Hi, Arnaldo On Fri, 7 Sep 2012 17:48:54 -0700, Arnaldo Carvalho de Melo wrote: > Em Mon, Sep 03, 2012 at 11:53:05AM +0900, Namhyung Kim escreveu: >> This is a cleanup and refactoring patchset for the hist printing code >> by adding perf_hpp__format functions and perf_hpp. I believe it makes >> the code easy to maintain and to add new features like upcoming group >> viewing and callchain accumulation. > > I applied this patch series to then get some patches from Jiri's 'perf > diff' series, so that he can use what you did here, as you noticed the > overlap when reviewing his series. > > But then 'perf diff' segfaults :-\ > > I left your patch series + with that overhead column fixlet at my tree, > branch tmp.perf/hpp. > > The segfaults happens here: > > Program received signal SIGSEGV, Segmentation fault. > 0x0000000000498837 in hpp__entry_delta (hpp=0x7fffffffdeb0, he=0xcd6310) at > ui/hist.c:200 > 200 old_percent = 100.0 * he->pair->period / old_total; > Missing separate debuginfos, use: debuginfo-install atk-1.28.0-2.el6.x86_64 > bzip2-libs-1.0.5-7.el6_0.x86_64 elfutils-libelf-0.152-1.el6.x86_64 > elfutils-libs-0.152-1.el6.x86_64 expat-2.0.1-11.el6_2.x86_64 > fontconfig-2.8.0-3.el6.x86_64 freetype-2.3.11-6.el6_2.9.x86_64 > glib2-2.22.5-7.el6.x86_64 gtk2-2.18.9-10.el6.x86_64 libX11-1.3-2.el6.x86_64 > libXau-1.0.5-1.el6.x86_64 libXcomposite-0.4.1-2.el6.x86_64 > libXcursor-1.1.10-2.el6.x86_64 libXdamage-1.1.2-1.el6.x86_64 > libXext-1.1-3.el6.x86_64 libXfixes-4.0.4-1.el6.x86_64 libXi-1.3-3.el6.x86_64 > libXinerama-1.1-1.el6.x86_64 libXrandr-1.3.0-4.el6.x86_64 > libXrender-0.9.5-1.el6.x86_64 libpng-1.2.49-1.el6_2.x86_64 > libselinux-2.0.94-5.3.el6.x86_64 libxcb-1.5-1.el6.x86_64 > nss-softokn-freebl-3.12.9-11.el6.x86_64 pango-1.28.1-3.el6_0.5.x86_64 > perl-libs-5.10.1 > -127.el6.x86_64 pixman-0.18.4-1.el6_0.1.x86_64 > xz-libs-4.999.9-0.3.beta.20091007git.el6.x86_64 zlib-1.2.3-27.el6.x86_64 > (gdb) p he->pair > $1 = (struct hist_entry *) 0x0 > > Please try with: > > perf record -a usleep 1 > perf record -a usleep 1 > perf diff > > it will use perf.data.old and perf.data and will segfault in that branch.
I see the problem. I overlooked he->pair can be NULL when perf diff is running. So the fix will be adding a NULL check before the line. In case of NULL, it will default to 0, so no problem. Thanks, Namhyung diff --git a/tools/perf/ui/hist.c b/tools/perf/ui/hist.c index 16dc486d02be..3c2701fa6be1 100644 --- a/tools/perf/ui/hist.c +++ b/tools/perf/ui/hist.c @@ -196,7 +196,7 @@ static int hpp__entry_delta(struct perf_hpp *hpp, struct hist_entry *he) char buf[32] = " "; old_total = pair_hists->stats.total_period; - if (old_total > 0) + if (old_total > 0 && he->pair) old_percent = 100.0 * he->pair->period / old_total; new_total = hpp->total_period; -- 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/