[PATCH V7 17/18] tools/perf: Update data_type_cmp and sort__typeoff_sort function to include var_name in comparison
From: Athira Rajeev <hidden>
Date: 2024-07-13 16:56:48
Also in:
linux-perf-users, lkml
Subsystem:
performance events subsystem, the rest · Maintainers:
Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
Currently data_type_cmp() only compares size and type name.
But in cases where the type name of two data type entries
is same, but var_name is different, the comparison can't distinguish
two different types.
Consider there is a "long unsigned int" with var_name as "X" and there
is global variable "long unsigned int". Currently since
data_type_cmp uses only type_name for comparison ( "long unsigned int"),
it won't distinguish these as separate entries. Update the
functions "data_type_cmp" as well as "sort__typeoff_sort" to
compare variable names after type name if it exists. Inorder to
use cmp_null, make the cmp_null from sort.c as not static.
Also updated "hist_entry__typeoff_snprintf" to print var_name if
it is set. With the changes,
11.42% long unsigned int long unsigned int +0 (current_stack_pointer)
4.68% struct paca_struct struct paca_struct +2312 (__current)
4.57% struct paca_struct struct paca_struct +2354 (irq_soft_mask)
2.69% struct paca_struct struct paca_struct +2808 (canary)
2.68% struct paca_struct struct paca_struct +8 (paca_index)
2.24% struct paca_struct struct paca_struct +48 (data_offset)
1.43% long unsigned int long unsigned int +0 (no field)
Using ./perf report -s type,typeoff -H:
17.65% struct paca_struct
4.68% struct paca_struct +2312 (__current)
4.57% struct paca_struct +2354 (irq_soft_mask)
2.69% struct paca_struct +2808 (canary)
2.68% struct paca_struct +8 (paca_index)
2.24% struct paca_struct +48 (data_offset)
0.55% struct paca_struct +2816 (mmiowb_state.nesting_count)
0.18% struct paca_struct +2818 (mmiowb_state.mmiowb_pending)
0.03% struct paca_struct +2352 (hsrr_valid)
0.02% struct paca_struct +2356 (irq_work_pending)
0.00% struct paca_struct +0 (lppaca_ptr)
12.85% long unsigned int
11.42% long unsigned int +0 (current_stack_pointer)
1.43% long unsigned int +0 (no field)
With perf report -s type:
17.65% struct paca_struct
12.85% long unsigned int
1.69% struct task_struct
1.51% struct rq
with perf report -s typeoff
11.42% long unsigned int +0 (current_stack_pointer)
4.68% struct paca_struct +2312 (__current)
4.57% struct paca_struct +2354 (irq_soft_mask)
2.69% struct paca_struct +2808 (canary)
2.68% struct paca_struct +8 (paca_index)
2.24% struct paca_struct +48 (data_offset)
1.43% long unsigned int +0 (no field)
Signed-off-by: Athira Rajeev <redacted>
---
tools/perf/util/annotate-data.c | 23 +++++++++++++++++++++--
tools/perf/util/sort.c | 25 ++++++++++++++++++++++---
tools/perf/util/sort.h | 1 +
3 files changed, 44 insertions(+), 5 deletions(-)
diff --git a/tools/perf/util/annotate-data.c b/tools/perf/util/annotate-data.c
index 8d05f3dbddf6..ea69c8d3d856 100644
--- a/tools/perf/util/annotate-data.c
+++ b/tools/perf/util/annotate-data.c@@ -167,7 +167,7 @@ static void exit_type_state(struct type_state *state) } /* - * Compare type name and size to maintain them in a tree. + * Compare type name, var_name and size to maintain them in a tree. * I'm not sure if DWARF would have information of a single type in many * different places (compilation units). If not, it could compare the * offset of the type entry in the .debug_info section.
@@ -176,12 +176,31 @@ static int data_type_cmp(const void *_key, const struct rb_node *node) { const struct annotated_data_type *key = _key; struct annotated_data_type *type; + int64_t ret = 0; type = rb_entry(node, struct annotated_data_type, node); if (key->self.size != type->self.size) return key->self.size - type->self.size; - return strcmp(key->self.type_name, type->self.type_name); + + ret = strcmp(key->self.type_name, type->self.type_name); + if (ret) + return ret; + + /* + * Compare var_name if it exists for key and type. + * If both nodes doesn't have var_name, but one of + * them has, return non-zero. This is to indicate nodes + * are not the same if one has var_name, but other doesn't. + */ + if (key->self.var_name && type->self.var_name) { + ret = strcmp(key->self.var_name, type->self.var_name); + if (ret) + return ret; + } else if (!key->self.var_name != !type->self.var_name) + return cmp_null(key->self.var_name, type->self.var_name); + + return ret; } static bool data_type_less(struct rb_node *node_a, const struct rb_node *node_b)
diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index cd39ea972193..25761d01dbd0 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c@@ -95,7 +95,7 @@ static int repsep_snprintf(char *bf, size_t size, const char *fmt, ...) return n; } -static int64_t cmp_null(const void *l, const void *r) +int64_t cmp_null(const void *l, const void *r) { if (!l && !r) return 0;
@@ -2267,9 +2267,25 @@ sort__typeoff_sort(struct hist_entry *left, struct hist_entry *right) right_type = right->mem_type; } + /* + * Compare type_name first. Next, ompare var_name if it exists + * for left and right hist_entry. If both entries doesn't have + * var_name, but one of them has, return non-zero. This is to + * indicate entries are not the same if one has var_name, but the + * other doesn't. + * If type_name and var_name is same, use mem_type_off field. + */ ret = strcmp(left_type->self.type_name, right_type->self.type_name); if (ret) return ret; + + if (left_type->self.var_name && right_type->self.var_name) { + ret = strcmp(left_type->self.var_name, right_type->self.var_name); + if (ret) + return ret; + } else if (!left_type->self.var_name != !right_type->self.var_name) + return cmp_null(left_type->self.var_name, right_type->self.var_name); + return left->mem_type_off - right->mem_type_off; }
@@ -2305,9 +2321,12 @@ static int hist_entry__typeoff_snprintf(struct hist_entry *he, char *bf, char buf[4096]; buf[0] = '\0'; - if (list_empty(&he_type->self.children)) + if (list_empty(&he_type->self.children)) { snprintf(buf, sizeof(buf), "no field"); - else + if (he_type->self.var_name) + strcpy(buf, he_type->self.var_name); + + } else fill_member_name(buf, sizeof(buf), &he_type->self, he->mem_type_off, true); buf[4095] = '\0';
diff --git a/tools/perf/util/sort.h b/tools/perf/util/sort.h
index 0bd0ee3ae76b..41346d2b940e 100644
--- a/tools/perf/util/sort.h
+++ b/tools/perf/util/sort.h@@ -151,4 +151,5 @@ sort__dcacheline_cmp(struct hist_entry *left, struct hist_entry *right); int64_t _sort__sym_cmp(struct symbol *sym_l, struct symbol *sym_r); char *hist_entry__srcline(struct hist_entry *he); +int64_t cmp_null(const void *l, const void *r); #endif /* __PERF_SORT_H */
--
2.43.0