multicalls.h
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#ifndef _XEN_MULTICALLS_H
#define _XEN_MULTICALLS_H
#include <trace/events/xen.h>
#include "xen-ops.h"
/* Multicalls */
struct multicall_space
{
struct multicall_entry *mc;
void *args;
};
/* Allocate room for a multicall and its args */
struct multicall_space __xen_mc_entry(size_t args);
DECLARE_PER_CPU(unsigned long, xen_mc_irq_flags);
/* Call to start a batch of multiple __xen_mc_entry()s. Must be
paired with xen_mc_issue() */
static inline void xen_mc_batch(void)
{
unsigned long flags;
/* need to disable interrupts until this entry is complete */
local_irq_save(flags);
trace_xen_mc_batch(paravirt_get_lazy_mode());
__this_cpu_write(xen_mc_irq_flags, flags);
}
static inline struct multicall_space xen_mc_entry(size_t args)
{
xen_mc_batch();
return __xen_mc_entry(args);
}
/* Flush all pending multicalls */
void xen_mc_flush(void);
/* Issue a multicall if we're not in a lazy mode */
static inline void xen_mc_issue(unsigned mode)
{
trace_xen_mc_issue(mode);
if ((paravirt_get_lazy_mode() & mode) == 0)
xen_mc_flush();
/* restore flags saved in xen_mc_batch */
local_irq_restore(this_cpu_read(xen_mc_irq_flags));
}
/* Set up a callback to be called when the current batch is flushed */
void xen_mc_callback(void (*fn)(void *), void *data);
/*
* Try to extend the arguments of the previous multicall command. The
* previous command's op must match. If it does, then it attempts to
* extend the argument space allocated to the multicall entry by
* arg_size bytes.
*
* The returned multicall_space will return with mc pointing to the
* command on success, or NULL on failure, and args pointing to the
* newly allocated space.
*/
struct multicall_space xen_mc_extend_args(unsigned long op, size_t arg_size);
#endif /* _XEN_MULTICALLS_H */