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perf callchain: Stop validating callchains by the max_stack sysctl 

As thread__resolve_callchain_sample can be used for handling perf.data
files, that could've been recorded with a large max_stack sysctl setting
than what the system used for analysis has set.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/n/tip-2995bt2g5yq2m05vga4kip6m@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
hifive-unleashed-5.1
Arnaldo Carvalho de Melo 2016-05-19 11:14:15 -03:00
parent c008f78f93
commit bf8bddbf19
1 changed files with 5 additions and 20 deletions
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25
tools/perf/util/machine.c
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@ -1771,11 +1771,6 @@ static int resolve_lbr_callchain_sample(struct thread *thread,
*/
int mix_chain_nr = i + 1 + lbr_nr + 1;
if (mix_chain_nr > (int)sysctl_perf_event_max_stack + PERF_MAX_BRANCH_DEPTH) {
pr_warning("corrupted callchain. skipping...\n");
return 0;
}
for (j = 0; j < mix_chain_nr; j++) {
if (callchain_param.order == ORDER_CALLEE) {
if (j < i + 1)
@ -1815,7 +1810,7 @@ static int thread__resolve_callchain_sample(struct thread *thread,
struct ip_callchain *chain = sample->callchain;
int chain_nr = chain->nr;
u8 cpumode = PERF_RECORD_MISC_USER;
int i, j, err, nr_entries, nr_contexts;
int i, j, err, nr_entries;
int skip_idx = -1;
int first_call = 0;
@ -1830,8 +1825,7 @@ static int thread__resolve_callchain_sample(struct thread *thread,
* Based on DWARF debug information, some architectures skip
* a callchain entry saved by the kernel.
*/
if (chain_nr < sysctl_perf_event_max_stack)
skip_idx = arch_skip_callchain_idx(thread, chain);
skip_idx = arch_skip_callchain_idx(thread, chain);
/*
* Add branches to call stack for easier browsing. This gives
@ -1891,7 +1885,7 @@ static int thread__resolve_callchain_sample(struct thread *thread,
}
check_calls:
for (i = first_call, nr_entries = 0, nr_contexts = 0;
for (i = first_call, nr_entries = 0;
i < chain_nr && nr_entries < max_stack; i++) {
u64 ip;
@ -1906,13 +1900,8 @@ check_calls:
#endif
ip = chain->ips[j];
if (ip >= PERF_CONTEXT_MAX) {
if (++nr_contexts > sysctl_perf_event_max_contexts_per_stack)
goto out_corrupted_callchain;
} else {
if (++nr_entries > sysctl_perf_event_max_stack)
goto out_corrupted_callchain;
}
if (ip < PERF_CONTEXT_MAX)
++nr_entries;
err = add_callchain_ip(thread, cursor, parent, root_al, &cpumode, ip);
@ -1921,10 +1910,6 @@ check_calls:
}
return 0;
out_corrupted_callchain:
pr_warning("corrupted callchain. skipping...\n");
return 0;
}
static int unwind_entry(struct unwind_entry *entry, void *arg)