perf session: Create kernel maps in the constructor
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From: Arnaldo Carvalho de Melo on 28 Jan 2010 19:50 Em Thu, Jan 28, 2010 at 03:59:38PM -0500, Masami Hiramatsu escreveu: > Arnaldo Carvalho de Melo wrote: > > Em Thu, Jan 28, 2010 at 11:28:29AM -0500, Masami Hiramatsu escreveu: > >> Yeah, and if you can separate an interface only for handling symbols > >> from debug/elf binaries, it will be helpful for me too. > > It was done on this same series, now you can do as the patch at the end > > of this message, that will be on my next series, does. > Great! thank you! <SNIP> > > you'll get ipv6.ko located and loaded, mod->dso->long_name thus will > > have the file to use with libdwarf and sym->start will have the > > unrelocated address, and mod->start will have where ipv6 is loaded in > > kernel space > Oh, nice :-) Is that available for the modules which aren't loaded? No it isn't, what usecase do you see where you would like to look at non loaded modules? Traversing the /lib/modules passed can be made to just create DSOs, not maps if we need it. Maps when created using one of these DSOs would find them on the list. > And yeah, I'd like to support modules and it will requires some > enhancement in kprobe-tracer too. Ok <SNIP> > > With the recent modifications done to untie the session and symbol > > layers, 'perf probe' now can use just the symbols layer. > Could you remove session.kmap too? > other parts look good to me. I'll haven't done that just to keep the patch as small as possible :-) But will do before submitting. > Thank you, You're welcome, - Arnaldo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Masami Hiramatsu on 29 Jan 2010 02:00
Arnaldo Carvalho de Melo wrote: > Em Thu, Jan 28, 2010 at 03:59:38PM -0500, Masami Hiramatsu escreveu: >>> you'll get ipv6.ko located and loaded, mod->dso->long_name thus will >>> have the file to use with libdwarf and sym->start will have the >>> unrelocated address, and mod->start will have where ipv6 is loaded in >>> kernel space > >> Oh, nice :-) Is that available for the modules which aren't loaded? > > No it isn't, what usecase do you see where you would like to look at non > loaded modules? Traversing the /lib/modules passed can be made to just > create DSOs, not maps if we need it. Maps when created using one of these > DSOs would find them on the list. One usecase I thought is probing module init code for checking/debugging driver initialization routine. For this purpose, build-id checking also should be solved. If the module is not loaded, we can't check build-id in that time. I think we can compare it when loading the module, in kernel, if we can pass target build-id to kprobe-tracer. >> And yeah, I'd like to support modules and it will requires some >> enhancement in kprobe-tracer too. > > Ok > > <SNIP> >>> With the recent modifications done to untie the session and symbol >>> layers, 'perf probe' now can use just the symbols layer. > >> Could you remove session.kmap too? >> other parts look good to me. > > I'll haven't done that just to keep the patch as small as possible :-) > But will do before submitting. Thanks! :-) -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America), Inc. Software Solutions Division e-mail: mhiramat(a)redhat.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |