diff options
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace.c | 3 | ||||
| -rw-r--r-- | kernel/trace/trace_events_hist.c | 34 |
2 files changed, 29 insertions, 8 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 55aec4616d8b..948f321b9df1 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -5678,6 +5678,7 @@ static const char readme_msg[] = "\t [:size=#entries]\n" "\t [:pause][:continue][:clear]\n" "\t [:name=histname1]\n" + "\t [:nohitcount]\n" "\t [:<handler>.<action>]\n" "\t [if <filter>]\n\n" "\t Note, special fields can be used as well:\n" @@ -5734,6 +5735,8 @@ static const char readme_msg[] = "\t The 'clear' parameter will clear the contents of a running\n" "\t hist trigger and leave its current paused/active state\n" "\t unchanged.\n\n" + "\t The 'nohitcount' (or NOHC) parameter will suppress display of\n" + "\t raw hitcount in the histogram.\n\n" "\t The enable_hist and disable_hist triggers can be used to\n" "\t have one event conditionally start and stop another event's\n" "\t already-attached hist trigger. The syntax is analogous to\n" diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 946b2b8f0f2c..a0cd118af527 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -69,7 +69,8 @@ C(INVALID_STR_OPERAND, "String type can not be an operand in expression"), \ C(EXPECT_NUMBER, "Expecting numeric literal"), \ C(UNARY_MINUS_SUBEXPR, "Unary minus not supported in sub-expressions"), \ - C(DIVISION_BY_ZERO, "Division by zero"), + C(DIVISION_BY_ZERO, "Division by zero"), \ + C(NEED_NOHC_VAL, "Non-hitcount value is required for 'nohitcount'"), #undef C #define C(a, b) HIST_ERR_##a @@ -526,6 +527,7 @@ struct hist_trigger_attrs { bool cont; bool clear; bool ts_in_usecs; + bool no_hitcount; unsigned int map_bits; char *assignment_str[TRACING_MAP_VARS_MAX]; @@ -1550,7 +1552,10 @@ parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) ret = parse_assignment(tr, str, attrs); if (ret) goto free; - } else if (strcmp(str, "pause") == 0) + } else if (strcmp(str, "nohitcount") == 0 || + strcmp(str, "NOHC") == 0) + attrs->no_hitcount = true; + else if (strcmp(str, "pause") == 0) attrs->pause = true; else if ((strcmp(str, "cont") == 0) || (strcmp(str, "continue") == 0)) @@ -4377,6 +4382,12 @@ static int create_val_fields(struct hist_trigger_data *hist_data, if (fields_str && (strcmp(fields_str, "hitcount") != 0)) ret = -EINVAL; out: + /* There is only raw hitcount but nohitcount suppresses it. */ + if (j == 1 && hist_data->attrs->no_hitcount) { + hist_err(hist_data->event_file->tr, HIST_ERR_NEED_NOHC_VAL, 0); + ret = -ENOENT; + } + return ret; } @@ -5388,13 +5399,13 @@ static void hist_trigger_entry_print(struct seq_file *m, hist_trigger_print_key(m, hist_data, key, elt); - /* At first, show the raw hitcount always */ - hist_trigger_print_val(m, i, "hitcount", 0, stats, elt); + /* At first, show the raw hitcount if !nohitcount */ + if (!hist_data->attrs->no_hitcount) + hist_trigger_print_val(m, i, "hitcount", 0, stats, elt); for (i = 1; i < hist_data->n_vals; i++) { field_name = hist_field_name(hist_data->fields[i], 0); flags = hist_data->fields[i]->flags; - if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR) continue; @@ -5839,6 +5850,7 @@ static int event_hist_trigger_print(struct seq_file *m, struct hist_trigger_data *hist_data = data->private_data; struct hist_field *field; bool have_var = false; + bool show_val = false; unsigned int i; seq_puts(m, HIST_PREFIX); @@ -5869,12 +5881,16 @@ static int event_hist_trigger_print(struct seq_file *m, continue; } - if (i == HITCOUNT_IDX) + if (i == HITCOUNT_IDX) { + if (hist_data->attrs->no_hitcount) + continue; seq_puts(m, "hitcount"); - else { - seq_puts(m, ","); + } else { + if (show_val) + seq_puts(m, ","); hist_field_print(m, field); } + show_val = true; } if (have_var) { @@ -5925,6 +5941,8 @@ static int event_hist_trigger_print(struct seq_file *m, seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); if (hist_data->enable_timestamps) seq_printf(m, ":clock=%s", hist_data->attrs->clock); + if (hist_data->attrs->no_hitcount) + seq_puts(m, ":nohitcount"); print_actions_spec(m, hist_data); |