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-rw-r--r--include/asm-x86/paravirt.h43
-rw-r--r--include/asm-x86/spinlock.h118
-rw-r--r--include/asm-x86/spinlock_types.h2
-rw-r--r--include/asm-x86/xen/events.h1
-rw-r--r--include/xen/events.h7
5 files changed, 155 insertions, 16 deletions
diff --git a/include/asm-x86/paravirt.h b/include/asm-x86/paravirt.h
index 695ce9383f5..aec9767836b 100644
--- a/include/asm-x86/paravirt.h
+++ b/include/asm-x86/paravirt.h
@@ -325,6 +325,15 @@ struct pv_mmu_ops {
unsigned long phys, pgprot_t flags);
};
+struct raw_spinlock;
+struct pv_lock_ops {
+ int (*spin_is_locked)(struct raw_spinlock *lock);
+ int (*spin_is_contended)(struct raw_spinlock *lock);
+ void (*spin_lock)(struct raw_spinlock *lock);
+ int (*spin_trylock)(struct raw_spinlock *lock);
+ void (*spin_unlock)(struct raw_spinlock *lock);
+};
+
/* This contains all the paravirt structures: we get a convenient
* number for each function using the offset which we use to indicate
* what to patch. */
@@ -335,6 +344,7 @@ struct paravirt_patch_template {
struct pv_irq_ops pv_irq_ops;
struct pv_apic_ops pv_apic_ops;
struct pv_mmu_ops pv_mmu_ops;
+ struct pv_lock_ops pv_lock_ops;
};
extern struct pv_info pv_info;
@@ -344,6 +354,7 @@ extern struct pv_cpu_ops pv_cpu_ops;
extern struct pv_irq_ops pv_irq_ops;
extern struct pv_apic_ops pv_apic_ops;
extern struct pv_mmu_ops pv_mmu_ops;
+extern struct pv_lock_ops pv_lock_ops;
#define PARAVIRT_PATCH(x) \
(offsetof(struct paravirt_patch_template, x) / sizeof(void *))
@@ -1368,6 +1379,37 @@ static inline void __set_fixmap(unsigned /* enum fixed_addresses */ idx,
void _paravirt_nop(void);
#define paravirt_nop ((void *)_paravirt_nop)
+void paravirt_use_bytelocks(void);
+
+#ifdef CONFIG_SMP
+
+static inline int __raw_spin_is_locked(struct raw_spinlock *lock)
+{
+ return PVOP_CALL1(int, pv_lock_ops.spin_is_locked, lock);
+}
+
+static inline int __raw_spin_is_contended(struct raw_spinlock *lock)
+{
+ return PVOP_CALL1(int, pv_lock_ops.spin_is_contended, lock);
+}
+
+static __always_inline void __raw_spin_lock(struct raw_spinlock *lock)
+{
+ PVOP_VCALL1(pv_lock_ops.spin_lock, lock);
+}
+
+static __always_inline int __raw_spin_trylock(struct raw_spinlock *lock)
+{
+ return PVOP_CALL1(int, pv_lock_ops.spin_trylock, lock);
+}
+
+static __always_inline void __raw_spin_unlock(struct raw_spinlock *lock)
+{
+ PVOP_VCALL1(pv_lock_ops.spin_unlock, lock);
+}
+
+#endif
+
/* These all sit in the .parainstructions section to tell us what to patch. */
struct paravirt_patch_site {
u8 *instr; /* original instructions */
@@ -1452,6 +1494,7 @@ static inline unsigned long __raw_local_irq_save(void)
return f;
}
+
/* Make sure as little as possible of this mess escapes. */
#undef PARAVIRT_CALL
#undef __PVOP_CALL
diff --git a/include/asm-x86/spinlock.h b/include/asm-x86/spinlock.h
index 21e89bf92f1..4f9a9861799 100644
--- a/include/asm-x86/spinlock.h
+++ b/include/asm-x86/spinlock.h
@@ -6,7 +6,7 @@
#include <asm/page.h>
#include <asm/processor.h>
#include <linux/compiler.h>
-
+#include <asm/paravirt.h>
/*
* Your basic SMP spinlocks, allowing only a single CPU anywhere
*
@@ -54,21 +54,21 @@
* much between them in performance though, especially as locks are out of line.
*/
#if (NR_CPUS < 256)
-static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
+static inline int __ticket_spin_is_locked(raw_spinlock_t *lock)
{
int tmp = ACCESS_ONCE(lock->slock);
return (((tmp >> 8) & 0xff) != (tmp & 0xff));
}
-static inline int __raw_spin_is_contended(raw_spinlock_t *lock)
+static inline int __ticket_spin_is_contended(raw_spinlock_t *lock)
{
int tmp = ACCESS_ONCE(lock->slock);
return (((tmp >> 8) & 0xff) - (tmp & 0xff)) > 1;
}
-static __always_inline void __raw_spin_lock(raw_spinlock_t *lock)
+static __always_inline void __ticket_spin_lock(raw_spinlock_t *lock)
{
short inc = 0x0100;
@@ -87,9 +87,7 @@ static __always_inline void __raw_spin_lock(raw_spinlock_t *lock)
: "memory", "cc");
}
-#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
-
-static __always_inline int __raw_spin_trylock(raw_spinlock_t *lock)
+static __always_inline int __ticket_spin_trylock(raw_spinlock_t *lock)
{
int tmp;
short new;
@@ -110,7 +108,7 @@ static __always_inline int __raw_spin_trylock(raw_spinlock_t *lock)
return tmp;
}
-static __always_inline void __raw_spin_unlock(raw_spinlock_t *lock)
+static __always_inline void __ticket_spin_unlock(raw_spinlock_t *lock)
{
asm volatile(UNLOCK_LOCK_PREFIX "incb %0"
: "+m" (lock->slock)
@@ -118,21 +116,21 @@ static __always_inline void __raw_spin_unlock(raw_spinlock_t *lock)
: "memory", "cc");
}
#else
-static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
+static inline int __ticket_spin_is_locked(raw_spinlock_t *lock)
{
int tmp = ACCESS_ONCE(lock->slock);
return (((tmp >> 16) & 0xffff) != (tmp & 0xffff));
}
-static inline int __raw_spin_is_contended(raw_spinlock_t *lock)
+static inline int __ticket_spin_is_contended(raw_spinlock_t *lock)
{
int tmp = ACCESS_ONCE(lock->slock);
return (((tmp >> 16) & 0xffff) - (tmp & 0xffff)) > 1;
}
-static __always_inline void __raw_spin_lock(raw_spinlock_t *lock)
+static __always_inline void __ticket_spin_lock(raw_spinlock_t *lock)
{
int inc = 0x00010000;
int tmp;
@@ -153,9 +151,7 @@ static __always_inline void __raw_spin_lock(raw_spinlock_t *lock)
: "memory", "cc");
}
-#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
-
-static __always_inline int __raw_spin_trylock(raw_spinlock_t *lock)
+static __always_inline int __ticket_spin_trylock(raw_spinlock_t *lock)
{
int tmp;
int new;
@@ -177,7 +173,7 @@ static __always_inline int __raw_spin_trylock(raw_spinlock_t *lock)
return tmp;
}
-static __always_inline void __raw_spin_unlock(raw_spinlock_t *lock)
+static __always_inline void __ticket_spin_unlock(raw_spinlock_t *lock)
{
asm volatile(UNLOCK_LOCK_PREFIX "incw %0"
: "+m" (lock->slock)
@@ -186,6 +182,98 @@ static __always_inline void __raw_spin_unlock(raw_spinlock_t *lock)
}
#endif
+#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
+
+#ifdef CONFIG_PARAVIRT
+/*
+ * Define virtualization-friendly old-style lock byte lock, for use in
+ * pv_lock_ops if desired.
+ *
+ * This differs from the pre-2.6.24 spinlock by always using xchgb
+ * rather than decb to take the lock; this allows it to use a
+ * zero-initialized lock structure. It also maintains a 1-byte
+ * contention counter, so that we can implement
+ * __byte_spin_is_contended.
+ */
+struct __byte_spinlock {
+ s8 lock;
+ s8 spinners;
+};
+
+static inline int __byte_spin_is_locked(raw_spinlock_t *lock)
+{
+ struct __byte_spinlock *bl = (struct __byte_spinlock *)lock;
+ return bl->lock != 0;
+}
+
+static inline int __byte_spin_is_contended(raw_spinlock_t *lock)
+{
+ struct __byte_spinlock *bl = (struct __byte_spinlock *)lock;
+ return bl->spinners != 0;
+}
+
+static inline void __byte_spin_lock(raw_spinlock_t *lock)
+{
+ struct __byte_spinlock *bl = (struct __byte_spinlock *)lock;
+ s8 val = 1;
+
+ asm("1: xchgb %1, %0\n"
+ " test %1,%1\n"
+ " jz 3f\n"
+ " " LOCK_PREFIX "incb %2\n"
+ "2: rep;nop\n"
+ " cmpb $1, %0\n"
+ " je 2b\n"
+ " " LOCK_PREFIX "decb %2\n"
+ " jmp 1b\n"
+ "3:"
+ : "+m" (bl->lock), "+q" (val), "+m" (bl->spinners): : "memory");
+}
+
+static inline int __byte_spin_trylock(raw_spinlock_t *lock)
+{
+ struct __byte_spinlock *bl = (struct __byte_spinlock *)lock;
+ u8 old = 1;
+
+ asm("xchgb %1,%0"
+ : "+m" (bl->lock), "+q" (old) : : "memory");
+
+ return old == 0;
+}
+
+static inline void __byte_spin_unlock(raw_spinlock_t *lock)
+{
+ struct __byte_spinlock *bl = (struct __byte_spinlock *)lock;
+ smp_wmb();
+ bl->lock = 0;
+}
+#else /* !CONFIG_PARAVIRT */
+static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
+{
+ return __ticket_spin_is_locked(lock);
+}
+
+static inline int __raw_spin_is_contended(raw_spinlock_t *lock)
+{
+ return __ticket_spin_is_contended(lock);
+}
+
+static __always_inline void __raw_spin_lock(raw_spinlock_t *lock)
+{
+ __ticket_spin_lock(lock);
+}
+
+static __always_inline int __raw_spin_trylock(raw_spinlock_t *lock)
+{
+ return __ticket_spin_trylock(lock);
+}
+
+static __always_inline void __raw_spin_unlock(raw_spinlock_t *lock)
+{
+ __ticket_spin_unlock(lock);
+}
+#endif /* CONFIG_PARAVIRT */
+
static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock)
{
while (__raw_spin_is_locked(lock))
diff --git a/include/asm-x86/spinlock_types.h b/include/asm-x86/spinlock_types.h
index 9029cf78cf5..06c071c9eee 100644
--- a/include/asm-x86/spinlock_types.h
+++ b/include/asm-x86/spinlock_types.h
@@ -5,7 +5,7 @@
# error "please don't include this file directly"
#endif
-typedef struct {
+typedef struct raw_spinlock {
unsigned int slock;
} raw_spinlock_t;
diff --git a/include/asm-x86/xen/events.h b/include/asm-x86/xen/events.h
index f8d57ea1f05..8ded7472002 100644
--- a/include/asm-x86/xen/events.h
+++ b/include/asm-x86/xen/events.h
@@ -5,6 +5,7 @@ enum ipi_vector {
XEN_RESCHEDULE_VECTOR,
XEN_CALL_FUNCTION_VECTOR,
XEN_CALL_FUNCTION_SINGLE_VECTOR,
+ XEN_SPIN_UNLOCK_VECTOR,
XEN_NR_IPIS,
};
diff --git a/include/xen/events.h b/include/xen/events.h
index 67c4436554a..4680ff3fbc9 100644
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -44,4 +44,11 @@ extern void notify_remote_via_irq(int irq);
extern void xen_irq_resume(void);
+/* Clear an irq's pending state, in preparation for polling on it */
+void xen_clear_irq_pending(int irq);
+
+/* Poll waiting for an irq to become pending. In the usual case, the
+ irq will be disabled so it won't deliver an interrupt. */
+void xen_poll_irq(int irq);
+
#endif /* _XEN_EVENTS_H */
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-30 19:34:14 +0000