return nr;
}
-static int thread__resolve_callchain_sample(struct thread *thread,
- struct ip_callchain *chain,
- struct branch_stack *branch,
- struct symbol **parent,
- struct addr_location *root_al,
- int max_stack)
+/*
+ * Recolve LBR callstack chain sample
+ * Return:
+ * 1 on success get LBR callchain information
+ * 0 no available LBR callchain information, should try fp
+ * negative error code on other errors.
+ */
+static int resolve_lbr_callchain_sample(struct thread *thread,
+ struct perf_sample *sample,
+ struct symbol **parent,
+ struct addr_location *root_al,
+ int max_stack)
{
+ struct ip_callchain *chain = sample->callchain;
+ int chain_nr = min(max_stack, (int)chain->nr);
+ int i, j, err;
+ u64 ip;
+
+ for (i = 0; i < chain_nr; i++) {
+ if (chain->ips[i] == PERF_CONTEXT_USER)
+ break;
+ }
+
+ /* LBR only affects the user callchain */
+ if (i != chain_nr) {
+ struct branch_stack *lbr_stack = sample->branch_stack;
+ int lbr_nr = lbr_stack->nr;
+ /*
+ * LBR callstack can only get user call chain.
+ * The mix_chain_nr is kernel call chain
+ * number plus LBR user call chain number.
+ * i is kernel call chain number,
+ * 1 is PERF_CONTEXT_USER,
+ * lbr_nr + 1 is the user call chain number.
+ * For details, please refer to the comments
+ * in callchain__printf
+ */
+ int mix_chain_nr = i + 1 + lbr_nr + 1;
+
+ if (mix_chain_nr > PERF_MAX_STACK_DEPTH + 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)
+ ip = chain->ips[j];
+ else if (j > i + 1)
+ ip = lbr_stack->entries[j - i - 2].from;
+ else
+ ip = lbr_stack->entries[0].to;
+ } else {
+ if (j < lbr_nr)
+ ip = lbr_stack->entries[lbr_nr - j - 1].from;
+ else if (j > lbr_nr)
+ ip = chain->ips[i + 1 - (j - lbr_nr)];
+ else
+ ip = lbr_stack->entries[0].to;
+ }
+
+ err = add_callchain_ip(thread, parent, root_al, false, ip);
+ if (err)
+ return (err < 0) ? err : 0;
+ }
+ return 1;
+ }
+
+ return 0;
+}
+
+static int thread__resolve_callchain_sample(struct thread *thread,
+ struct perf_evsel *evsel,
+ struct perf_sample *sample,
+ struct symbol **parent,
+ struct addr_location *root_al,
+ int max_stack)
+{
+ struct branch_stack *branch = sample->branch_stack;
+ struct ip_callchain *chain = sample->callchain;
int chain_nr = min(max_stack, (int)chain->nr);
int i, j, err;
int skip_idx = -1;
int first_call = 0;
+ callchain_cursor_reset(&callchain_cursor);
+
+ if (has_branch_callstack(evsel)) {
+ err = resolve_lbr_callchain_sample(thread, sample, parent,
+ root_al, max_stack);
+ if (err)
+ return (err < 0) ? err : 0;
+ }
+
/*
* Based on DWARF debug information, some architectures skip
* a callchain entry saved by the kernel.
if (chain->nr < PERF_MAX_STACK_DEPTH)
skip_idx = arch_skip_callchain_idx(thread, chain);
- callchain_cursor_reset(&callchain_cursor);
-
/*
* Add branches to call stack for easier browsing. This gives
* more context for a sample than just the callers.
struct addr_location *root_al,
int max_stack)
{
- int ret = thread__resolve_callchain_sample(thread, sample->callchain,
- sample->branch_stack,
- parent, root_al, max_stack);
+ int ret = thread__resolve_callchain_sample(thread, evsel,
+ sample, parent,
+ root_al, max_stack);
if (ret)
return ret;
return 0;
}
-static void callchain__printf(struct perf_sample *sample)
+static void callchain__lbr_callstack_printf(struct perf_sample *sample)
{
+ struct ip_callchain *callchain = sample->callchain;
+ struct branch_stack *lbr_stack = sample->branch_stack;
+ u64 kernel_callchain_nr = callchain->nr;
unsigned int i;
- printf("... chain: nr:%" PRIu64 "\n", sample->callchain->nr);
+ for (i = 0; i < kernel_callchain_nr; i++) {
+ if (callchain->ips[i] == PERF_CONTEXT_USER)
+ break;
+ }
+
+ if ((i != kernel_callchain_nr) && lbr_stack->nr) {
+ u64 total_nr;
+ /*
+ * LBR callstack can only get user call chain,
+ * i is kernel call chain number,
+ * 1 is PERF_CONTEXT_USER.
+ *
+ * The user call chain is stored in LBR registers.
+ * LBR are pair registers. The caller is stored
+ * in "from" register, while the callee is stored
+ * in "to" register.
+ * For example, there is a call stack
+ * "A"->"B"->"C"->"D".
+ * The LBR registers will recorde like
+ * "C"->"D", "B"->"C", "A"->"B".
+ * So only the first "to" register and all "from"
+ * registers are needed to construct the whole stack.
+ */
+ total_nr = i + 1 + lbr_stack->nr + 1;
+ kernel_callchain_nr = i + 1;
+
+ printf("... LBR call chain: nr:%" PRIu64 "\n", total_nr);
+
+ for (i = 0; i < kernel_callchain_nr; i++)
+ printf("..... %2d: %016" PRIx64 "\n",
+ i, callchain->ips[i]);
+
+ printf("..... %2d: %016" PRIx64 "\n",
+ (int)(kernel_callchain_nr), lbr_stack->entries[0].to);
+ for (i = 0; i < lbr_stack->nr; i++)
+ printf("..... %2d: %016" PRIx64 "\n",
+ (int)(i + kernel_callchain_nr + 1), lbr_stack->entries[i].from);
+ }
+}
+
+static void callchain__printf(struct perf_evsel *evsel,
+ struct perf_sample *sample)
+{
+ unsigned int i;
+ struct ip_callchain *callchain = sample->callchain;
+
+ if (has_branch_callstack(evsel))
+ callchain__lbr_callstack_printf(sample);
+
+ printf("... FP chain: nr:%" PRIu64 "\n", callchain->nr);
- for (i = 0; i < sample->callchain->nr; i++)
+ for (i = 0; i < callchain->nr; i++)
printf("..... %2d: %016" PRIx64 "\n",
- i, sample->callchain->ips[i]);
+ i, callchain->ips[i]);
}
static void branch_stack__printf(struct perf_sample *sample)
sample_type = evsel->attr.sample_type;
if (sample_type & PERF_SAMPLE_CALLCHAIN)
- callchain__printf(sample);
+ callchain__printf(evsel, sample);
- if (sample_type & PERF_SAMPLE_BRANCH_STACK)
+ if ((sample_type & PERF_SAMPLE_BRANCH_STACK) && !has_branch_callstack(evsel))
branch_stack__printf(sample);
if (sample_type & PERF_SAMPLE_REGS_USER)
projects / cascardo / linux.git / commitdiff