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author | Jan Beulich <jbeulich@suse.com> | 2011-11-18 09:18:41 +0100 |
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committer | Jan Beulich <jbeulich@suse.com> | 2011-11-18 09:18:41 +0100 |
commit | f0b7583fd5a6ea317637693138e060a263b94a2c (patch) | |
tree | 71ac1601ec89f0e328361cda6f7057939565de51 /xen/arch/x86/io_apic.c | |
parent | 6bee8f6b86b7a3388f2891848c4757b04ce76e8c (diff) | |
download | xen-f0b7583fd5a6ea317637693138e060a263b94a2c.tar.gz xen-f0b7583fd5a6ea317637693138e060a263b94a2c.tar.bz2 xen-f0b7583fd5a6ea317637693138e060a263b94a2c.zip |
x86/IO-APIC: refine EOI-ing of migrating level interrupts
Rather than going through all IO-APICs and calling io_apic_eoi_vector()
for the vector in question, just use eoi_IO_APIC_irq().
This in turn allows to eliminate quite a bit of other code.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Diffstat (limited to 'xen/arch/x86/io_apic.c')
-rw-r--r-- | xen/arch/x86/io_apic.c | 70 |
1 files changed, 6 insertions, 64 deletions
diff --git a/xen/arch/x86/io_apic.c b/xen/arch/x86/io_apic.c index 1904034664..ee1d778b7c 100644 --- a/xen/arch/x86/io_apic.c +++ b/xen/arch/x86/io_apic.c @@ -69,10 +69,6 @@ int __read_mostly nr_ioapics; #define ioapic_has_eoi_reg(apic) (mp_ioapics[(apic)].mpc_apicver >= 0x20) -#define io_apic_eoi_vector(apic, vector) io_apic_eoi((apic), (vector), -1) -#define io_apic_eoi_pin(apic, pin) io_apic_eoi((apic), -1, (pin)) - - /* * This is performance-critical, we want to do it O(1) * @@ -213,21 +209,18 @@ static void ioapic_write_entry( spin_unlock_irqrestore(&ioapic_lock, flags); } -/* EOI an IO-APIC entry. One of vector or pin may be -1, indicating that - * it should be worked out using the other. This function expect that the - * ioapic_lock is taken, and interrupts are disabled (or there is a good reason - * not to), and that if both pin and vector are passed, that they refer to the +/* EOI an IO-APIC entry. Vector may be -1, indicating that it should be + * worked out using the pin. This function expects that the ioapic_lock is + * being held, and interrupts are disabled (or there is a good reason not + * to), and that if both pin and vector are passed, that they refer to the * same redirection entry in the IO-APIC. */ static void __io_apic_eoi(unsigned int apic, unsigned int vector, unsigned int pin) { - /* Ensure some useful information is passed in */ - BUG_ON( (vector == -1 && pin == -1) ); - /* Prefer the use of the EOI register if available */ if ( ioapic_has_eoi_reg(apic) ) { /* If vector is unknown, read it from the IO-APIC */ - if ( vector == -1 ) + if ( vector == IRQ_VECTOR_UNASSIGNED ) vector = __ioapic_read_entry(apic, pin, TRUE).vector; *(IO_APIC_BASE(apic)+16) = vector; @@ -239,42 +232,6 @@ static void __io_apic_eoi(unsigned int apic, unsigned int vector, unsigned int p struct IO_APIC_route_entry entry; bool_t need_to_unmask = 0; - /* If pin is unknown, search for it */ - if ( pin == -1 ) - { - unsigned int p; - for ( p = 0; p < nr_ioapic_entries[apic]; ++p ) - { - entry = __ioapic_read_entry(apic, p, TRUE); - if ( entry.vector == vector ) - { - pin = p; - /* break; */ - - /* Here should be a break out of the loop, but at the - * Xen code doesn't actually prevent multiple IO-APIC - * entries being assigned the same vector, so EOI all - * pins which have the correct vector. - * - * Remove the following code when the above assertion - * is fulfilled. */ - __io_apic_eoi(apic, vector, p); - } - } - - /* If search fails, nothing to do */ - - /* if ( pin == -1 ) */ - - /* Because the loop wasn't broken out of (see comment above), - * all relevant pins have been EOI, so we can always return. - * - * Re-instate the if statement above when the Xen logic has been - * fixed.*/ - - return; - } - entry = __ioapic_read_entry(apic, pin, TRUE); if ( ! entry.mask ) @@ -301,17 +258,6 @@ static void __io_apic_eoi(unsigned int apic, unsigned int vector, unsigned int p } } -/* EOI an IO-APIC entry. One of vector or pin may be -1, indicating that - * it should be worked out using the other. This function disables interrupts - * and takes the ioapic_lock */ -static void io_apic_eoi(unsigned int apic, unsigned int vector, unsigned int pin) -{ - unsigned int flags; - spin_lock_irqsave(&ioapic_lock, flags); - __io_apic_eoi(apic, vector, pin); - spin_unlock_irqrestore(&ioapic_lock, flags); -} - /* * Saves all the IO-APIC RTE's */ @@ -1693,11 +1639,7 @@ static void end_level_ioapic_irq(struct irq_desc *desc, u8 vector) /* Manually EOI the old vector if we are moving to the new */ if ( vector && i != vector ) - { - int ioapic; - for (ioapic = 0; ioapic < nr_ioapics; ioapic++) - io_apic_eoi_vector(ioapic, i); - } + eoi_IO_APIC_irq(desc); v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1)); |