[PATCH v1 04/12] sys-rq: Add option to soft dump

Mike Waychison
2010-11-03T01:30:18Z

It is very useful to provide some means to force the kernel logs to make it out
via the kmsg_oops implementations on the console. Add a new option 'Y' to
sysrq to allow dumping of logs to kmsg_dumper drivers.

Signed-off-by: Mike Waychison <mikew@google.com>
---
drivers/char/sysrq.c | 14 +++++++++++++-
1 files changed, 13 insertions(+), 1 deletions(-)

diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c
index ef31bb8..888efc5 100644
--- a/drivers/char/sysrq.c
+++ b/drivers/char/sysrq.c
@@ -41,6 +41,7 @@
#include <linux/oom.h>
#include <linux/slab.h>
#include <linux/input.h>
+#include <linux/kmsg_dump.h>

#include <asm/ptrace.h>
#include <asm/irq_regs.h>
@@ -395,6 +396,17 @@ static struct sysrq_key_op sysrq_unrt_op = {
.enable_mask = SYSRQ_ENABLE_RTNICE,
};

+static void sysrq_handle_softdump(int key)
+{
+ kmsg_dump(KMSG_DUMP_SOFT, NULL);
+}
+static struct sysrq_key_op sysrq_softdump_op = {
+ .handler = sysrq_handle_softdump,
+ .help_msg = "soft-dump(Y)",
+ .action_msg = "Trigger a soft dump",
+ .enable_mask = SYSRQ_ENABLE_DUMP,
+};
+
/* Key Operations table and lock */
static DEFINE_SPINLOCK(sysrq_key_table_lock);

@@ -451,7 +463,7 @@ static struct sysrq_key_op *sysrq_key_table[36] = {
/* x: May be registered on ppc/powerpc for xmon */
NULL, /* x */
/* y: May be registered on sparc64 for global register dump */
- NULL, /* y */
+ &sysrq_softdump_op, /* y */
&sysrq_ftrace_dump_op, /* z */
};