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tracing: Use trace_seq instead of open code string appending

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The filter code does open code string appending to produce an error message.
Instead it can be simplified by using trace_seq function helpers.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (VMware) 2018-02-22 23:14:04 -05:00
parent a0ff08fd4e
commit 559d421267
1 changed files with 22 additions and 33 deletions
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55
kernel/trace/trace_events_filter.c
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@ -675,47 +675,36 @@ static int replace_filter_string(struct event_filter *filter,
return 0;
}
static int append_filter_string(struct event_filter *filter,
char *string)
{
int newlen;
char *new_filter_string;
if (WARN_ON(!filter->filter_string))
return -EINVAL;
newlen = strlen(filter->filter_string) + strlen(string) + 1;
new_filter_string = kmalloc(newlen, GFP_KERNEL);
if (!new_filter_string)
return -ENOMEM;
strcpy(new_filter_string, filter->filter_string);
strcat(new_filter_string, string);
kfree(filter->filter_string);
filter->filter_string = new_filter_string;
return 0;
}
static void append_filter_err(struct filter_parse_state *ps,
struct event_filter *filter)
{
struct trace_seq *s;
int pos = ps->lasterr_pos;
char *buf, *pbuf;
char *buf;
int len;
buf = (char *)__get_free_page(GFP_KERNEL);
if (!buf)
if (WARN_ON(!filter->filter_string))
return;
append_filter_string(filter, "\n");
memset(buf, ' ', PAGE_SIZE);
if (pos > PAGE_SIZE - 128)
pos = 0;
buf[pos] = '^';
pbuf = &buf[pos] + 1;
s = kmalloc(sizeof(*s), GFP_KERNEL);
if (!s)
return;
trace_seq_init(s);
sprintf(pbuf, "\nparse_error: %s\n", err_text[ps->lasterr]);
append_filter_string(filter, buf);
free_page((unsigned long) buf);
len = strlen(filter->filter_string);
if (pos > len)
len = pos;
trace_seq_puts(s, filter->filter_string);
trace_seq_printf(s, "\n%*s", pos, "^");
trace_seq_printf(s, "\nparse_error: %s\n", err_text[ps->lasterr]);
trace_seq_putc(s, 0);
buf = kmemdup_nul(s->buffer, s->seq.len, GFP_KERNEL);
if (buf) {
kfree(filter->filter_string);
filter->filter_string = buf;
}
kfree(s);
}
static inline struct event_filter *event_filter(struct trace_event_file *file)