From 71ad0f5e4e361c8bca864c7d09d14b64af6bc2fc Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 7 Aug 2012 15:20:46 +0200 Subject: perf tools: Support for DWARF CFI unwinding on post processing This brings the support for DWARF cfi unwinding on perf post processing. Call frame informations are retrieved and then passed to libunwind that requests memory and register content from the applications. Adding unwind object to handle the user stack backtrace based on the user register values and user stack dump. The unwind object access the libunwind via remote interface and provides to it all the necessary data to unwind the stack. The unwind interface provides following function: unwind__get_entries And callback (specified in above function) to retrieve the backtrace entries: typedef int (*unwind_entry_cb_t)(struct unwind_entry *entry, void *arg); Signed-off-by: Jiri Olsa Original-patch-by: Frederic Weisbecker Cc: "Frank Ch. Eigler" Cc: Arun Sharma Cc: Benjamin Redelings Cc: Corey Ashford Cc: Cyrill Gorcunov Cc: Frank Ch. Eigler Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Masami Hiramatsu Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Robert Richter Cc: Stephane Eranian Cc: Tom Zanussi Cc: Ulrich Drepper Link: http://lkml.kernel.org/r/1344345647-11536-12-git-send-email-jolsa@redhat.com [ Replaced use of perf_session by usage of perf_evsel ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/session.c | 66 +++++++++++++++++++++++++++++++++++++---------- 1 file changed, 53 insertions(+), 13 deletions(-) (limited to 'tools/perf/util/session.c') diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index c9ed7e3cf23..f7bb7ae328d 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -16,6 +16,7 @@ #include "cpumap.h" #include "event-parse.h" #include "perf_regs.h" +#include "unwind.h" static int perf_session__open(struct perf_session *self, bool force) { @@ -289,10 +290,11 @@ struct branch_info *machine__resolve_bstack(struct machine *self, return bi; } -int machine__resolve_callchain(struct machine *self, - struct thread *thread, - struct ip_callchain *chain, - struct symbol **parent) +static int machine__resolve_callchain_sample(struct machine *machine, + struct thread *thread, + struct ip_callchain *chain, + struct symbol **parent) + { u8 cpumode = PERF_RECORD_MISC_USER; unsigned int i; @@ -317,11 +319,14 @@ int machine__resolve_callchain(struct machine *self, if (ip >= PERF_CONTEXT_MAX) { switch (ip) { case PERF_CONTEXT_HV: - cpumode = PERF_RECORD_MISC_HYPERVISOR; break; + cpumode = PERF_RECORD_MISC_HYPERVISOR; + break; case PERF_CONTEXT_KERNEL: - cpumode = PERF_RECORD_MISC_KERNEL; break; + cpumode = PERF_RECORD_MISC_KERNEL; + break; case PERF_CONTEXT_USER: - cpumode = PERF_RECORD_MISC_USER; break; + cpumode = PERF_RECORD_MISC_USER; + break; default: pr_debug("invalid callchain context: " "%"PRId64"\n", (s64) ip); @@ -336,7 +341,7 @@ int machine__resolve_callchain(struct machine *self, } al.filtered = false; - thread__find_addr_location(thread, self, cpumode, + thread__find_addr_location(thread, machine, cpumode, MAP__FUNCTION, ip, &al, NULL); if (al.sym != NULL) { if (sort__has_parent && !*parent && @@ -355,6 +360,40 @@ int machine__resolve_callchain(struct machine *self, return 0; } +static int unwind_entry(struct unwind_entry *entry, void *arg) +{ + struct callchain_cursor *cursor = arg; + return callchain_cursor_append(cursor, entry->ip, + entry->map, entry->sym); +} + +int machine__resolve_callchain(struct machine *machine, + struct perf_evsel *evsel, + struct thread *thread, + struct perf_sample *sample, + struct symbol **parent) + +{ + int ret; + + callchain_cursor_reset(&callchain_cursor); + + ret = machine__resolve_callchain_sample(machine, thread, + sample->callchain, parent); + if (ret) + return ret; + + /* Can we do dwarf post unwind? */ + if (!((evsel->attr.sample_type & PERF_SAMPLE_REGS_USER) && + (evsel->attr.sample_type & PERF_SAMPLE_STACK_USER))) + return 0; + + return unwind__get_entries(unwind_entry, &callchain_cursor, machine, + thread, evsel->attr.sample_regs_user, + sample); + +} + static int process_event_synth_tracing_data_stub(union perf_event *event __used, struct perf_session *session __used) { @@ -1533,9 +1572,9 @@ struct perf_evsel *perf_session__find_first_evtype(struct perf_session *session, return NULL; } -void perf_event__print_ip(union perf_event *event, struct perf_sample *sample, - struct machine *machine, int print_sym, - int print_dso, int print_symoffset) +void perf_evsel__print_ip(struct perf_evsel *evsel, union perf_event *event, + struct perf_sample *sample, struct machine *machine, + int print_sym, int print_dso, int print_symoffset) { struct addr_location al; struct callchain_cursor_node *node; @@ -1549,8 +1588,9 @@ void perf_event__print_ip(union perf_event *event, struct perf_sample *sample, if (symbol_conf.use_callchain && sample->callchain) { - if (machine__resolve_callchain(machine, al.thread, - sample->callchain, NULL) != 0) { + + if (machine__resolve_callchain(machine, evsel, al.thread, + sample, NULL) != 0) { if (verbose) error("Failed to resolve callchain. Skipping\n"); return; -- cgit v1.2.3-70-g09d2