Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758452AbbKSLWk (ORCPT ); Thu, 19 Nov 2015 06:22:40 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42077 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758430AbbKSLWi (ORCPT ); Thu, 19 Nov 2015 06:22:38 -0500 Date: Thu, 19 Nov 2015 12:22:34 +0100 From: Jiri Olsa To: Jiri Olsa Cc: Arnaldo Carvalho de Melo , Jan Kratochvil , lkml , David Ahern , Peter Zijlstra , Ingo Molnar , Namhyung Kim , Milian Wolff , Wang Nan Subject: [PATCH 4/3] perf tools: Add callchain order support for libdw DWARF unwinder Message-ID: <20151119112218.GA12585@krava.local> References: <1447772739-18471-1-git-send-email-jolsa@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1447772739-18471-1-git-send-email-jolsa@kernel.org> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5749 Lines: 213 On Tue, Nov 17, 2015 at 04:05:36PM +0100, Jiri Olsa wrote: SNIP > Tested on x86_64. The change is in generic code only, > so it should not affect other archs. Still it would be > nice to have some confirmation.. Wang Nan? ;-) > > It'd be nice to have this for libdw unwind as well, > but it looks like it's out of reach for perf code.. Jan? > > Also available in: > git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git > perf/callchain_1 adding also libdw support.. test with 'make NO_LIBUNWIND=1' Also available in: git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git perf/callchain_3 thanks, jirka --- As reported by Milian, currently for DWARF unwind (both libdw and libunwind) we display callchain in callee order only. Adding the support to follow callchain order setup to libdw DWARF unwinder, so we could get following output for report: $ perf record --call-graph dwarf ls ... $ perf report --no-children --stdio 13.63% ls [kernel.vmlinux] [k] __rb_insert_augmented | ---__rb_insert_augmented __vma_link_rb vma_link do_brk vm_brk load_elf_binary search_binary_handler do_execveat_common.isra.29 sys_execve return_from_execve $ perf report --stdio --no-children -g caller 13.63% ls [kernel.vmlinux] [k] __rb_insert_augmented | ---return_from_execve sys_execve do_execveat_common.isra.29 search_binary_handler load_elf_binary vm_brk do_brk vma_link __vma_link_rb __rb_insert_augmented Reported-by: Milian Wolff Link: http://lkml.kernel.org/n/tip-zk99ay9s71whl9qd9if28u8z@git.kernel.org Signed-off-by: Jiri Olsa --- tools/perf/util/unwind-libdw.c | 53 ++++++++++++++++++++++++++++++------------ tools/perf/util/unwind-libdw.h | 2 ++ 2 files changed, 40 insertions(+), 15 deletions(-) diff --git a/tools/perf/util/unwind-libdw.c b/tools/perf/util/unwind-libdw.c index 2dcfe9a7c8d0..db8142ba7cb9 100644 --- a/tools/perf/util/unwind-libdw.c +++ b/tools/perf/util/unwind-libdw.c @@ -11,6 +11,7 @@ #include #include "event.h" #include "perf_regs.h" +#include "callchain.h" static char *debuginfo_path; @@ -52,25 +53,28 @@ static int report_module(u64 ip, struct unwind_info *ui) return __report_module(&al, ip, ui); } +/* + * Store all entries within entries array, + * we will process it after we finish unwind. + */ static int entry(u64 ip, struct unwind_info *ui) { - struct unwind_entry e; + struct unwind_entry *e = &ui->entries[ui->idx++]; struct addr_location al; if (__report_module(&al, ip, ui)) return -1; - e.ip = ip; - e.map = al.map; - e.sym = al.sym; + e->ip = ip; + e->map = al.map; + e->sym = al.sym; pr_debug("unwind: %s:ip = 0x%" PRIx64 " (0x%" PRIx64 ")\n", al.sym ? al.sym->name : "''", ip, al.map ? al.map->map_ip(al.map, ip) : (u64) 0); - - return ui->cb(&e, ui->arg); + return 0; } static pid_t next_thread(Dwfl *dwfl, void *arg, void **thread_argp) @@ -168,7 +172,7 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg, struct perf_sample *data, int max_stack) { - struct unwind_info ui = { + struct unwind_info *ui, ui_buf = { .sample = data, .thread = thread, .machine = thread->mg->machine, @@ -177,35 +181,54 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg, .max_stack = max_stack, }; Dwarf_Word ip; - int err = -EINVAL; + int err = -EINVAL, i; if (!data->user_regs.regs) return -EINVAL; - ui.dwfl = dwfl_begin(&offline_callbacks); - if (!ui.dwfl) + ui = zalloc(sizeof(ui_buf) + sizeof(ui_buf.entries[0]) * max_stack); + if (!ui) + return -ENOMEM; + + *ui = ui_buf; + + ui->dwfl = dwfl_begin(&offline_callbacks); + if (!ui->dwfl) goto out; err = perf_reg_value(&ip, &data->user_regs, PERF_REG_IP); if (err) goto out; - err = report_module(ip, &ui); + err = report_module(ip, ui); if (err) goto out; - if (!dwfl_attach_state(ui.dwfl, EM_NONE, thread->tid, &callbacks, &ui)) + if (!dwfl_attach_state(ui->dwfl, EM_NONE, thread->tid, &callbacks, ui)) goto out; - err = dwfl_getthread_frames(ui.dwfl, thread->tid, frame_callback, &ui); + err = dwfl_getthread_frames(ui->dwfl, thread->tid, frame_callback, ui); - if (err && !ui.max_stack) + if (err && !ui->max_stack) err = 0; + /* + * Display what we got based on the order setup. + */ + for (i = 0; i < ui->idx && !err; i++) { + int j = i; + + if (callchain_param.order == ORDER_CALLER) + j = ui->idx - i - 1; + + err = ui->entries[j].ip ? ui->cb(&ui->entries[j], ui->arg) : 0; + } + out: if (err) pr_debug("unwind: failed with '%s'\n", dwfl_errmsg(-1)); - dwfl_end(ui.dwfl); + dwfl_end(ui->dwfl); + free(ui); return 0; } diff --git a/tools/perf/util/unwind-libdw.h b/tools/perf/util/unwind-libdw.h index 417a1426f3ad..58328669ed16 100644 --- a/tools/perf/util/unwind-libdw.h +++ b/tools/perf/util/unwind-libdw.h @@ -16,6 +16,8 @@ struct unwind_info { unwind_entry_cb_t cb; void *arg; int max_stack; + int idx; + struct unwind_entry entries[]; }; #endif /* __PERF_UNWIND_LIBDW_H */ -- 2.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/