migration(3)migration(3)NAME
migr_range_migrate, migr_policy_args_init - user migration operations
SYNOPSIS
#include <sys/types.h>
#include <sys/pmo.h>
typedef struct migr_policy_uparms {
__uint64_t migr_base_enabled :1,
migr_base_threshold :8,
migr_freeze_enabled :1,
migr_freeze_threshold :8,
migr_melt_enabled :1,
migr_melt_threshold :8,
migr_enqonfail_enabled :1,
migr_dampening_enabled :1,
migr_dampening_factor :8,
migr_refcnt_enabled :1,
migr_resv_bits :4;
} migr_policy_uparms_t;
int migr_range_migrate(void* base_addr, size_t length,
pmo_handle_t pmo_handle)
void migr_policy_args_init(migr_policy_uparms_t* p)
DESCRIPTION
migr_range_migrate migrates a range of memory to the node where the
pmo_handle has been placed. The pmo_handle can be a placed MLD or an
MLDSET with at least one placed MLD contained within it.
migr_policy_args_init fills a migration parameter structure with default
values. This function is applicable to Origin 2000/200 systems, and has
no effect on other Origin systems.
migr_range_migrate attempts to move all pages that have been faulted in
within the range of base_addr plus length. If base_addr is not on a page
boundary, the actual start address of the migration is rounded down to
the previous page boundary. If base_addr+length is not on a page
boundary, the actual migration length is adjusted by rounding up to end
on the next page boundary. If a page cannot be migrated, it is skipped
and the next page is attempted. If the destination node does not have
enough available free memory to migrate the new pages into, the migration
operation is ended and error is returned (see below). It is usually not
possible to migrate every single page of user memory for a variety of
reasons. A page that is set up for DMA I/O is an example of an un-
migratable page. A page set up for fetchops, a pinned page, a page not
faulted in, and a page that is shared with unrelated processes will not
migrate. In some cases of a physical page shared with several virtual
addresses, it may be migratable if the migrating process can obtain all
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migration(3)migration(3)
the necessary locks. In situations where pages are skipped over, these
skipped pages remain on their current node location for the duration of
their existence.
migr_range_migrate will fail and some or all of the specified memory may
not be successfully migrated if one or more of the following are true:
EFAULT Arguments could not be copied into kernel space.
EINVAL The specified pmo_handle is invalid or does not exist.
EINVAL The specified pmo_handle is not placed on a valid node.
EINVAL Memory to migrate is not a user segment address.
ENOMEM The user address is not mapped.
EBUSY One or more of the user pages is already in the process of
migrating.
EBUSY The anonymous page being migrated is no longer owned by
the caller.
EBUSY One of the pages to migrate has raw I/O in progress.
EBUSY One of the pages to migrate is on its way back from
backing store.
EBUSY One of the pages is marked BAD and cannot be moved.
EBUSY One of the pages has its RMAP lock set and cannot be
moved.
EBUSY One of the pages could not achieve a lock on all shared
page table entries.
EBUSY One of the pages has no page table entry.
EBUSY One of the pages has a mismatch of shared use and reverse
map entries.
EBUSY One of the pages has a lock set from another shared
virtual address.
EBUSY One of the vnode pages has changed while migrating.
ENOMEM There is not enough free memory to migrate the specified
memory.
ENOTSUP Memory locality domains are not supported on this system
architecture.
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migration(3)migration(3)SEE ALSOnuma(5), mmci(5), mld(3c), mldset(3c), pm(3c).
DIAGNOSTICS
Upon successful completion, migr_range_migrate returns 0. Otherwise, a
value of -1 is returned and errno is set to indicate the error.
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