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Subject[PATCH V4 05/17] perf machine: Remove the indent in resolve_lbr_callchain_sample
Date
From: Kan Liang <kan.liang@linux.intel.com>

The indent is unnecessary in resolve_lbr_callchain_sample.
Removing it will make the following patch simpler.

Current code path for resolve_lbr_callchain_sample()

/* LBR only affects the user callchain */
if (i != chain_nr) {
body of the function
....
return 1;
}

return 0;

With the patch,

/* LBR only affects the user callchain */
if (i == chain_nr)
return 0;

body of the function
...
return 1;

No functional changes.

Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
---
tools/perf/util/machine.c | 123 +++++++++++++++++++-------------------
1 file changed, 63 insertions(+), 60 deletions(-)

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index fd14f1489802..9021e5b6a2a9 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -2177,6 +2177,12 @@ static int resolve_lbr_callchain_sample(struct thread *thread,
int chain_nr = min(max_stack, (int)chain->nr), i;
u8 cpumode = PERF_RECORD_MISC_USER;
u64 ip, branch_from = 0;
+ struct branch_stack *lbr_stack;
+ struct branch_entry *entries;
+ int lbr_nr, j, k;
+ bool branch;
+ struct branch_flags *flags;
+ int mix_chain_nr;

for (i = 0; i < chain_nr; i++) {
if (chain->ips[i] == PERF_CONTEXT_USER)
@@ -2184,71 +2190,68 @@ static int resolve_lbr_callchain_sample(struct thread *thread,
}

/* LBR only affects the user callchain */
- if (i != chain_nr) {
- struct branch_stack *lbr_stack = sample->branch_stack;
- struct branch_entry *entries = perf_sample__branch_entries(sample);
- int lbr_nr = lbr_stack->nr, j, k;
- bool branch;
- struct branch_flags *flags;
- /*
- * 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;
-
- for (j = 0; j < mix_chain_nr; j++) {
- int err;
- branch = false;
- flags = NULL;
+ if (i == chain_nr)
+ return 0;

- if (callchain_param.order == ORDER_CALLEE) {
- if (j < i + 1)
- ip = chain->ips[j];
- else if (j > i + 1) {
- k = j - i - 2;
- ip = entries[k].from;
- branch = true;
- flags = &entries[k].flags;
- } else {
- ip = entries[0].to;
- branch = true;
- flags = &entries[0].flags;
- branch_from = entries[0].from;
- }
+ lbr_stack = sample->branch_stack;
+ entries = perf_sample__branch_entries(sample);
+ 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
+ */
+ mix_chain_nr = i + 1 + lbr_nr + 1;
+
+ for (j = 0; j < mix_chain_nr; j++) {
+ int err;
+
+ branch = false;
+ flags = NULL;
+
+ if (callchain_param.order == ORDER_CALLEE) {
+ if (j < i + 1)
+ ip = chain->ips[j];
+ else if (j > i + 1) {
+ k = j - i - 2;
+ ip = entries[k].from;
+ branch = true;
+ flags = &entries[k].flags;
} else {
- if (j < lbr_nr) {
- k = lbr_nr - j - 1;
- ip = entries[k].from;
- branch = true;
- flags = &entries[k].flags;
- }
- else if (j > lbr_nr)
- ip = chain->ips[i + 1 - (j - lbr_nr)];
- else {
- ip = entries[0].to;
- branch = true;
- flags = &entries[0].flags;
- branch_from = entries[0].from;
- }
+ ip = entries[0].to;
+ branch = true;
+ flags = &entries[0].flags;
+ branch_from = entries[0].from;
+ }
+ } else {
+ if (j < lbr_nr) {
+ k = lbr_nr - j - 1;
+ ip = entries[k].from;
+ branch = true;
+ flags = &entries[k].flags;
+ } else if (j > lbr_nr)
+ ip = chain->ips[i + 1 - (j - lbr_nr)];
+ else {
+ ip = entries[0].to;
+ branch = true;
+ flags = &entries[0].flags;
+ branch_from = entries[0].from;
}
-
- err = add_callchain_ip(thread, cursor, parent,
- root_al, &cpumode, ip,
- branch, flags, NULL,
- branch_from);
- if (err)
- return (err < 0) ? err : 0;
}
- return 1;
- }

- return 0;
+ err = add_callchain_ip(thread, cursor, parent,
+ root_al, &cpumode, ip,
+ branch, flags, NULL,
+ branch_from);
+ if (err)
+ return (err < 0) ? err : 0;
+ }
+ return 1;
}

static int find_prev_cpumode(struct ip_callchain *chain, struct thread *thread,
--
2.17.1
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