Date: Thu, 23 Jul 2026 10:01:18 +0000 From: Olivier Certner <olce@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Cc: Konstantin Belousov <kib@FreeBSD.org> Subject: git: a9e4131375f8 - stable/14 - x86/local_apic.c: add lapic_maxlvt() helper Message-ID: <6a61e66e.3cfdd.36e8ab3a@gitrepo.freebsd.org>
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The branch stable/14 has been updated by olce: URL: https://cgit.FreeBSD.org/src/commit/?id=a9e4131375f87c6933f8321adde95d14f6d3764d commit a9e4131375f87c6933f8321adde95d14f6d3764d Author: Konstantin Belousov <kib@FreeBSD.org> AuthorDate: 2026-01-19 12:50:09 +0000 Commit: Olivier Certner <olce@FreeBSD.org> CommitDate: 2026-07-23 09:59:16 +0000 x86/local_apic.c: add lapic_maxlvt() helper that calculates the max index of the present LVT entry from the value of the LAPIC version register. Reviewed by: markj Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D54773 (cherry picked from commit ad5e3cb950344f9822dbbd90f5ac7c256f97fa4c) --- sys/x86/x86/local_apic.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/sys/x86/x86/local_apic.c b/sys/x86/x86/local_apic.c index 2636b87e78b3..ca2411c112a0 100644 --- a/sys/x86/x86/local_apic.c +++ b/sys/x86/x86/local_apic.c @@ -320,6 +320,16 @@ SYSCTL_INT(_hw_apic, OID_AUTO, ds_idle_timeout, CTLFLAG_RWTUN, static void lapic_calibrate_initcount(struct lapic *la); +/* + * Calculate the max index of the present LVT entry from the value of + * the LAPIC version register. + */ +static int +lapic_maxlvt(uint32_t version) +{ + return ((version & APIC_VER_MAXLVT) >> MAXLVTSHIFT); +} + /* * Use __nosanitizethread to exempt the LAPIC I/O accessors from KCSan * instrumentation. Otherwise, if x2APIC is not available, use of the global @@ -761,7 +771,7 @@ lapic_dump(const char* str) int i; version = lapic_read32(LAPIC_VERSION); - maxlvt = (version & APIC_VER_MAXLVT) >> MAXLVTSHIFT; + maxlvt = lapic_maxlvt(version); printf("cpu%d %s:\n", PCPU_GET(cpuid), str); printf(" ID: 0x%08x VER: 0x%08x LDR: 0x%08x DFR: 0x%08x", lapic_read32(LAPIC_ID), version, @@ -842,7 +852,7 @@ lapic_setup(int boot) la = &lapics[lapic_id()]; KASSERT(la->la_present, ("missing APIC structure")); version = lapic_read32(LAPIC_VERSION); - maxlvt = (version & APIC_VER_MAXLVT) >> MAXLVTSHIFT; + maxlvt = lapic_maxlvt(version); /* Initialize the TPR to allow all interrupts. */ lapic_set_tpr(0); @@ -1003,7 +1013,7 @@ lapic_enable_pmc(void) #endif /* Fail if the PMC LVT is not present. */ - maxlvt = (lapic_read32(LAPIC_VERSION) & APIC_VER_MAXLVT) >> MAXLVTSHIFT; + maxlvt = lapic_maxlvt(lapic_read32(LAPIC_VERSION)); if (maxlvt < APIC_LVT_PMC) return (0); @@ -1030,7 +1040,7 @@ lapic_disable_pmc(void) #endif /* Fail if the PMC LVT is not present. */ - maxlvt = (lapic_read32(LAPIC_VERSION) & APIC_VER_MAXLVT) >> MAXLVTSHIFT; + maxlvt = lapic_maxlvt(lapic_read32(LAPIC_VERSION)); if (maxlvt < APIC_LVT_PMC) return; @@ -1965,7 +1975,7 @@ DB_SHOW_COMMAND_FLAGS(lapic, db_show_lapic, DB_CMD_MEMSAFE) v = lapic_read32(LAPIC_VERSION); db_printf("version = %d.%d\n", (v & APIC_VER_VERSION) >> 4, v & 0xf); - db_printf("max LVT = %d\n", (v & APIC_VER_MAXLVT) >> MAXLVTSHIFT); + db_printf("max LVT = %d\n", lapic_maxlvt(v)); v = lapic_read32(LAPIC_SVR); db_printf("SVR = %02x (%s)\n", v & APIC_SVR_VECTOR, v & APIC_SVR_ENABLE ? "enabled" : "disabled");home | help
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