[tip: perf/core] perf/x86/intel: Rename x86_pmu.pebs to x86_pmu.ds_pebs

["tip-bot2 for Dapeng Mi" <tip-bot2@linutronix.de>]

The following commit has been merged into the perf/core branch of tip:

Commit-ID:     acb727e0956a2424f22e5ab8c1ff9a39d1acb150
Gitweb:        https://git.kernel.org/tip/acb727e0956a2424f22e5ab8c1ff9a39d1acb150
Author:        Dapeng Mi <dapeng1.mi@linux.intel.com>
AuthorDate:    Tue, 15 Apr 2025 11:44:11 
Committer:     Ingo Molnar <mingo@kernel.org>
CommitterDate: Thu, 17 Apr 2025 14:21:24 +02:00

perf/x86/intel: Rename x86_pmu.pebs to x86_pmu.ds_pebs

Since architectural PEBS would be introduced in subsequent patches,
rename x86_pmu.pebs to x86_pmu.ds_pebs for distinguishing with the
upcoming architectural PEBS.

Besides restrict reserve_ds_buffers() helper to work only for the
legacy DS based PEBS and avoid it to corrupt the pebs_active flag and
release PEBS buffer incorrectly for arch-PEBS since the later patch
would reuse these flags and alloc/release_pebs_buffer() helpers for
arch-PEBS.

Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20250415114428.341182-6-dapeng1.mi@linux.intel.com
---
 arch/x86/events/intel/core.c |  6 +++---
 arch/x86/events/intel/ds.c   | 32 ++++++++++++++++++--------------
 arch/x86/events/perf_event.h |  2 +-
 3 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 16049ba..7bbc7a7 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -4584,7 +4584,7 @@ static struct perf_guest_switch_msr *intel_guest_get_msrs(int *nr, void *data)
 		.guest = intel_ctrl & ~cpuc->intel_ctrl_host_mask & ~pebs_mask,
 	};
 
-	if (!x86_pmu.pebs)
+	if (!x86_pmu.ds_pebs)
 		return arr;
 
 	/*
@@ -5764,7 +5764,7 @@ static __init void intel_clovertown_quirk(void)
 	 * these chips.
 	 */
 	pr_warn("PEBS disabled due to CPU errata\n");
-	x86_pmu.pebs = 0;
+	x86_pmu.ds_pebs = 0;
 	x86_pmu.pebs_constraints = NULL;
 }
 
@@ -6252,7 +6252,7 @@ tsx_is_visible(struct kobject *kobj, struct attribute *attr, int i)
 static umode_t
 pebs_is_visible(struct kobject *kobj, struct attribute *attr, int i)
 {
-	return x86_pmu.pebs ? attr->mode : 0;
+	return x86_pmu.ds_pebs ? attr->mode : 0;
 }
 
 static umode_t
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index d894cf3..1d6b3fa 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -624,7 +624,7 @@ static int alloc_pebs_buffer(int cpu)
 	int max, node = cpu_to_node(cpu);
 	void *buffer, *insn_buff, *cea;
 
-	if (!x86_pmu.pebs)
+	if (!x86_pmu.ds_pebs)
 		return 0;
 
 	buffer = dsalloc_pages(bsiz, GFP_KERNEL, cpu);
@@ -659,7 +659,7 @@ static void release_pebs_buffer(int cpu)
 	struct cpu_hw_events *hwev = per_cpu_ptr(&cpu_hw_events, cpu);
 	void *cea;
 
-	if (!x86_pmu.pebs)
+	if (!x86_pmu.ds_pebs)
 		return;
 
 	kfree(per_cpu(insn_buffer, cpu));
@@ -734,7 +734,7 @@ void release_ds_buffers(void)
 {
 	int cpu;
 
-	if (!x86_pmu.bts && !x86_pmu.pebs)
+	if (!x86_pmu.bts && !x86_pmu.ds_pebs)
 		return;
 
 	for_each_possible_cpu(cpu)
@@ -750,7 +750,8 @@ void release_ds_buffers(void)
 	}
 
 	for_each_possible_cpu(cpu) {
-		release_pebs_buffer(cpu);
+		if (x86_pmu.ds_pebs)
+			release_pebs_buffer(cpu);
 		release_bts_buffer(cpu);
 	}
 }
@@ -761,15 +762,17 @@ void reserve_ds_buffers(void)
 	int cpu;
 
 	x86_pmu.bts_active = 0;
-	x86_pmu.pebs_active = 0;
 
-	if (!x86_pmu.bts && !x86_pmu.pebs)
+	if (x86_pmu.ds_pebs)
+		x86_pmu.pebs_active = 0;
+
+	if (!x86_pmu.bts && !x86_pmu.ds_pebs)
 		return;
 
 	if (!x86_pmu.bts)
 		bts_err = 1;
 
-	if (!x86_pmu.pebs)
+	if (!x86_pmu.ds_pebs)
 		pebs_err = 1;
 
 	for_each_possible_cpu(cpu) {
@@ -781,7 +784,8 @@ void reserve_ds_buffers(void)
 		if (!bts_err && alloc_bts_buffer(cpu))
 			bts_err = 1;
 
-		if (!pebs_err && alloc_pebs_buffer(cpu))
+		if (x86_pmu.ds_pebs && !pebs_err &&
+		    alloc_pebs_buffer(cpu))
 			pebs_err = 1;
 
 		if (bts_err && pebs_err)
@@ -793,7 +797,7 @@ void reserve_ds_buffers(void)
 			release_bts_buffer(cpu);
 	}
 
-	if (pebs_err) {
+	if (x86_pmu.ds_pebs && pebs_err) {
 		for_each_possible_cpu(cpu)
 			release_pebs_buffer(cpu);
 	}
@@ -805,7 +809,7 @@ void reserve_ds_buffers(void)
 		if (x86_pmu.bts && !bts_err)
 			x86_pmu.bts_active = 1;
 
-		if (x86_pmu.pebs && !pebs_err)
+		if (x86_pmu.ds_pebs && !pebs_err)
 			x86_pmu.pebs_active = 1;
 
 		for_each_possible_cpu(cpu) {
@@ -2662,12 +2666,12 @@ void __init intel_pebs_init(void)
 	if (!boot_cpu_has(X86_FEATURE_DTES64))
 		return;
 
-	x86_pmu.pebs = boot_cpu_has(X86_FEATURE_PEBS);
+	x86_pmu.ds_pebs = boot_cpu_has(X86_FEATURE_PEBS);
 	x86_pmu.pebs_buffer_size = PEBS_BUFFER_SIZE;
 	if (x86_pmu.version <= 4)
 		x86_pmu.pebs_no_isolation = 1;
 
-	if (x86_pmu.pebs) {
+	if (x86_pmu.ds_pebs) {
 		char pebs_type = x86_pmu.intel_cap.pebs_trap ?  '+' : '-';
 		char *pebs_qual = "";
 		int format = x86_pmu.intel_cap.pebs_format;
@@ -2759,7 +2763,7 @@ void __init intel_pebs_init(void)
 
 		default:
 			pr_cont("no PEBS fmt%d%c, ", format, pebs_type);
-			x86_pmu.pebs = 0;
+			x86_pmu.ds_pebs = 0;
 		}
 	}
 }
@@ -2768,7 +2772,7 @@ void perf_restore_debug_store(void)
 {
 	struct debug_store *ds = __this_cpu_read(cpu_hw_events.ds);
 
-	if (!x86_pmu.bts && !x86_pmu.pebs)
+	if (!x86_pmu.bts && !x86_pmu.ds_pebs)
 		return;
 
 	wrmsrl(MSR_IA32_DS_AREA, (unsigned long)ds);
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index ac6743e..2ef407d 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -898,7 +898,7 @@ struct x86_pmu {
 	 */
 	unsigned int	bts			:1,
 			bts_active		:1,
-			pebs			:1,
+			ds_pebs			:1,
 			pebs_active		:1,
 			pebs_broken		:1,
 			pebs_prec_dist		:1,