tracing: Generalize per-element hist trigger data

Up until now, hist triggers only needed per-element support for saving
'comm' data, which was saved directly as a private data pointer.

In anticipation of the need to save other data besides 'comm', add a
new hist_elt_data struct for the purpose, and switch the current
'comm'-related code over to that.

Link: http://lkml.kernel.org/r/4502c338c965ddf5fc19fb1ec4764391e001ed4b.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Tom Zanussi 2018-01-15 20:51:53 -06:00 committed by Steven Rostedt (VMware)
parent 100719dcef
commit af6a29bcaf
1 changed files with 43 additions and 33 deletions

View File

@ -289,6 +289,10 @@ static struct hist_field *find_var(struct hist_trigger_data *hist_data,
return NULL;
}
struct hist_elt_data {
char *comm;
};
static const char *hist_field_name(struct hist_field *field,
unsigned int level)
{
@ -503,45 +507,61 @@ static inline void save_comm(char *comm, struct task_struct *task)
memcpy(comm, task->comm, TASK_COMM_LEN);
}
static void hist_trigger_elt_comm_free(struct tracing_map_elt *elt)
static void hist_elt_data_free(struct hist_elt_data *elt_data)
{
kfree((char *)elt->private_data);
kfree(elt_data->comm);
kfree(elt_data);
}
static int hist_trigger_elt_comm_alloc(struct tracing_map_elt *elt)
static void hist_trigger_elt_data_free(struct tracing_map_elt *elt)
{
struct hist_elt_data *elt_data = elt->private_data;
hist_elt_data_free(elt_data);
}
static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
{
struct hist_trigger_data *hist_data = elt->map->private_data;
unsigned int size = TASK_COMM_LEN;
struct hist_elt_data *elt_data;
struct hist_field *key_field;
unsigned int i;
elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
if (!elt_data)
return -ENOMEM;
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
unsigned int size = TASK_COMM_LEN + 1;
elt->private_data = kzalloc(size, GFP_KERNEL);
if (!elt->private_data)
elt_data->comm = kzalloc(size, GFP_KERNEL);
if (!elt_data->comm) {
kfree(elt_data);
return -ENOMEM;
}
break;
}
}
elt->private_data = elt_data;
return 0;
}
static void hist_trigger_elt_comm_init(struct tracing_map_elt *elt)
static void hist_trigger_elt_data_init(struct tracing_map_elt *elt)
{
char *comm = elt->private_data;
struct hist_elt_data *elt_data = elt->private_data;
if (comm)
save_comm(comm, current);
if (elt_data->comm)
save_comm(elt_data->comm, current);
}
static const struct tracing_map_ops hist_trigger_elt_comm_ops = {
.elt_alloc = hist_trigger_elt_comm_alloc,
.elt_free = hist_trigger_elt_comm_free,
.elt_init = hist_trigger_elt_comm_init,
static const struct tracing_map_ops hist_trigger_elt_data_ops = {
.elt_alloc = hist_trigger_elt_data_alloc,
.elt_free = hist_trigger_elt_data_free,
.elt_init = hist_trigger_elt_data_init,
};
static const char *get_hist_field_flags(struct hist_field *hist_field)
@ -1484,21 +1504,6 @@ static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
return 0;
}
static bool need_tracing_map_ops(struct hist_trigger_data *hist_data)
{
struct hist_field *key_field;
unsigned int i;
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
if (key_field->flags & HIST_FIELD_FL_EXECNAME)
return true;
}
return false;
}
static struct hist_trigger_data *
create_hist_data(unsigned int map_bits,
struct hist_trigger_attrs *attrs,
@ -1524,8 +1529,7 @@ create_hist_data(unsigned int map_bits,
if (ret)
goto free;
if (need_tracing_map_ops(hist_data))
map_ops = &hist_trigger_elt_comm_ops;
map_ops = &hist_trigger_elt_data_ops;
hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
map_ops, hist_data);
@ -1713,7 +1717,13 @@ hist_trigger_entry_print(struct seq_file *m,
seq_printf(m, "%s: [%llx] %-55s", field_name,
uval, str);
} else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
char *comm = elt->private_data;
struct hist_elt_data *elt_data = elt->private_data;
char *comm;
if (WARN_ON_ONCE(!elt_data))
return;
comm = elt_data->comm;
uval = *(u64 *)(key + key_field->offset);
seq_printf(m, "%s: %-16s[%10llu]", field_name,