perf tools: Read the cache line size lazily

It is not read as commonly as 'page_size', so it makes sense to read it
lazily, caching its value when it is first read.

Less files open unconditionally at startup.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-35xhrq91u94uc1djtclek1ie@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index e65903a695a6..4058ade352a5 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -2582,7 +2582,7 @@ int sort_dimension__add(struct perf_hpp_list *list, const char *tok,
                 if (sort__mode != SORT_MODE__MEMORY)
                         return -EINVAL;
 
-                if (sd->entry == &sort_mem_dcacheline && cacheline_size == 0)
+                if (sd->entry == &sort_mem_dcacheline && cacheline_size() == 0)
                         return -EINVAL;
 
                 if (sd->entry == &sort_mem_daddr_sym)
@@ -2628,7 +2628,7 @@ static int setup_sort_list(struct perf_hpp_list *list, char *str,
                 if (*tok) {
                         ret = sort_dimension__add(list, tok, evlist, level);
                         if (ret == -EINVAL) {
-                                if (!cacheline_size && !strncasecmp(tok, "dcacheline", strlen(tok)))
+                                if (!cacheline_size() && !strncasecmp(tok, "dcacheline", strlen(tok)))
                                         pr_err("The \"dcacheline\" --sort key needs to know the cacheline size and it couldn't be determined on this system");
                                 else
                                         pr_err("Invalid --sort key: `%s'", tok);