[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <6698c7b983cc20ec84becc757362f48a8948762d.1237813499.git.eduard.munteanu@linux360.ro>
Date: Mon, 23 Mar 2009 15:12:22 +0200
From: Eduard - Gabriel Munteanu <eduard.munteanu@...ux360.ro>
To: mingo@...e.hu
Cc: rostedt@...dmis.org, compudj@...stal.dyndns.org,
fweisbec@...il.com, penberg@...helsinki.fi,
paulmck@...ux.vnet.ibm.com,
Eduard - Gabriel Munteanu <eduard.munteanu@...ux360.ro>,
linux-kernel@...r.kernel.org
Subject: [PATCH 2/7] 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@...ux360.ro>
---
kernel/trace/trace_output.c | 13 +++++++++++++
kernel/trace/trace_output.h | 1 +
2 files changed, 14 insertions(+), 0 deletions(-)
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 9fc8150..bdcc3fe 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -116,6 +116,19 @@ int trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len)
return trace_seq_putmem(s, hex, j);
}
+void *trace_seq_reserve(struct trace_seq *s, size_t len)
+{
+ void *ret;
+
+ if (len > ((PAGE_SIZE - 1) - s->len))
+ return NULL;
+
+ ret = s->buffer + s->len;
+ s->len += len;
+
+ return ret;
+}
+
int trace_seq_path(struct trace_seq *s, struct path *path)
{
unsigned char *p;
diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
index 551a25a..cbc0ec8 100644
--- a/kernel/trace/trace_output.h
+++ b/kernel/trace/trace_output.h
@@ -27,6 +27,7 @@ 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);
--
1.6.0.6
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists