On Tue, 13 Aug 2019 18:31:14 +0100 Will Deacon <w...@kernel.org> wrote:
> Hi Steve, > > On Thu, Aug 08, 2019 at 10:24:40PM -0400, Steven Rostedt wrote: > > On Fri, 9 Aug 2019 10:17:19 +0800 > > Jiping Ma <jiping....@windriver.com> wrote: > > > On 2019年08月09日 01:24, Steven Rostedt wrote: > > > > On Thu, 8 Aug 2019 18:11:53 +0100 > > > > Will Deacon <w...@kernel.org> wrote: > > > > > > > >>> We could make it more descriptive of what it will do and not the > > > >>> reason > > > >>> for why it is done... > > > >>> > > > >>> > > > >>> ARCH_FTRACE_SHIFT_STACK_TRACER > > > >> Acked-by: Will Deacon <w...@kernel.org> > > > > Thanks Will! > > > > > > > > Here's the official patch. > > > > > > > > From: "Steven Rostedt (VMware)" <rost...@goodmis.org> > > > > > > > > Most archs (well at least x86) store the function call return address > > > > on the > > > > stack before storing the local variables for the function. The max stack > > > > tracer depends on this in its algorithm to display the stack size of > > > > each > > > > function it finds in the back trace. > > > > > > > > Some archs (arm64), may store the return address (from its link > > > > register) > > > > just before calling a nested function. There's no reason to save the > > > > link > > > > register on leaf functions, as it wont be updated. This breaks the > > > > algorithm > > > > of the max stack tracer. > > > > > > > > Add a new define ARCH_RET_ADDR_AFTER_LOCAL_VARS that an architecture > > > > may set > > > > > > ARCH_FTRACE_SHIFT_STACK_TRACER is used in the code. > > > > Ah, I did a s/x/y/ to the diff of the patch, but not the change log. > > Thanks for pointing that out. I also need to update the comment in 2/2. > > Are you going to post another version of this or have you queued it already? > Just want to make sure it doesn't slip through the cracks. > Ah, it's in my queue. I should post a new version :-/ Thanks for the reminder. -- Steve
