[PATCH 03/11] dynamic_debug: Remove uses of KERN_CONT in dynamic_emit_prefix

Jason Baron
2011-08-11T18:36:37Z

From: Joe Perches <joe@perches.com>

Multiple printks with KERN_CONT can be interleaved by
other printks. Reduce the likelihood of that interleaving
by consolidating multiple calls to printk.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
---
lib/dynamic_debug.c | 34 +++++++++++++++++++++++-----------
1 files changed, 23 insertions(+), 11 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 3721709..a3eb6ab 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -430,23 +430,35 @@ static int ddebug_exec_query(char *query_string)

static int dynamic_emit_prefix(const struct _ddebug *descriptor)
{
- int res;
+ char tid[sizeof(int) + sizeof(int)/2 + 4];
+ char lineno[sizeof(int) + sizeof(int)/2];

- res = printk(KERN_DEBUG);
if (descriptor->flags & _DPRINTK_FLAGS_INCL_TID) {
if (in_interrupt())
- res += printk(KERN_CONT "<intr> ");
+ snprintf(tid, sizeof(tid), "%s", "<intr> ");
else
- res += printk(KERN_CONT "[%d] ", task_pid_vnr(current));
+ snprintf(tid, sizeof(tid), "[%d] ",
+ task_pid_vnr(current));
+ } else {
+ tid[0] = 0;
}
- if (descriptor->flags & _DPRINTK_FLAGS_INCL_MODNAME)
- res += printk(KERN_CONT "%s:", descriptor->modname);
- if (descriptor->flags & _DPRINTK_FLAGS_INCL_FUNCNAME)
- res += printk(KERN_CONT "%s:", descriptor->function);
- if (descriptor->flags & _DPRINTK_FLAGS_INCL_LINENO)
- res += printk(KERN_CONT "%d ", descriptor->lineno);

- return res;
+ if (descriptor->flags & _DPRINTK_FLAGS_INCL_LINENO)
+ snprintf(lineno, sizeof(lineno), "%d", descriptor->lineno);
+ else
+ lineno[0] = 0;
+
+ return printk(KERN_DEBUG "%s%s%s%s%s%s",
+ tid,
+ (descriptor->flags & _DPRINTK_FLAGS_INCL_MODNAME) ?
+ descriptor->modname : "",
+ (descriptor->flags & _DPRINTK_FLAGS_INCL_MODNAME) ?
+ ":" : "",
+ (descriptor->flags & _DPRINTK_FLAGS_INCL_FUNCNAME) ?
+ descriptor->function : "",
+ (descriptor->flags & _DPRINTK_FLAGS_INCL_FUNCNAME) ?
+ ":" : "",
+ lineno);
}

int __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...)
--
1.7.5.4