[<prev] [next>] [day] [month] [year] [list]
Message-ID: <CAP+bzvVjW-AbFrHmQ0mqQZ9bn8yfrR4D3FGzovtbEcspGRsVxg@mail.gmail.com>
Date: Tue, 5 Nov 2013 00:00:10 +0800
From: ivan lam <ivan.lam2014@...il.com>
To: linux@....linux.org.uk
Cc: linux-kernel@...r.kernel.org
Subject: [PATCH] arm: add save_stack_trace_regs() support
From: ivan lam <ivan.lam2014@...il.com>
Date: Mon, 4 Nov 2013 23:35:55 +0800
Subject: [PATCH] arm: add save_stack_trace_regs() support
When configure kprobe events of ftrace with stacktrace option enabled
in arm, not stacktrace was recorded after the kprobe was triggered.
Implement the save_stack_trace_regs() function in arm.
After this fix, stacktrace can be recorded, for example:
# mount -t debugfs nodev /sys/kernel/debug
# echo "p:netrx net_rx_action" >> /sys/kernel/debug/tracing/kprobe_events
# echo 1 > /sys/kernel/debug/tracing/events/kprobes/netrx/enable
# echo 1 > /sys/kernel/debug/tracing/options/stacktrace
# echo 1 > /sys/kernel/debug/tracing/tracing_on
# ping 127.0.0.1 -c 1
# echo 0 > /sys/kernel/debug/tracing/tracing_on
# cat /sys/kernel/debug/tracing/trace
# tracer: nop
#
# entries-in-buffer/entries-written: 12/12 #P:1
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
ping-1200 [000] dNs1 667.603250: netrx: (net_rx_action+0x0/0x1f8)
ping-1200 [000] dNs1 667.604738: <stack trace>
=> net_rx_action
=> do_softirq
=> local_bh_enable
=> ip_finish_output
=> ip_output
=> ip_local_out
=> ip_send_skb
=> ip_push_pending_frames
=> raw_sendmsg
=> inet_sendmsg
=> sock_sendmsg
=> SyS_sendto
=> ret_fast_syscall
Signed-off-by: ivan lam <ivan.lam2014@...il.com>
---
arch/arm/kernel/stacktrace.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/arch/arm/kernel/stacktrace.c b/arch/arm/kernel/stacktrace.c
index 00f79e5..2b52fac0 100644
--- a/arch/arm/kernel/stacktrace.c
+++ b/arch/arm/kernel/stacktrace.c
@@ -123,6 +123,25 @@ void save_stack_trace_tsk(struct task_struct
*tsk, struct stack_trace *trace)
trace->entries[trace->nr_entries++] = ULONG_MAX;
}
+void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
+{
+ struct stack_trace_data data;
+ struct stackframe frame;
+
+ data.trace = trace;
+ data.skip = trace->skip;
+ data.no_sched_functions = 1;
+
+ frame.fp = regs->ARM_fp;
+ frame.sp = regs->ARM_sp;
+ frame.lr = regs->ARM_lr;
+ frame.pc = regs->ARM_pc;
+
+ walk_stackframe(&frame, save_trace, &data);
+ if (trace->nr_entries < trace->max_entries)
+ trace->entries[trace->nr_entries++] = ULONG_MAX;
+}
+
void save_stack_trace(struct stack_trace *trace)
{
save_stack_trace_tsk(current, trace);
--
1.7.9.5
--
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