diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 4e342d354c12..988a35263fdd 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3872,6 +3872,7 @@ static const char readme_msg[] = "\t .sym-offset display an address as a symbol and offset\n" "\t .execname display a common_pid as a program name\n" "\t .syscall display a syscall id as a syscall name\n\n" + "\t .log2 display log2 value rather than raw number\n\n" "\t The 'pause' parameter can be used to pause an existing hist\n" "\t trigger or to start a hist trigger but not log any events\n" "\t until told to do so. 'continue' can be used to start or\n" diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index bdea5603cbde..23df38aab503 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -68,6 +68,13 @@ static u64 hist_field_pstring(struct hist_field *hist_field, void *event) return (u64)(unsigned long)*addr; } +static u64 hist_field_log2(struct hist_field *hist_field, void *event) +{ + u64 val = *(u64 *)(event + hist_field->field->offset); + + return (u64) ilog2(roundup_pow_of_two(val)); +} + #define DEFINE_HIST_FIELD_FN(type) \ static u64 hist_field_##type(struct hist_field *hist_field, void *event)\ { \ @@ -111,6 +118,7 @@ enum hist_field_flags { HIST_FIELD_FL_EXECNAME = 64, HIST_FIELD_FL_SYSCALL = 128, HIST_FIELD_FL_STACKTRACE = 256, + HIST_FIELD_FL_LOG2 = 512, }; struct hist_trigger_attrs { @@ -358,6 +366,11 @@ static struct hist_field *create_hist_field(struct ftrace_event_field *field, goto out; } + if (flags & HIST_FIELD_FL_LOG2) { + hist_field->fn = hist_field_log2; + goto out; + } + if (is_string_field(field)) { flags |= HIST_FIELD_FL_STRING; @@ -522,6 +535,8 @@ static int create_key_field(struct hist_trigger_data *hist_data, flags |= HIST_FIELD_FL_EXECNAME; else if (strcmp(field_str, "syscall") == 0) flags |= HIST_FIELD_FL_SYSCALL; + else if (strcmp(field_str, "log2") == 0) + flags |= HIST_FIELD_FL_LOG2; else { ret = -EINVAL; goto out; @@ -980,6 +995,9 @@ hist_trigger_entry_print(struct seq_file *m, key + key_field->offset, HIST_STACKTRACE_DEPTH); multiline = true; + } else if (key_field->flags & HIST_FIELD_FL_LOG2) { + seq_printf(m, "%s: ~ 2^%-2llu", key_field->field->name, + *(u64 *)(key + key_field->offset)); } else if (key_field->flags & HIST_FIELD_FL_STRING) { seq_printf(m, "%s: %-50s", key_field->field->name, (char *)(key + key_field->offset)); @@ -1112,6 +1130,8 @@ static const char *get_hist_field_flags(struct hist_field *hist_field) flags_str = "execname"; else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) flags_str = "syscall"; + else if (hist_field->flags & HIST_FIELD_FL_LOG2) + flags_str = "log2"; return flags_str; }