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Major refactoring of the Intel match tables.

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There were a lot of instances where there was additional code
written to detect certain features from the brand string
(e.g., does it have "Core (TM)"? if it has, does it have "i3"?).
It makes sense to only write code for detecting these features
in isolation, preventing the exponential blowup of possible
intel_code_t values (e.g. previously there were enum values
for CORE_{,IVY,HASWELL,BROADWELL,SKYLAKE}{,M}{3,5,7} - almost
20 separate enums items; these can now be expressed with the
respective bits (CORE_, _I_, _M_, _3, _5 and _7).

The change in matchtables is the addition of an extra field
after brand_code: it is called model_bits. The bits for each
vendor is defined in the beginning of recog_<<vendor>>.c

This is the first part of the overhaul, which handles the bits
detection and proper matchtables for Intel. Refactoring of
AMD detection code coming next...
This commit is contained in:
Veselin Georgiev 2017-03-20 01:01:22 +02:00
commit 8179882abb
6 changed files with 573 additions and 539 deletions
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45
libcpuid/libcpuid_util.c
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@ -74,8 +74,20 @@ void debugf(int verboselevel, const char* format, ...)
_warn_fun(buff);
}
static int popcount64(uint64_t mask)
{
int num_set_bits = 0;
while (mask) {
mask &= mask - 1;
num_set_bits++;
}
return num_set_bits;
}
static int score(const struct match_entry_t* entry, const struct cpu_id_t* data,
int brand_code, int model_code)
int brand_code, uint64_t bits, int model_code)
{
int res = 0;
if (entry->family == data->family ) res += 2;
@ -86,24 +98,27 @@ static int score(const struct match_entry_t* entry, const struct cpu_id_t* data,
if (entry->ncores == data->num_cores ) res += 2;
if (entry->l2cache == data->l2_cache ) res += 1;
if (entry->l3cache == data->l3_cache ) res += 1;
if (entry->brand_code == brand_code ) res += 2;
if (entry->model_code == model_code ) res += 2;
if (entry->brand_code == brand_code ) res += 2;
if (entry->model_code == model_code ) res += 2;
res += popcount64(entry->model_bits & bits) * 2;
return res;
}
int match_cpu_codename(const struct match_entry_t* matchtable, int count,
struct cpu_id_t* data, int brand_code, int model_code)
struct cpu_id_t* data, int brand_code, uint64_t bits,
int model_code)
{
int bestscore = -1;
int bestindex = 0;
int i, t;
debugf(3, "Matching cpu f:%d, m:%d, s:%d, xf:%d, xm:%d, ncore:%d, l2:%d, bcode:%d, code:%d\n",
debugf(3, "Matching cpu f:%d, m:%d, s:%d, xf:%d, xm:%d, ncore:%d, l2:%d, bcode:%d, bits:%llu, code:%d\n",
data->family, data->model, data->stepping, data->ext_family,
data->ext_model, data->num_cores, data->l2_cache, brand_code, model_code);
data->ext_model, data->num_cores, data->l2_cache, brand_code, (unsigned long long) bits, model_code);
for (i = 0; i < count; i++) {
t = score(&matchtable[i], data, brand_code, model_code);
t = score(&matchtable[i], data, brand_code, bits, model_code);
debugf(3, "Entry %d, `%s', score %d\n", i, matchtable[i].name, t);
if (t > bestscore) {
debugf(2, "Entry `%s' selected - best score so far (%d)\n", matchtable[i].name, t);
@ -185,3 +200,19 @@ struct cpu_id_t* get_cached_cpuid(void)
initialized = 1;
return &id;
}
int match_all(uint64_t bits, uint64_t mask)
{
return (bits & mask) == mask;
}
void debug_print_lbits(int debuglevel, uint64_t mask)
{
int i, first = 0;
for (i = 0; i < 64; i++) if (mask & (((uint64_t) 1) << i)) {
if (first) first = 0;
else debugf(2, " + ");
debugf(2, "LBIT(%d)", i);
}
debugf(2, "\n");
}