From d3678758048308049cdad31ec3eae063be17c0db Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 21 Dec 2010 23:38:37 -0200 Subject: [PATCH] perf test: Look forward for symbol aliases Not just before, fixing these false positives: [acme@mica linux]$ perf test -v 1 1: vmlinux symtab matches kallsyms: --- start --- Looking at the vmlinux_path (6 entries long) Using //lib/modules/2.6.37-rc5-00180-ge06b6bf/build/vmlinux for symbols 0xffffffff81058dc0: diff name v: sys_vm86old k: sys_ni_syscall 0xffffffff81058dc0: diff name v: sys_vm86 k: sys_ni_syscall 0xffffffff81058dc0: diff name v: sys_subpage_prot k: sys_ni_syscall 0xffffffff810b5f7c: diff name v: probe_kernel_write k: __probe_kernel_write 0xffffffff810b5fe5: diff name v: probe_kernel_read k: __probe_kernel_read 0xffffffff811bc380: diff name v: __memset k: memset 0xffffffff81384a98: diff name v: __sched_text_start k: sleep_on_common 0xffffffff81386750: diff name v: __sched_text_end k: _raw_spin_trylock 0xffffffff8138cee8: diff name v: __irqentry_text_start k: do_IRQ 0xffffffff8138f079: diff name v: __start_notes k: _etext 0xffffffff8138f079: diff name v: __stop_notes k: _etext ---- end ---- vmlinux symtab matches kallsyms: FAILED! [acme@mica linux]$ Some are weak functions, others are just markers, etc. They get in the rb tree with the same addr, so we need to look around to find the symbol with the same name. We were looking just at the previous entries with the same addr, look forward too. Cc: Frederic Weisbecker Cc: Han Pingtian Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Paul Mackerras Cc: Stephane Eranian LKML-Reference: Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-test.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/tools/perf/builtin-test.c b/tools/perf/builtin-test.c index 035b9fa063a9..e0c3f471f22d 100644 --- a/tools/perf/builtin-test.c +++ b/tools/perf/builtin-test.c @@ -119,10 +119,16 @@ static int test__vmlinux_matches_kallsyms(void) * end addresses too. */ for (nd = rb_first(&vmlinux_map->dso->symbols[type]); nd; nd = rb_next(nd)) { - struct symbol *pair; + struct symbol *pair, *first_pair; + bool backwards = true; sym = rb_entry(nd, struct symbol, rb_node); - pair = machine__find_kernel_symbol(&kallsyms, type, sym->start, NULL, NULL); + + if (sym->start == sym->end) + continue; + + first_pair = machine__find_kernel_symbol(&kallsyms, type, sym->start, NULL, NULL); + pair = first_pair; if (pair && pair->start == sym->start) { next_pair: @@ -143,8 +149,10 @@ static int test__vmlinux_matches_kallsyms(void) pr_debug("%#Lx: diff end addr for %s v: %#Lx k: %#Lx\n", sym->start, sym->name, sym->end, pair->end); } else { - struct rb_node *nnd = rb_prev(&pair->rb_node); - + struct rb_node *nnd; +detour: + nnd = backwards ? rb_prev(&pair->rb_node) : + rb_next(&pair->rb_node); if (nnd) { struct symbol *next = rb_entry(nnd, struct symbol, rb_node); @@ -153,6 +161,13 @@ static int test__vmlinux_matches_kallsyms(void) goto next_pair; } } + + if (backwards) { + backwards = false; + pair = first_pair; + goto detour; + } + pr_debug("%#Lx: diff name v: %s k: %s\n", sym->start, sym->name, pair->name); } -- GitLab