Re: [PATCH 3/3] x86/ftrace: Use text_poke()

[Steven Rostedt]

On Fri, 4 Oct 2019 16:44:35 +0200
Daniel Bristot de Oliveira <bristot@xxxxxxxxxx> wrote:

> On 04/10/2019 15:40, Steven Rostedt wrote:
> > On Fri, 4 Oct 2019 10:10:47 +0200
> > Daniel Bristot de Oliveira <bristot@xxxxxxxxxx> wrote:
> >   
> >> [ In addition ]
> >>
> >> Currently, ftrace_rec entries are ordered inside the group of functions, but
> >> "groups of function" are not ordered. So, the current int3 handler does a (*):
> >>
> >> for_each_group_of_functions:
> >> 	check if the ip is in the range    ----> n by the number of groups.
> >> 		do a bsearch.		   ----> log(n) by the numbers of entry
> >> 					         in the group.
> >>
> >> If, instead, it uses an ordered vector, the complexity would be log(n) by the
> >> total number of entries, which is better. So, how bad is the idea of:  
> > BTW, I'm currently rewriting the grouping of the vectors, in order to
> > shrink the size of each dyn_ftrace_rec (as we discussed at Kernel
> > Recipes). I can make the groups all sorted in doing so, thus we can
> > load the sorted if that's needed, without doing anything special.
> >   
> 
> Good! if you do they sorted and store the amount of entries in a variable, we
> can have things done for a future "optimized" version.
> 

You mean something like this?

-- Steve