mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: K Prateek Nayak <kprateek.nayak@amd.com>
To: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Sean Christopherson <seanjc@google.com>,
	Paolo Bonzini <pbonzini@redhat.com>, <x86@kernel.org>
Cc: Naveen rao <naveen.rao@amd.com>,
	Sairaj Kodilkar <sarunkod@amd.com>,
	"H. Peter Anvin" <hpa@zytor.com>,
	"Peter Zijlstra (Intel)" <peterz@infradead.org>,
	"Xin Li (Intel)" <xin@zytor.com>,
	Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
	<linux-kernel@vger.kernel.org>, <kvm@vger.kernel.org>,
	Mario Limonciello <mario.limonciello@amd.com>,
	"Gautham R. Shenoy" <gautham.shenoy@amd.com>,
	Babu Moger <babu.moger@amd.com>,
	Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
	K Prateek Nayak <kprateek.nayak@amd.com>
Subject: [PATCH v3 4/4] x86/cpu/topology: Check for X86_FEATURE_XTOPOLOGY instead of passing has_topoext
Date: Mon, 18 Aug 2025 06:04:35 +0000	[thread overview]
Message-ID: <20250818060435.2452-5-kprateek.nayak@amd.com> (raw)
In-Reply-To: <20250818060435.2452-1-kprateek.nayak@amd.com>

cpu_parse_topology_ext() sets X86_FEATURE_XTOPOLOGY before returning
true if any of the XTOPOLOGY leaf could be parsed successfully.

Instead of storing and passing around this return value using
"has_topoext" in parse_topology_amd(), check for X86_FEATURE_XTOPOLOGY
instead in parse_8000_001e() to simplify the flow.

No functional changes intended.

Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
---
Changelog v2..v3:

o Use cpu_feature_enabled() when checking for X86_FEATURE_XTOPOLOGY.
---
 arch/x86/kernel/cpu/topology_amd.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/cpu/topology_amd.c b/arch/x86/kernel/cpu/topology_amd.c
index 3d01675d94f5..138a09528083 100644
--- a/arch/x86/kernel/cpu/topology_amd.c
+++ b/arch/x86/kernel/cpu/topology_amd.c
@@ -59,7 +59,7 @@ static void store_node(struct topo_scan *tscan, u16 nr_nodes, u16 node_id)
 	tscan->amd_node_id = node_id;
 }
 
-static bool parse_8000_001e(struct topo_scan *tscan, bool has_topoext)
+static bool parse_8000_001e(struct topo_scan *tscan)
 {
 	struct {
 		// eax
@@ -81,7 +81,7 @@ static bool parse_8000_001e(struct topo_scan *tscan, bool has_topoext)
 
 	cpuid_leaf(0x8000001e, &leaf);
 
-	if (!has_topoext) {
+	if (!cpu_feature_enabled(X86_FEATURE_XTOPOLOGY)) {
 		/*
 		 * Prefer initial_apicid parsed from XTOPOLOGY leaf
 		 * 0x8000026 or 0xb if available. Otherwise prefer the
@@ -179,6 +179,9 @@ static void topoext_fixup(struct topo_scan *tscan)
 
 static void parse_topology_amd(struct topo_scan *tscan)
 {
+	if (cpu_feature_enabled(X86_FEATURE_AMD_HTR_CORES))
+		tscan->c->topo.cpu_type = cpuid_ebx(0x80000026);
+
 	/*
 	 * Try to get SMT, CORE, TILE, and DIE shifts from extended
 	 * CPUID leaf 0x8000_0026 on supported processors first. If
@@ -186,16 +189,11 @@ static void parse_topology_amd(struct topo_scan *tscan)
 	 * get SMT and CORE shift from leaf 0xb first, then try to
 	 * get the CORE shift from leaf 0x8000_0008.
 	 */
-	bool has_topoext = cpu_parse_topology_ext(tscan);
-
-	if (cpu_feature_enabled(X86_FEATURE_AMD_HTR_CORES))
-		tscan->c->topo.cpu_type = cpuid_ebx(0x80000026);
-
-	if (!has_topoext && !parse_8000_0008(tscan))
+	if (!cpu_parse_topology_ext(tscan) && !parse_8000_0008(tscan))
 		return;
 
 	/* Prefer leaf 0x8000001e if available */
-	if (parse_8000_001e(tscan, has_topoext))
+	if (parse_8000_001e(tscan))
 		return;
 
 	/* Try the NODEID MSR */
-- 
2.34.1


  parent reply	other threads:[~2025-08-18  6:06 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-08-18  6:04 [PATCH v3 0/4] x86/cpu/topology: Work around the nuances of virtualization on AMD/Hygon K Prateek Nayak
2025-08-18  6:04 ` [PATCH v3 1/4] x86/msr-index: Define AMD64_CPUID_FN_EXT MSR K Prateek Nayak
2025-08-18  6:04 ` [PATCH v3 2/4] x86/cpu/topology: Use initial APICID from XTOPOEXT on AMD/HYGON K Prateek Nayak
2025-08-18  6:04 ` [PATCH v3 3/4] x86/cpu/topology: Always try cpu_parse_topology_ext() on AMD/Hygon K Prateek Nayak
2025-08-18  6:04 ` K Prateek Nayak [this message]
2025-08-24 13:38   ` [PATCH v3 4/4] x86/cpu/topology: Check for X86_FEATURE_XTOPOLOGY instead of passing has_topoext Thomas Gleixner
2025-08-24 14:55     ` Thomas Gleixner
2025-08-25  4:05       ` K Prateek Nayak
2025-08-19 11:34 ` [PATCH v3 0/4] x86/cpu/topology: Work around the nuances of virtualization on AMD/Hygon Borislav Petkov
2025-08-19 14:28   ` K Prateek Nayak
2025-08-19 21:24     ` Borislav Petkov
2025-08-20  8:11   ` Naveen N Rao
2025-08-20  8:59     ` Borislav Petkov
2025-08-20  9:12       ` K Prateek Nayak
2025-08-20  9:28         ` Borislav Petkov
2025-08-20  9:59         ` Gautham R. Shenoy

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20250818060435.2452-5-kprateek.nayak@amd.com \
    --to=kprateek.nayak@amd.com \
    --cc=babu.moger@amd.com \
    --cc=bp@alien8.de \
    --cc=dave.hansen@linux.intel.com \
    --cc=gautham.shenoy@amd.com \
    --cc=hpa@zytor.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mario.limonciello@amd.com \
    --cc=mingo@redhat.com \
    --cc=naveen.rao@amd.com \
    --cc=pawan.kumar.gupta@linux.intel.com \
    --cc=pbonzini@redhat.com \
    --cc=peterz@infradead.org \
    --cc=sarunkod@amd.com \
    --cc=seanjc@google.com \
    --cc=suravee.suthikulpanit@amd.com \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    --cc=xin@zytor.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®