Re: [PATCH v2] arm64: fix unwind_frame() for filtered out fn for function graph tracing

2017-09-12 Thread Pratyush Anand
On Wednesday 13 September 2017 08:12 AM, Will Deacon wrote: On Tue, Sep 12, 2017 at 10:54:28AM +0100, James Morse wrote: Hi Pratyush, On 01/09/17 06:48, Pratyush Anand wrote: do_task_stat() calls get_wchan(), which further does unbind_frame(). unbind_frame() restores frame->pc to original

Re: [PATCH v2] arm64: fix unwind_frame() for filtered out fn for function graph tracing

2017-09-12 Thread Pratyush Anand
On Wednesday 13 September 2017 08:12 AM, Will Deacon wrote: On Tue, Sep 12, 2017 at 10:54:28AM +0100, James Morse wrote: Hi Pratyush, On 01/09/17 06:48, Pratyush Anand wrote: do_task_stat() calls get_wchan(), which further does unbind_frame(). unbind_frame() restores frame->pc to original

Re: [PATCH v2] arm64: fix unwind_frame() for filtered out fn for function graph tracing

2017-09-12 Thread Will Deacon
On Tue, Sep 12, 2017 at 10:54:28AM +0100, James Morse wrote: > Hi Pratyush, > > On 01/09/17 06:48, Pratyush Anand wrote: > > do_task_stat() calls get_wchan(), which further does unbind_frame(). > > unbind_frame() restores frame->pc to original value in case function > > graph tracer has modified

Re: [PATCH v2] arm64: fix unwind_frame() for filtered out fn for function graph tracing

2017-09-12 Thread Will Deacon
On Tue, Sep 12, 2017 at 10:54:28AM +0100, James Morse wrote: > Hi Pratyush, > > On 01/09/17 06:48, Pratyush Anand wrote: > > do_task_stat() calls get_wchan(), which further does unbind_frame(). > > unbind_frame() restores frame->pc to original value in case function > > graph tracer has modified

Re: [PATCH v2] arm64: fix unwind_frame() for filtered out fn for function graph tracing

2017-09-12 Thread James Morse
Hi Pratyush, On 01/09/17 06:48, Pratyush Anand wrote: > do_task_stat() calls get_wchan(), which further does unbind_frame(). > unbind_frame() restores frame->pc to original value in case function > graph tracer has modified a return address (LR) in a stack frame to hook > a function return.

Re: [PATCH v2] arm64: fix unwind_frame() for filtered out fn for function graph tracing

2017-09-12 Thread James Morse
Hi Pratyush, On 01/09/17 06:48, Pratyush Anand wrote: > do_task_stat() calls get_wchan(), which further does unbind_frame(). > unbind_frame() restores frame->pc to original value in case function > graph tracer has modified a return address (LR) in a stack frame to hook > a function return.

[PATCH v2] arm64: fix unwind_frame() for filtered out fn for function graph tracing

2017-08-31 Thread Pratyush Anand
do_task_stat() calls get_wchan(), which further does unbind_frame(). unbind_frame() restores frame->pc to original value in case function graph tracer has modified a return address (LR) in a stack frame to hook a function return. However, if function graph tracer has hit a filtered function, then

[PATCH v2] arm64: fix unwind_frame() for filtered out fn for function graph tracing

2017-08-31 Thread Pratyush Anand
do_task_stat() calls get_wchan(), which further does unbind_frame(). unbind_frame() restores frame->pc to original value in case function graph tracer has modified a return address (LR) in a stack frame to hook a function return. However, if function graph tracer has hit a filtered function, then