* [PATCH] arm64:ftrace: add save_stack_trace_regs()
@ 2015-07-31 9:21 Pratyush Anand
2016-09-01 11:27 ` Pratyush Anand
0 siblings, 1 reply; 4+ messages in thread
From: Pratyush Anand @ 2015-07-31 9:21 UTC (permalink / raw)
To: linux-arm-kernel
Implement save_stack_trace_regs, so that stacktrace of a kprobe events can be
obtained.
Signed-off-by: Pratyush Anand <panand@redhat.com>
---
Function will be useful only after having ARM64 kprobes upstreamed.
However, since there is no dependency in applying the patch, so it may be
upstreamed independently (if there is no other review comment).
I see following stack trace for kfree with this patch in one of the case.
echo stacktrace > /sys/kernel/debug/tracing/trace_options
echo "p kfree" >> /sys/kernel/debug/tracing/kprobe_events
echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable
more /sys/kernel/debug/tracing/trace
bash-3868 [001] d... 2863.068271: p_kfree_0: (kfree+0x0/0x194)
bash-3868 [001] d... 2863.068276: <stack trace>
=> kfree
=> syscall_trace_exit
=> __sys_trace_return_skipped
arch/arm64/kernel/stacktrace.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
index 407991bf79f5..c7fa0431ef3e 100644
--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c
@@ -97,6 +97,24 @@ static int save_trace(struct stackframe *frame, void *d)
return trace->nr_entries >= trace->max_entries;
}
+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 = 0;
+
+ frame.fp = regs->regs[29];
+ frame.sp = regs->sp;
+ frame.pc = regs->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_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
struct stack_trace_data data;
--
2.4.3
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH] arm64:ftrace: add save_stack_trace_regs()
2015-07-31 9:21 [PATCH] arm64:ftrace: add save_stack_trace_regs() Pratyush Anand
@ 2016-09-01 11:27 ` Pratyush Anand
2016-09-01 11:39 ` Will Deacon
0 siblings, 1 reply; 4+ messages in thread
From: Pratyush Anand @ 2016-09-01 11:27 UTC (permalink / raw)
To: linux-arm-kernel
On Fri, Jul 31, 2015 at 2:51 PM, Pratyush Anand <panand@redhat.com> wrote:
> Implement save_stack_trace_regs, so that stacktrace of a kprobe events can be
> obtained.
>
> Signed-off-by: Pratyush Anand <panand@redhat.com>
> ---
> Function will be useful only after having ARM64 kprobes upstreamed.
> However, since there is no dependency in applying the patch, so it may be
> upstreamed independently (if there is no other review comment).
Since kprobe is already in mainline now. So any comment for this patch?
It still applies cleanly to the latest upstream.
~Pratyush
>
> I see following stack trace for kfree with this patch in one of the case.
>
> echo stacktrace > /sys/kernel/debug/tracing/trace_options
> echo "p kfree" >> /sys/kernel/debug/tracing/kprobe_events
> echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable
> more /sys/kernel/debug/tracing/trace
> bash-3868 [001] d... 2863.068271: p_kfree_0: (kfree+0x0/0x194)
> bash-3868 [001] d... 2863.068276: <stack trace>
> => kfree
> => syscall_trace_exit
> => __sys_trace_return_skipped
>
> arch/arm64/kernel/stacktrace.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
> index 407991bf79f5..c7fa0431ef3e 100644
> --- a/arch/arm64/kernel/stacktrace.c
> +++ b/arch/arm64/kernel/stacktrace.c
> @@ -97,6 +97,24 @@ static int save_trace(struct stackframe *frame, void *d)
> return trace->nr_entries >= trace->max_entries;
> }
>
> +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 = 0;
> +
> + frame.fp = regs->regs[29];
> + frame.sp = regs->sp;
> + frame.pc = regs->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_tsk(struct task_struct *tsk, struct stack_trace *trace)
> {
> struct stack_trace_data data;
> --
> 2.4.3
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 4+ messages in thread* [PATCH] arm64:ftrace: add save_stack_trace_regs()
2016-09-01 11:27 ` Pratyush Anand
@ 2016-09-01 11:39 ` Will Deacon
2016-09-01 12:09 ` Pratyush Anand
0 siblings, 1 reply; 4+ messages in thread
From: Will Deacon @ 2016-09-01 11:39 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Sep 01, 2016 at 04:57:30PM +0530, Pratyush Anand wrote:
> On Fri, Jul 31, 2015 at 2:51 PM, Pratyush Anand <panand@redhat.com> wrote:
> > Implement save_stack_trace_regs, so that stacktrace of a kprobe events can be
> > obtained.
> >
> > Signed-off-by: Pratyush Anand <panand@redhat.com>
> > ---
> > Function will be useful only after having ARM64 kprobes upstreamed.
> > However, since there is no dependency in applying the patch, so it may be
> > upstreamed independently (if there is no other review comment).
>
>
> Since kprobe is already in mainline now. So any comment for this patch?
> It still applies cleanly to the latest upstream.
It would be nice if David or Akashi could review/test it.
Will
> > I see following stack trace for kfree with this patch in one of the case.
> >
> > echo stacktrace > /sys/kernel/debug/tracing/trace_options
> > echo "p kfree" >> /sys/kernel/debug/tracing/kprobe_events
> > echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable
> > more /sys/kernel/debug/tracing/trace
> > bash-3868 [001] d... 2863.068271: p_kfree_0: (kfree+0x0/0x194)
> > bash-3868 [001] d... 2863.068276: <stack trace>
> > => kfree
> > => syscall_trace_exit
> > => __sys_trace_return_skipped
> >
> > arch/arm64/kernel/stacktrace.c | 18 ++++++++++++++++++
> > 1 file changed, 18 insertions(+)
> >
> > diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
> > index 407991bf79f5..c7fa0431ef3e 100644
> > --- a/arch/arm64/kernel/stacktrace.c
> > +++ b/arch/arm64/kernel/stacktrace.c
> > @@ -97,6 +97,24 @@ static int save_trace(struct stackframe *frame, void *d)
> > return trace->nr_entries >= trace->max_entries;
> > }
> >
> > +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 = 0;
> > +
> > + frame.fp = regs->regs[29];
> > + frame.sp = regs->sp;
> > + frame.pc = regs->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_tsk(struct task_struct *tsk, struct stack_trace *trace)
> > {
> > struct stack_trace_data data;
> > --
> > 2.4.3
> >
> >
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel at lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
^ permalink raw reply [flat|nested] 4+ messages in thread* [PATCH] arm64:ftrace: add save_stack_trace_regs()
2016-09-01 11:39 ` Will Deacon
@ 2016-09-01 12:09 ` Pratyush Anand
0 siblings, 0 replies; 4+ messages in thread
From: Pratyush Anand @ 2016-09-01 12:09 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Sep 1, 2016 at 5:09 PM, Will Deacon <will.deacon@arm.com> wrote:
> On Thu, Sep 01, 2016 at 04:57:30PM +0530, Pratyush Anand wrote:
>> On Fri, Jul 31, 2015 at 2:51 PM, Pratyush Anand <panand@redhat.com> wrote:
>> > Implement save_stack_trace_regs, so that stacktrace of a kprobe events can be
>> > obtained.
>> >
>> > Signed-off-by: Pratyush Anand <panand@redhat.com>
>> > ---
>> > Function will be useful only after having ARM64 kprobes upstreamed.
>> > However, since there is no dependency in applying the patch, so it may be
>> > upstreamed independently (if there is no other review comment).
>>
>>
>> Since kprobe is already in mainline now. So any comment for this patch?
>> It still applies cleanly to the latest upstream.
Humm..it just applies cleanly, but does not even compile with latest
kernel. I will rebase, retest and will resend then.
~Pratyush
>
> It would be nice if David or Akashi could review/test it.
>
> Will
>
>> > I see following stack trace for kfree with this patch in one of the case.
>> >
>> > echo stacktrace > /sys/kernel/debug/tracing/trace_options
>> > echo "p kfree" >> /sys/kernel/debug/tracing/kprobe_events
>> > echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable
>> > more /sys/kernel/debug/tracing/trace
>> > bash-3868 [001] d... 2863.068271: p_kfree_0: (kfree+0x0/0x194)
>> > bash-3868 [001] d... 2863.068276: <stack trace>
>> > => kfree
>> > => syscall_trace_exit
>> > => __sys_trace_return_skipped
>> >
>> > arch/arm64/kernel/stacktrace.c | 18 ++++++++++++++++++
>> > 1 file changed, 18 insertions(+)
>> >
>> > diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
>> > index 407991bf79f5..c7fa0431ef3e 100644
>> > --- a/arch/arm64/kernel/stacktrace.c
>> > +++ b/arch/arm64/kernel/stacktrace.c
>> > @@ -97,6 +97,24 @@ static int save_trace(struct stackframe *frame, void *d)
>> > return trace->nr_entries >= trace->max_entries;
>> > }
>> >
>> > +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 = 0;
>> > +
>> > + frame.fp = regs->regs[29];
>> > + frame.sp = regs->sp;
>> > + frame.pc = regs->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_tsk(struct task_struct *tsk, struct stack_trace *trace)
>> > {
>> > struct stack_trace_data data;
>> > --
>> > 2.4.3
>> >
>> >
>> > _______________________________________________
>> > linux-arm-kernel mailing list
>> > linux-arm-kernel at lists.infradead.org
>> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>>
^ permalink raw reply [flat|nested] 4+ messages in thread
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2015-07-31 9:21 [PATCH] arm64:ftrace: add save_stack_trace_regs() Pratyush Anand
2016-09-01 11:27 ` Pratyush Anand
2016-09-01 11:39 ` Will Deacon
2016-09-01 12:09 ` Pratyush Anand
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