tracing: provide trace_seq_reserve()

trace_seq_reserve() allows a caller to reserve space in a trace_seq and
write directly into it. This makes it easier to export binary data to
userspace via the tracing interface, by simply filling in a struct.

Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1 insertions, 0 deletions

diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
index 35c422f..0ae20b8 100644
--- a/kernel/trace/trace_output.h
+++ b/kernel/trace/trace_output.h
@@ -33,6 +33,7 @@ int trace_seq_puts(struct trace_seq *s, const char *str);
 int trace_seq_putc(struct trace_seq *s, unsigned char c);
 int trace_seq_putmem(struct trace_seq *s, void *mem, size_t len);
 int trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len);
+void *trace_seq_reserve(struct trace_seq *s, size_t len);
 int trace_seq_path(struct trace_seq *s, struct path *path);
 int seq_print_userip_objs(const struct userstack_entry *entry,
 			  struct trace_seq *s, unsigned long sym_flags);