linux-kernel - [PATCH PATCH v2 2/9] cpufreq: intel_pstate: Use topology_cpu

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Date: Thu, 27 Jun 2024 13:44:12 -0700
From: Pawan Gupta <pawan.kumar.gupta@...ux.intel.com>
To: Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>,
	Borislav Petkov <bp@...en8.de>,
	Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org
Cc: daniel.sneddon@...ux.intel.com, tony.luck@...el.com,
	linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org,
	linux-perf-users@...r.kernel.org,
	Josh Poimboeuf <jpoimboe@...nel.org>,
	Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
	"Rafael J. Wysocki" <rafael@...nel.org>,
	Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>,
	"Liang, Kan" <kan.liang@...ux.intel.com>,
	Andrew Cooper <andrew.cooper3@...rix.com>,
	Brice Goglin <brice.goglin@...il.com>,
	Mario Limonciello <mario.limonciello@....com>,
	Perry Yuan <Perry.Yuan@....com>,
	Dapeng Mi <dapeng1.mi@...ux.intel.com>
Subject: [PATCH PATCH v2 2/9] cpufreq: intel_pstate: Use topology_cpu_type()

Intel pstate driver uses hybrid_get_type() to get the cpu-type of a given
CPU. It uses smp_call_function_single() which is sub-optimal. Avoid it by
using topology_hw_cpu_type(cpu) that returns the cached cpu-type.

Suggested-by: Dave Hansen <dave.hansen@...ux.intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@...ux.intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>
---
 drivers/cpufreq/intel_pstate.c | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 15de5e3d96fd..0a1e832c7536 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -1956,24 +1956,16 @@ static int knl_get_turbo_pstate(int cpu)
 	return ret;
 }
 
-static void hybrid_get_type(void *data)
-{
-	u8 *cpu_type = data;
-
-	*cpu_type = get_this_hybrid_cpu_type();
-}
-
 static int hwp_get_cpu_scaling(int cpu)
 {
-	u8 cpu_type = 0;
+	u8 cpu_type = topology_hw_cpu_type(cpu);
 
-	smp_call_function_single(cpu, hybrid_get_type, &cpu_type, 1);
 	/* P-cores have a smaller perf level-to-freqency scaling factor. */
-	if (cpu_type == 0x40)
+	if (cpu_type == X86_HW_CPU_TYPE_INTEL_CORE)
 		return hybrid_scaling_factor;
 
 	/* Use default core scaling for E-cores */
-	if (cpu_type == 0x20)
+	if (cpu_type == X86_HW_CPU_TYPE_INTEL_ATOM)
 		return core_get_scaling();
 
 	/*

-- 
2.34.1