+ /*
+ * Full CPUID format is required to identify a platform.
+ * Error out if the cpuid string is incomplete.
+ */
+ if (full_mapcpuid && !full_cpuid) {
+ pr_info("Invalid CPUID %s. Full CPUID is required, "
+ "vendor-family-model-stepping\n", cpuid);
+ return 1;
+ }
+
+ if (regcomp(&re, mapcpuid, REG_EXTENDED) != 0) {
+ /* Warn unable to generate match particular string. */
+ pr_info("Invalid regular expression %s\n", mapcpuid);
+ return 1;
+ }
+
+ match = !regexec(&re, cpuid, 1, pmatch, 0);
+ regfree(&re);
+ if (match) {
+ size_t match_len = (pmatch[0].rm_eo - pmatch[0].rm_so);
+ size_t cpuid_len;
+
+ /* If the full CPUID format isn't required,
+ * ignoring the stepping.
+ */
+ if (!full_mapcpuid && full_cpuid)
+ cpuid_len = strrchr(cpuid, '-') - cpuid;
+ else
+ cpuid_len = strlen(cpuid);
+
+
+ /* Verify the entire string matched. */
+ if (match_len == cpuid_len)
+ return 0;
why is this necessary?
It's from previous common code. As my understanding, it just double check
the matched strings. There is no harmful. So I keep it.
right.. did you consider using the wildcard in the map file
so it'd cover the stepping, having entries like:
GenuineIntel-6-1F-*,v2,nehalemep,core
I haven't thought this one through, but seems we could bypass
those '-stepping' checks.. but probably other changes would be
necessary for the wildcard
If using wildcard, the full cpuid format is required for all platforms.
The script which using environment string "PERF_CPUID" will definitely
be broken on all platforms.
This patch (non-wildcard) only breaks the script on Skylake server and
Cascadelake server.
I think that's the only drawback of using wildcard.
Thanks,
Kan
