linux/linux-stable.git - Linux kernel stable tree

Age	Commit message (Collapse)	Author
2019-03-11	perf ui browser: Fix ui popup argv browser for many entries	Andi Kleen
	Fix the argv ui browser code to correctly display more entries than fit on the screen without crashing. The problem was some type confusion with pointer types in the ->seek function. Do the argv arithmetic correctly with char ** pointers. Also add some asserts to find overruns and limit the display function correctly. Then finally remove a workaround for this in the res sample browser. Committer testing: 1) Resize the x terminal to have just some 5 lines 2) Use 'perf report --samples 1' to activate the sample browser options in the menu 3) Press ENTER, this will cause the crash: # perf report --samples 1 perf: Segmentation fault -------- backtrace -------- perf[0x5a514a] /lib64/libc.so.6(+0x385bf)[0x7f27281b55bf] /lib64/libc.so.6(+0x161a67)[0x7f27282dea67] /lib64/libslang.so.2(SLsmg_write_wrapped_string+0x82)[0x7f272874a0b2] perf(ui_browser__argv_refresh+0x77)[0x5939a7] perf[0x5924cc] perf(ui_browser__run+0x39)[0x593449] perf(ui__popup_menu+0x83)[0x5a5263] perf[0x59f421] perf(perf_evlist__tui_browse_hists+0x3a0)[0x5a3780] perf(cmd_report+0x2746)[0x447136] perf[0x4a95fe] perf(main+0x61c)[0x42dc6c] /lib64/libc.so.6(__libc_start_main+0xf2)[0x7f27281a1412] perf(_start+0x2d)[0x42de9d] # After applying this patch no crash takes place in such situation. Signed-off-by: Andi Kleen <ak@linux.intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: http://lkml.kernel.org/r/20190311144502.15423-12-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-03-11	perf report: Implement browsing of individual samples	Andi Kleen
	Now 'perf report' can show whole time periods with 'perf script', but the user still has to find individual samples of interest manually. It would be expensive and complicated to search for the right samples in the whole perf file. Typically users only need to look at a small number of samples for useful analysis. Also the full scripts tend to show samples of all CPUs and all threads mixed up, which can be very confusing on larger systems. Add a new --samples option to save a small random number of samples per hist entry. Use a reservoir sample technique to select a representatve number of samples. Then allow browsing the samples using 'perf script' as part of the hist entry context menu. This automatically adds the right filters, so only the thread or cpu of the sample is displayed. Then we use less' search functionality to directly jump the to the time stamp of the selected sample. It uses different menus for assembler and source display. Assembler needs xed installed and source needs debuginfo. Currently it only supports as many samples as fit on the screen due to some limitations in the slang ui code. Signed-off-by: Andi Kleen <ak@linux.intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: http://lkml.kernel.org/r/20190311174605.GA29294@tassilo.jf.intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>