[RFC PATCH v2 04/34] x86/msr: Convert rdpmcq() into a function

Xin Li (Intel)
2025-04-22T08:23:52Z

Signed-off-by: Xin Li (Intel) <xin@zytor.com>
---
arch/x86/events/amd/uncore.c | 2 +-
arch/x86/events/core.c | 2 +-
arch/x86/events/intel/core.c | 4 ++--
arch/x86/events/intel/ds.c | 2 +-
arch/x86/include/asm/msr.h | 5 ++++-
arch/x86/include/asm/paravirt.h | 4 +---
arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 12 ++++++------
7 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c
index b9933ab3116c..f2601c662783 100644
--- a/arch/x86/events/amd/uncore.c
+++ b/arch/x86/events/amd/uncore.c
@@ -152,7 +152,7 @@ static void amd_uncore_read(struct perf_event *event)
if (hwc->event_base_rdpmc < 0)
rdmsrq(hwc->event_base, new);
else
- rdpmcq(hwc->event_base_rdpmc, new);
+ new = rdpmcq(hwc->event_base_rdpmc);

local64_set(&hwc->prev_count, new);
delta = (new << COUNTER_SHIFT) - (prev << COUNTER_SHIFT);
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 3da1f0b3446c..0a3939b9965e 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -139,7 +139,7 @@ u64 x86_perf_event_update(struct perf_event *event)
*/
prev_raw_count = local64_read(&hwc->prev_count);
do {
- rdpmcq(hwc->event_base_rdpmc, new_raw_count);
+ new_raw_count = rdpmcq(hwc->event_base_rdpmc);
} while (!local64_try_cmpxchg(&hwc->prev_count,
&prev_raw_count, new_raw_count));

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index ba623e6cae1b..4370d0d86013 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -2739,12 +2739,12 @@ static u64 intel_update_topdown_event(struct perf_event *event, int metric_end,

if (!val) {
/* read Fixed counter 3 */
- rdpmcq((3 | INTEL_PMC_FIXED_RDPMC_BASE), slots);
+ slots = rdpmcq(3 | INTEL_PMC_FIXED_RDPMC_BASE);
if (!slots)
return 0;

/* read PERF_METRICS */
- rdpmcq(INTEL_PMC_FIXED_RDPMC_METRICS, metrics);
+ metrics = rdpmcq(INTEL_PMC_FIXED_RDPMC_METRICS);
} else {
slots = val[0];
metrics = val[1];
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index 4074567219de..845439fd9c03 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -2279,7 +2279,7 @@ intel_pmu_save_and_restart_reload(struct perf_event *event, int count)
WARN_ON(this_cpu_read(cpu_hw_events.enabled));

prev_raw_count = local64_read(&hwc->prev_count);
- rdpmcq(hwc->event_base_rdpmc, new_raw_count);
+ new_raw_count = rdpmcq(hwc->event_base_rdpmc);
local64_set(&hwc->prev_count, new_raw_count);

/*
diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index ed32637b1df6..01dc8e61ef97 100644
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -234,7 +234,10 @@ static inline int rdmsrq_safe(u32 msr, u64 *p)
return err;
}

-#define rdpmcq(counter, val) ((val) = native_read_pmc(counter))
+static __always_inline u64 rdpmcq(int counter)
+{
+ return native_read_pmc(counter);
+}

#endif /* !CONFIG_PARAVIRT_XXL */

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 63ca099f8368..590824916394 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -239,13 +239,11 @@ static inline int rdmsrq_safe(unsigned msr, u64 *p)
return err;
}

-static inline u64 paravirt_read_pmc(int counter)
+static __always_inline u64 rdpmcq(int counter)
{
return PVOP_CALL1(u64, cpu.read_pmc, counter);
}

-#define rdpmcq(counter, val) ((val) = paravirt_read_pmc(counter))
-
static inline void paravirt_alloc_ldt(struct desc_struct *ldt, unsigned entries)
{
PVOP_VCALL2(cpu.alloc_ldt, ldt, entries);
diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index a5e21f44b0ca..276ffab194f6 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -1019,8 +1019,8 @@ static int measure_residency_fn(struct perf_event_attr *miss_attr,
* used in L1 cache, second to capture accurate value that does not
* include cache misses incurred because of instruction loads.
*/
- rdpmcq(hit_pmcnum, hits_before);
- rdpmcq(miss_pmcnum, miss_before);
+ hits_before = rdpmcq(hit_pmcnum);
+ miss_before = rdpmcq(miss_pmcnum);
/*
* From SDM: Performing back-to-back fast reads are not guaranteed
* to be monotonic.
@@ -1028,8 +1028,8 @@ static int measure_residency_fn(struct perf_event_attr *miss_attr,
* before proceeding.
*/
rmb();
- rdpmcq(hit_pmcnum, hits_before);
- rdpmcq(miss_pmcnum, miss_before);
+ hits_before = rdpmcq(hit_pmcnum);
+ miss_before = rdpmcq(miss_pmcnum);
/*
* Use LFENCE to ensure all previous instructions are retired
* before proceeding.
@@ -1051,8 +1051,8 @@ static int measure_residency_fn(struct perf_event_attr *miss_attr,
* before proceeding.
*/
rmb();
- rdpmcq(hit_pmcnum, hits_after);
- rdpmcq(miss_pmcnum, miss_after);
+ hits_after = rdpmcq(hit_pmcnum);
+ miss_after = rdpmcq(miss_pmcnum);
/*
* Use LFENCE to ensure all previous instructions are retired
* before proceeding.
--
2.49.0