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authorLinus Torvalds <torvalds@linux-foundation.org>2018-04-02 22:38:43 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2018-04-02 22:38:43 +0200
commit2451d1e59d5a154a42bcf02e0bfeebb01d8df1e0 (patch)
tree3f540d996f91441d189323a6452a39dc1db7c8ac /arch/x86/kernel/apic
parentMerge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/ke... (diff)
parentx86/apic: Finish removing unused callbacks (diff)
downloadlinux-2451d1e59d5a154a42bcf02e0bfeebb01d8df1e0.tar.xz
linux-2451d1e59d5a154a42bcf02e0bfeebb01d8df1e0.zip
Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 apic updates from Ingo Molnar: "The main x86 APIC/IOAPIC changes in this cycle were: - Robustify kexec support to more carefully restore IRQ hardware state before calling into kexec/kdump kernels. (Baoquan He) - Clean up the local APIC code a bit (Dou Liyang) - Remove unused callbacks (David Rientjes)" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Finish removing unused callbacks x86/apic: Drop logical_smp_processor_id() inline x86/apic: Modernize the pending interrupt code x86/apic: Move pending interrupt check code into it's own function x86/apic: Set up through-local-APIC mode on the boot CPU if 'noapic' specified x86/apic: Rename variables and functions related to x86_io_apic_ops x86/apic: Remove the (now) unused disable_IO_APIC() function x86/apic: Fix restoring boot IRQ mode in reboot and kexec/kdump x86/apic: Split disable_IO_APIC() into two functions to fix CONFIG_KEXEC_JUMP=y x86/apic: Split out restore_boot_irq_mode() from disable_IO_APIC() x86/apic: Make setup_local_APIC() static x86/apic: Simplify init_bsp_APIC() usage x86/x2apic: Mark set_x2apic_phys_mode() as __init
Diffstat (limited to 'arch/x86/kernel/apic')
-rw-r--r--arch/x86/kernel/apic/apic.c111
-rw-r--r--arch/x86/kernel/apic/io_apic.c16
-rw-r--r--arch/x86/kernel/apic/x2apic_phys.c2
3 files changed, 65 insertions, 64 deletions
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index b203af0855b5..2aabd4cb0e3f 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1408,22 +1408,69 @@ static void lapic_setup_esr(void)
oldvalue, value);
}
+static void apic_pending_intr_clear(void)
+{
+ long long max_loops = cpu_khz ? cpu_khz : 1000000;
+ unsigned long long tsc = 0, ntsc;
+ unsigned int queued;
+ unsigned long value;
+ int i, j, acked = 0;
+
+ if (boot_cpu_has(X86_FEATURE_TSC))
+ tsc = rdtsc();
+ /*
+ * After a crash, we no longer service the interrupts and a pending
+ * interrupt from previous kernel might still have ISR bit set.
+ *
+ * Most probably by now CPU has serviced that pending interrupt and
+ * it might not have done the ack_APIC_irq() because it thought,
+ * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
+ * does not clear the ISR bit and cpu thinks it has already serivced
+ * the interrupt. Hence a vector might get locked. It was noticed
+ * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
+ */
+ do {
+ queued = 0;
+ for (i = APIC_ISR_NR - 1; i >= 0; i--)
+ queued |= apic_read(APIC_IRR + i*0x10);
+
+ for (i = APIC_ISR_NR - 1; i >= 0; i--) {
+ value = apic_read(APIC_ISR + i*0x10);
+ for_each_set_bit(j, &value, 32) {
+ ack_APIC_irq();
+ acked++;
+ }
+ }
+ if (acked > 256) {
+ pr_err("LAPIC pending interrupts after %d EOI\n", acked);
+ break;
+ }
+ if (queued) {
+ if (boot_cpu_has(X86_FEATURE_TSC) && cpu_khz) {
+ ntsc = rdtsc();
+ max_loops = (cpu_khz << 10) - (ntsc - tsc);
+ } else {
+ max_loops--;
+ }
+ }
+ } while (queued && max_loops > 0);
+ WARN_ON(max_loops <= 0);
+}
+
/**
* setup_local_APIC - setup the local APIC
*
* Used to setup local APIC while initializing BSP or bringing up APs.
* Always called with preemption disabled.
*/
-void setup_local_APIC(void)
+static void setup_local_APIC(void)
{
int cpu = smp_processor_id();
- unsigned int value, queued;
- int i, j, acked = 0;
- unsigned long long tsc = 0, ntsc;
- long long max_loops = cpu_khz ? cpu_khz : 1000000;
+ unsigned int value;
+#ifdef CONFIG_X86_32
+ int logical_apicid, ldr_apicid;
+#endif
- if (boot_cpu_has(X86_FEATURE_TSC))
- tsc = rdtsc();
if (disable_apic) {
disable_ioapic_support();
@@ -1460,11 +1507,11 @@ void setup_local_APIC(void)
* initialized during get_smp_config(), make sure it matches the
* actual value.
*/
- i = early_per_cpu(x86_cpu_to_logical_apicid, cpu);
- WARN_ON(i != BAD_APICID && i != logical_smp_processor_id());
+ logical_apicid = early_per_cpu(x86_cpu_to_logical_apicid, cpu);
+ ldr_apicid = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR));
+ WARN_ON(logical_apicid != BAD_APICID && logical_apicid != ldr_apicid);
/* always use the value from LDR */
- early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
- logical_smp_processor_id();
+ early_per_cpu(x86_cpu_to_logical_apicid, cpu) = ldr_apicid;
#endif
/*
@@ -1475,45 +1522,7 @@ void setup_local_APIC(void)
value &= ~APIC_TPRI_MASK;
apic_write(APIC_TASKPRI, value);
- /*
- * After a crash, we no longer service the interrupts and a pending
- * interrupt from previous kernel might still have ISR bit set.
- *
- * Most probably by now CPU has serviced that pending interrupt and
- * it might not have done the ack_APIC_irq() because it thought,
- * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
- * does not clear the ISR bit and cpu thinks it has already serivced
- * the interrupt. Hence a vector might get locked. It was noticed
- * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
- */
- do {
- queued = 0;
- for (i = APIC_ISR_NR - 1; i >= 0; i--)
- queued |= apic_read(APIC_IRR + i*0x10);
-
- for (i = APIC_ISR_NR - 1; i >= 0; i--) {
- value = apic_read(APIC_ISR + i*0x10);
- for (j = 31; j >= 0; j--) {
- if (value & (1<<j)) {
- ack_APIC_irq();
- acked++;
- }
- }
- }
- if (acked > 256) {
- printk(KERN_ERR "LAPIC pending interrupts after %d EOI\n",
- acked);
- break;
- }
- if (queued) {
- if (boot_cpu_has(X86_FEATURE_TSC) && cpu_khz) {
- ntsc = rdtsc();
- max_loops = (cpu_khz << 10) - (ntsc - tsc);
- } else
- max_loops--;
- }
- } while (queued && max_loops > 0);
- WARN_ON(max_loops <= 0);
+ apic_pending_intr_clear();
/*
* Now that we are all set up, enable the APIC
@@ -1570,7 +1579,7 @@ void setup_local_APIC(void)
* TODO: set up through-local-APIC from through-I/O-APIC? --macro
*/
value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
- if (!cpu && (pic_mode || !value)) {
+ if (!cpu && (pic_mode || !value || skip_ioapic_setup)) {
value = APIC_DM_EXTINT;
apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n", cpu);
} else {
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 7c5538769f7e..7553819c74c3 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -587,7 +587,7 @@ static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
mpc_ioapic_id(apic), pin);
}
-static void clear_IO_APIC (void)
+void clear_IO_APIC (void)
{
int apic, pin;
@@ -1410,7 +1410,7 @@ void __init enable_IO_APIC(void)
clear_IO_APIC();
}
-void native_disable_io_apic(void)
+void native_restore_boot_irq_mode(void)
{
/*
* If the i8259 is routed through an IOAPIC
@@ -1438,20 +1438,12 @@ void native_disable_io_apic(void)
disconnect_bsp_APIC(ioapic_i8259.pin != -1);
}
-/*
- * Not an __init, needed by the reboot code
- */
-void disable_IO_APIC(void)
+void restore_boot_irq_mode(void)
{
- /*
- * Clear the IO-APIC before rebooting:
- */
- clear_IO_APIC();
-
if (!nr_legacy_irqs())
return;
- x86_io_apic_ops.disable();
+ x86_apic_ops.restore();
}
#ifdef CONFIG_X86_32
diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c
index f8d9d69994e6..e2829bf40e4a 100644
--- a/arch/x86/kernel/apic/x2apic_phys.c
+++ b/arch/x86/kernel/apic/x2apic_phys.c
@@ -14,7 +14,7 @@ int x2apic_phys;
static struct apic apic_x2apic_phys;
-static int set_x2apic_phys_mode(char *arg)
+static int __init set_x2apic_phys_mode(char *arg)
{
x2apic_phys = 1;
return 0;