-- Masami HIRAMATSU Linux Technology Research Center, System Productivity Research Dept. Center for Technology Innovation - Systems Engineering Hitachi, Ltd., Research & Development Group E-mail: masami.hiramatsu...@hitachi.com
>-----Original Message----- >From: Arnaldo Carvalho de Melo [mailto:a...@kernel.org] >Sent: Thursday, September 24, 2015 10:50 AM >To: Wangnan (F) >Cc: linux-kernel@vger.kernel.org; lize...@huawei.com; pi3or...@163.com; >Namhyung Kim; Jiri Olsa; 平松雅巳 / HIRAMATU,MASAMI >Subject: Re: [PATCH] perf probe: Fix module probing with shortname > >Em Wed, Sep 23, 2015 at 01:03:19PM -0300, Arnaldo Carvalho de Melo escreveu: >> Em Tue, Sep 22, 2015 at 11:49:02PM -0300, Arnaldo Carvalho de Melo escreveu: >> > Em Wed, Sep 23, 2015 at 09:14:44AM +0800, Wangnan (F) escreveu: >> > > On 2015/9/22 21:35, Arnaldo Carvalho de Melo wrote: >> > > >Em Tue, Sep 22, 2015 at 03:34:32AM +0000, Wang Nan escreveu: >> > > >>This is caused by a misunderstood of dso->kernel in >> > > >>kernel_get_module_dso() >> > > >>that, for kernel module, dso->kernel is DSO_TYPE_USER. dso->kernel is >> > > >>DSO_TYPE_KERNEL >> > > >>iff dso is vmlinux. >> > > >Kernel modules having DSO_TYPE_USER seems to be the bug, no? I'll try to >> > > >check that... > >> > > I also noticed this problem when I working on commit >> > > 1f121b03d058dd07199d8924373d3c52a207f63b ("perf tools: Deal with >> > > kernel module names in '[]' correctly") ;) > >> > Thanks for working on this, it is an area that needs cleaning up, too >> > many ways to say what a dso is, will study your findings and try to come >> > up with a patch proposal tomorrow. >> > > So care must be taken. >> >> So, yes, there are multiple uses for this dso->kernel thing, we need to >> look at each one and go on clarifying it so that this gets corrected and >> sane, but I think we need some helpers to clarify all this, namely: >> >> Adding DSO_TYPE_KMODULE and DSO_TYPE_GUEST_KMODULE, setting >> dso->kernel with it when loading host and guest kernel modules and >> adding: >> >> bool dso__is_host_kernel(struct dso *dso) >> bool dso__is_host_kmodule(struct dso *dso) >> >> bool dso__is_guest_kernel(struct dso *dso) > >So I tried this, ended up basically using __map__is_kernel(), in several >places, which I think is right, and I've stashed in my tmp.perf/core >branch so that you can take a look. > >But then I realized that we already have a better way to achieve what is >needed in that function, see the patch below, fixed things for me: Hmm, this is a bit hacky, but yes, it looks good to me. However, I hope to have above solution, for future use. Acked-by: Masami Hiramatsu <masami.hiramatsu...@hitachi.com> Thanks! > >diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c >index 2b78e8f19b45..7fb0533ab18c 100644 >--- a/tools/perf/util/probe-event.c >+++ b/tools/perf/util/probe-event.c >@@ -269,12 +269,13 @@ static int kernel_get_module_dso(const char *module, >struct dso **pdso) > int ret = 0; > > if (module) { >- list_for_each_entry(dso, &host_machine->dsos.head, node) { >- if (!dso->kernel) >- continue; >- if (strncmp(dso->short_name + 1, module, >- dso->short_name_len - 2) == 0) >- goto found; >+ char module_name[128]; >+ >+ snprintf(module_name, sizeof(module_name), "[%s]", module); >+ map = map_groups__find_by_name(&host_machine->kmaps, >MAP__FUNCTION, module_name); >+ if (map) { >+ dso = map->dso; >+ goto found; > } > pr_debug("Failed to find module %s.\n", module); > return -ENOENT; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/