Skip to content

Commit

Permalink
perf tools: Fix hybrid config terms list corruption
Browse files Browse the repository at this point in the history 
A config terms list was spliced twice, resulting in a never-ending loop
when the list was traversed. Fix by using list_splice_init() and copying
and freeing the lists as necessary.

This patch also depends on patch "perf tools: Factor out
copy_config_terms() and free_config_terms()"

Example on ADL:

 Before:

  # perf record -e '{intel_pt//,cycles/aux-sample-size=4096/pp}' uname &
  # jobs
  [1]+  Running                    perf record -e "{intel_pt//,cycles/aux-sample-size=4096/pp}" uname
  # perf top -E 10
    PerfTop:    4071 irqs/sec  kernel: 6.9%  exact: 100.0% lost: 0/0 drop: 0/0 [4000Hz cycles],  (all, 24 CPUs)
  ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    97.60%  perf           [.] __evsel__get_config_term
     0.25%  [kernel]       [k] kallsyms_expand_symbol.constprop.13
     0.24%  perf           [.] kallsyms__parse
     0.15%  [kernel]       [k] _raw_spin_lock
     0.14%  [kernel]       [k] number
     0.13%  [kernel]       [k] advance_transaction
     0.08%  [kernel]       [k] format_decode
     0.08%  perf           [.] map__process_kallsym_symbol
     0.08%  perf           [.] rb_insert_color
     0.08%  [kernel]       [k] vsnprintf
  exiting.
  # kill %1

After:

  # perf record -e '{intel_pt//,cycles/aux-sample-size=4096/pp}' uname &
  Linux
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.060 MB perf.data ]
  # perf script | head
       perf-exec   604 [001]  1827.312293:                            psb:  psb offs: 0                       ffffffffb8415e87 pt_config_start+0x37 ([kernel.kallsyms])
       perf-exec   604  1827.312293:          1                       branches:  ffffffffb856a3bd event_sched_in.isra.133+0xfd ([kernel.kallsyms]) => ffffffffb856a9a0 perf_pmu_nop_void+0x0 ([kernel.kallsyms])
       perf-exec   604  1827.312293:          1                       branches:  ffffffffb856b10e merge_sched_in+0x26e ([kernel.kallsyms]) => ffffffffb856a2c0 event_sched_in.isra.133+0x0 ([kernel.kallsyms])
       perf-exec   604  1827.312293:          1                       branches:  ffffffffb856a45d event_sched_in.isra.133+0x19d ([kernel.kallsyms]) => ffffffffb8568b80 perf_event_set_state.part.61+0x0 ([kernel.kallsyms])
       perf-exec   604  1827.312293:          1                       branches:  ffffffffb8568b86 perf_event_set_state.part.61+0x6 ([kernel.kallsyms]) => ffffffffb85662a0 perf_event_update_time+0x0 ([kernel.kallsyms])
       perf-exec   604  1827.312293:          1                       branches:  ffffffffb856a35c event_sched_in.isra.133+0x9c ([kernel.kallsyms]) => ffffffffb8567610 perf_log_itrace_start+0x0 ([kernel.kallsyms])
       perf-exec   604  1827.312293:          1                       branches:  ffffffffb856a377 event_sched_in.isra.133+0xb7 ([kernel.kallsyms]) => ffffffffb8403b40 x86_pmu_add+0x0 ([kernel.kallsyms])
       perf-exec   604  1827.312293:          1                       branches:  ffffffffb8403b86 x86_pmu_add+0x46 ([kernel.kallsyms]) => ffffffffb8403940 collect_events+0x0 ([kernel.kallsyms])
       perf-exec   604  1827.312293:          1                       branches:  ffffffffb8403a7b collect_events+0x13b ([kernel.kallsyms]) => ffffffffb8402cd0 collect_event+0x0 ([kernel.kallsyms])

Fixes: 30def61 ("perf parse-events Create two hybrid cache events")
Fixes: 94da591 ("perf parse-events Create two hybrid raw events")
Fixes: 9cbfa2f ("perf parse-events Create two hybrid hardware events")
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Jin Yao <[email protected]>
Cc: Kan Liang <[email protected]>
Link: https //lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
  • Loading branch information
@ahunter6 @acmel
ahunter6 authored and acmel committed Sep 11, 2021
1 parent a7d212f commit 99fc594
Show file tree
Hide file tree
Showing 2 changed files with 27 additions and 9 deletions.
18 changes: 15 additions & 3 deletions tools/perf/util/parse-events-hybrid.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -76,12 +76,16 @@ static int add_hw_hybrid(struct parse_events_state *parse_state,
int ret;

perf_pmu__for_each_hybrid_pmu(pmu) {
LIST_HEAD(terms);

if (pmu_cmp(parse_state, pmu))
continue;

copy_config_terms(&terms, config_terms);
ret = create_event_hybrid(PERF_TYPE_HARDWARE,
&parse_state->idx, list, attr, name,
config_terms, pmu);
&terms, pmu);
free_config_terms(&terms);
if (ret)
return ret;
}
Expand Down Expand Up @@ -115,11 +119,15 @@ static int add_raw_hybrid(struct parse_events_state *parse_state,
int ret;

perf_pmu__for_each_hybrid_pmu(pmu) {
LIST_HEAD(terms);

if (pmu_cmp(parse_state, pmu))
continue;

copy_config_terms(&terms, config_terms);
ret = create_raw_event_hybrid(&parse_state->idx, list, attr,
name, config_terms, pmu);
name, &terms, pmu);
free_config_terms(&terms);
if (ret)
return ret;
}
Expand Down Expand Up @@ -165,11 +173,15 @@ int parse_events__add_cache_hybrid(struct list_head *list, int *idx,

*hybrid = true;
perf_pmu__for_each_hybrid_pmu(pmu) {
LIST_HEAD(terms);

if (pmu_cmp(parse_state, pmu))
continue;

copy_config_terms(&terms, config_terms);
ret = create_event_hybrid(PERF_TYPE_HW_CACHE, idx, list,
attr, name, config_terms, pmu);
attr, name, &terms, pmu);
free_config_terms(&terms);
if (ret)
return ret;
}
Expand Down
18 changes: 12 additions & 6 deletions tools/perf/util/parse-events.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -387,7 +387,7 @@ __add_event(struct list_head *list, int *idx,
evsel->name = strdup(name);

if (config_terms)
list_splice(config_terms, &evsel->config_terms);
list_splice_init(config_terms, &evsel->config_terms);

if (list)
list_add_tail(&evsel->core.node, list);
Expand Down Expand Up @@ -535,9 +535,12 @@ int parse_events_add_cache(struct list_head *list, int *idx,
config_name ? : name, &config_terms,
&hybrid, parse_state);
if (hybrid)
return ret;
goto out_free_terms;

return add_event(list, idx, &attr, config_name ? : name, &config_terms);
ret = add_event(list, idx, &attr, config_name ? : name, &config_terms);
out_free_terms:
free_config_terms(&config_terms);
return ret;
}

static void tracepoint_error(struct parse_events_error *e, int err,
Expand Down Expand Up @@ -1457,10 +1460,13 @@ int parse_events_add_numeric(struct parse_events_state *parse_state,
get_config_name(head_config),
&config_terms, &hybrid);
if (hybrid)
return ret;
goto out_free_terms;

return add_event(list, &parse_state->idx, &attr,
get_config_name(head_config), &config_terms);
ret = add_event(list, &parse_state->idx, &attr,
get_config_name(head_config), &config_terms);
out_free_terms:
free_config_terms(&config_terms);
return ret;
}

int parse_events_add_tool(struct parse_events_state *parse_state,
Expand Down

0 comments on commit 99fc594

Please sign in to comment.