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x86/aperfmperf: Untangle Intel and AMD frequency invariance init

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AMD boot CPU initialization happens late via ACPI/CPPC which prevents the
Intel parts from being marked __init.

Split out the common code and provide a dedicated interface for the AMD
initialization and mark the Intel specific code and data __init.

The remaining text size is almost cut in half:

  text:		2614	->	1350
  init.text:	   0	->	 786

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220415161206.592465719@linutronix.de
This commit is contained in:
Thomas Gleixner
2022-04-15 21:19:54 +02:00
parent 138a7f9c6b
commit 0dfaf3f6ec
4 changed files with 52 additions and 57 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
arch/x86/kernel/acpi/cppc.c
View File

@ -50,20 +50,17 @@ int cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val)
return err;
}
bool amd_set_max_freq_ratio(u64 *ratio)
static void amd_set_max_freq_ratio(void)
{
struct cppc_perf_caps perf_caps;
u64 highest_perf, nominal_perf;
u64 perf_ratio;
int rc;
if (!ratio)
return false;
rc = cppc_get_perf_caps(0, &perf_caps);
if (rc) {
pr_debug("Could not retrieve perf counters (%d)\n", rc);
return false;
return;
}
highest_perf = amd_get_highest_perf();
@ -71,7 +68,7 @@ bool amd_set_max_freq_ratio(u64 *ratio)
if (!highest_perf || !nominal_perf) {
pr_debug("Could not retrieve highest or nominal performance\n");
return false;
return;
}
perf_ratio = div_u64(highest_perf * SCHED_CAPACITY_SCALE, nominal_perf);
@ -79,26 +76,27 @@ bool amd_set_max_freq_ratio(u64 *ratio)
perf_ratio = (perf_ratio + SCHED_CAPACITY_SCALE) >> 1;
if (!perf_ratio) {
pr_debug("Non-zero highest/nominal perf values led to a 0 ratio\n");
return false;
return;
}
*ratio = perf_ratio;
arch_set_max_freq_ratio(false);
return true;
freq_invariance_set_perf_ratio(perf_ratio, false);
}
static DEFINE_MUTEX(freq_invariance_lock);
void init_freq_invariance_cppc(void)
{
static bool secondary;
static bool init_done;
if (!cpu_feature_enabled(X86_FEATURE_APERFMPERF))
return;
if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
return;
mutex_lock(&freq_invariance_lock);
if (!secondary)
bp_init_freq_invariance(true);
secondary = true;
if (!init_done)
amd_set_max_freq_ratio();
init_done = true;
mutex_unlock(&freq_invariance_lock);
}