term->err_term;
@@ -1040,6 +1044,7 @@ static int config_term_tracepoint(struct perf_event_attr *attr,
         case PARSE_EVENTS__TERM_TYPE_STACKSIZE:
         case PARSE_EVENTS__TERM_TYPE_INHERIT:
         case PARSE_EVENTS__TERM_TYPE_NOINHERIT:
+        case PARSE_EVENTS__TERM_TYPE_MAX_STACK:
                 return config_term_common(attr, term, err);
         default:
                 if (err) {
@@ -1109,6 +1114,9 @@ do {								\
                 case PARSE_EVENTS__TERM_TYPE_NOINHERIT:
                         ADD_CONFIG_TERM(INHERIT, inherit, term->val.num ? 0 : 1);
                         break;
+                case PARSE_EVENTS__TERM_TYPE_MAX_STACK:
+                        ADD_CONFIG_TERM(MAX_STACK, max_stack, term->val.num);
+                        break;
                 default:
                         break;
                 }
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index d740c3ca9a1d..46c05ccd5dfe 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -68,6 +68,7 @@ enum {
         PARSE_EVENTS__TERM_TYPE_STACKSIZE,
         PARSE_EVENTS__TERM_TYPE_NOINHERIT,
         PARSE_EVENTS__TERM_TYPE_INHERIT,
+        PARSE_EVENTS__TERM_TYPE_MAX_STACK,
         __PARSE_EVENTS__TERM_TYPE_NR,
 };
 
diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index 1477fbc78993..01af1ee90a27 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -199,6 +199,7 @@ branch_type		{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_BRANCH_SAMPLE_TYPE
 time                    { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_TIME); }
 call-graph              { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_CALLGRAPH); }
 stack-size              { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_STACKSIZE); }
+max-stack               { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_MAX_STACK); }
 inherit                 { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_INHERIT); }
 no-inherit              { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_NOINHERIT); }
 ,                       { return ','; }
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 2335b2824d8a..43d30ea87b7e 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -593,6 +593,7 @@ do { 						\
         if (bswap_safe(f, 0))                   \
                 attr->f = bswap_##sz(attr->f);  \
 } while(0)
+#define bswap_field_16(f) bswap_field(f, 16)
 #define bswap_field_32(f) bswap_field(f, 32)
 #define bswap_field_64(f) bswap_field(f, 64)
 
@@ -608,6 +609,7 @@ do { 						\
         bswap_field_64(sample_regs_user);
         bswap_field_32(sample_stack_user);
         bswap_field_32(aux_watermark);
+        bswap_field_16(sample_max_stack);
 
         /*
          * After read_format are bitfields. Check read_format because