Re: [PATCH v7] perf stat: Fix wrong skipping for per-die aggregation

[Jiri Olsa]

On Thu, Jan 21, 2021 at 12:21:36PM +0800, Jin, Yao wrote:

sNIP

> mask = hashmap__new(pkg_id_hash, pkg_id_equal, NULL);
> d = cpu_map__get_die(cpus, cpu, NULL).die;
> key = (size_t)d << KEY_SHIFT | s;     /* s is socket id */
> if (hashmap__find(mask, (void *)key, NULL))
>       *skip = true;
> else
>       ret = hashmap__add(mask, (void *)key, (void *)1);
> 
> If we use 'unsigned long' to replace 'size_t', it reports the build error for 
> 32 bits:
> 
> stat.c:320:23: warning: passing argument 1 of ‘hashmap__new’ from
> incompatible pointer type [-Wincompatible-pointer-types]
>    mask = hashmap__new(pkg_id_hash, pkg_id_equal, NULL);
>                        ^~~~~~~~~~~
> In file included from stat.c:16:
> hashmap.h:75:17: note: expected ‘hashmap_hash_fn’ {aka ‘unsigned int
> (*)(const void *, void *)’} but argument is of type ‘long unsigned int
> (*)(const void *, void *)’
> 
> If we use "unsigned int", it's not good for 64 bits. So I still use 'size_t' 
> in this patch.
> 
> Any comments for this idea (using conditional compilation)?

isn't it simpler to allocate the key then? like below
(just compile tested)

jirka


---
diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
index 5aba8fa92386..195fda142c98 100644
--- a/tools/perf/util/stat.c
+++ b/tools/perf/util/stat.c
@@ -276,19 +276,31 @@ void evlist__save_aggr_prev_raw_counts(struct evlist 
*evlist)
 
 static void zero_per_pkg(struct evsel *counter)
 {
-       if (counter->per_pkg_mask)
+       struct hashmap_entry *cur;
+       size_t bkt;
+
+       if (counter->per_pkg_mask) {
+               hashmap__for_each_entry(counter->per_pkg_mask, cur, bkt)
+                       free((char *)cur->key);
+
                hashmap__clear(counter->per_pkg_mask);
+       }
 }
 
-static size_t pkg_id_hash(const void *key, void *ctx __maybe_unused)
+static size_t pkg_id_hash(const void *__key, void *ctx __maybe_unused)
 {
-       return (size_t)key & 0xffff;
+       uint64_t *key = (uint64_t*) __key;
+
+       return *key & 0xffffffff;
 }
 
-static bool pkg_id_equal(const void *key1, const void *key2,
+static bool pkg_id_equal(const void *__key1, const void *__key2,
                         void *ctx __maybe_unused)
 {
-       return (size_t)key1 == (size_t)key2;
+       uint64_t *key1 = (uint64_t*) __key1;
+       uint64_t *key2 = (uint64_t*) __key2;
+
+       return *key1 == *key2;
 }
 
 static int check_per_pkg(struct evsel *counter,
@@ -297,7 +309,7 @@ static int check_per_pkg(struct evsel *counter,
        struct hashmap *mask = counter->per_pkg_mask;
        struct perf_cpu_map *cpus = evsel__cpus(counter);
        int s, d, ret = 0;
-       size_t key;
+       uint64_t *key;
 
        *skip = false;
 
@@ -338,7 +350,11 @@ static int check_per_pkg(struct evsel *counter,
        if (d < 0)
                return -1;
 
-       key = (size_t)d << 16 | s;
+       key = malloc(sizeof(*key));
+       if (!key)
+               return -ENOMEM;
+
+       *key = (size_t)d << 32 | s;
        if (hashmap__find(mask, (void *)key, NULL))
                *skip = true;
        else