linux-kernel - [PATCH v2 3/5] x86/mce: Introduce mce_handle_storm() to deal with begin/end of storms

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Date:   Mon, 27 Jun 2022 10:36:03 -0700
From:   Tony Luck <tony.luck@...el.com>
To:     Borislav Petkov <bp@...en8.de>
Cc:     Smita.KoralahalliChannabasappa@....com,
        dave.hansen@...ux.intel.com, hpa@...or.com,
        linux-edac@...r.kernel.org, linux-kernel@...r.kernel.org,
        x86@...nel.org, yazen.ghannam@....com, patches@...ts.linux.dev,
        Tony Luck <tony.luck@...el.com>
Subject: [PATCH v2 3/5] x86/mce: Introduce mce_handle_storm() to deal with begin/end of storms

From: Smita Koralahalli <Smita.KoralahalliChannabasappa@....com>

Intel and AMD need to take different actions when a storm begins or
ends. Prepare for the storm code moving from intel.c into core.c by
adding a function that checks CPU vendor to pick the right action.

No functional changes.

[Tony: Changed from function pointer to regular function]

Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@....com>
Signed-off-by: Tony Luck <tony.luck@...el.com>
---
 arch/x86/kernel/cpu/mce/core.c     |  9 +++++++++
 arch/x86/kernel/cpu/mce/intel.c    | 12 ++++++++++--
 arch/x86/kernel/cpu/mce/internal.h |  3 +++
 3 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 776d4724b1e0..f4d2a7ba29f7 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1985,6 +1985,15 @@ static void mce_zhaoxin_feature_clear(struct cpuinfo_x86 *c)
 	intel_clear_lmce();
 }
 
+void mce_handle_storm(int bank, bool on)
+{
+	switch (boot_cpu_data.x86_vendor) {
+	case X86_VENDOR_INTEL:
+		mce_intel_handle_storm(bank, on);
+		break;
+	}
+}
+
 static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
 {
 	switch (c->x86_vendor) {
diff --git a/arch/x86/kernel/cpu/mce/intel.c b/arch/x86/kernel/cpu/mce/intel.c
index 4106877de028..4238b73c2143 100644
--- a/arch/x86/kernel/cpu/mce/intel.c
+++ b/arch/x86/kernel/cpu/mce/intel.c
@@ -152,6 +152,14 @@ static void cmci_set_threshold(int bank, int thresh)
 	raw_spin_unlock_irqrestore(&cmci_discover_lock, flags);
 }
 
+void mce_intel_handle_storm(int bank, bool on)
+{
+	if (on)
+		cmci_set_threshold(bank, cmci_threshold[bank]);
+	else
+		cmci_set_threshold(bank, CMCI_STORM_THRESHOLD);
+}
+
 static void cmci_storm_begin(int bank)
 {
 	__set_bit(bank, this_cpu_ptr(mce_poll_banks));
@@ -211,13 +219,13 @@ void track_cmci_storm(int bank, u64 status)
 		if (history & GENMASK_ULL(STORM_END_POLL_THRESHOLD - 1, 0))
 			return;
 		pr_notice("CPU%d BANK%d CMCI storm subsided\n", smp_processor_id(), bank);
-		cmci_set_threshold(bank, cmci_threshold[bank]);
+		mce_handle_storm(bank, true);
 		cmci_storm_end(bank);
 	} else {
 		if (hweight64(history) < STORM_BEGIN_THRESHOLD)
 			return;
 		pr_notice("CPU%d BANK%d CMCI storm detected\n", smp_processor_id(), bank);
-		cmci_set_threshold(bank, CMCI_STORM_THRESHOLD);
+		mce_handle_storm(bank, false);
 		cmci_storm_begin(bank);
 	}
 }
diff --git a/arch/x86/kernel/cpu/mce/internal.h b/arch/x86/kernel/cpu/mce/internal.h
index ab451526f6df..78467f6cdd04 100644
--- a/arch/x86/kernel/cpu/mce/internal.h
+++ b/arch/x86/kernel/cpu/mce/internal.h
@@ -43,12 +43,14 @@ extern mce_banks_t mce_banks_ce_disabled;
 void track_cmci_storm(int bank, u64 status);
 
 #ifdef CONFIG_X86_MCE_INTEL
+void mce_intel_handle_storm(int bank, bool on);
 void cmci_disable_bank(int bank);
 void intel_init_cmci(void);
 void intel_init_lmce(void);
 void intel_clear_lmce(void);
 bool intel_filter_mce(struct mce *m);
 #else
+static inline void mce_intel_handle_storm(int bank, bool on) { }
 static inline void cmci_disable_bank(int bank) { }
 static inline void intel_init_cmci(void) { }
 static inline void intel_init_lmce(void) { }
@@ -57,6 +59,7 @@ static inline bool intel_filter_mce(struct mce *m) { return false; }
 #endif
 
 void mce_timer_kick(bool storm);
+void mce_handle_storm(int bank, bool on);
 
 #ifdef CONFIG_ACPI_APEI
 int apei_write_mce(struct mce *m);
-- 
2.35.3