mirror_zfs/include/os/linux/kernel/linux/page_compat.h
Brian Behlendorf 3e29e1971b
Linux 5.9 compat: NR_SLAB_RECLAIMABLE
Commit dcdc12e added compatibility code to treat NR_SLAB_RECLAIMABLE_B
as if it were the same as NR_SLAB_RECLAIMABLE.  However, the new value
is in bytes while the old value was in pages which means they are not
interchangeable.

The only place the reclaimable slab size is used is as a component of
the calculation done by arc_free_memory().  This function returns the
amount of memory the ARC considers to be free or reclaimable at little
cost.  Rather than switch to a new interface to get this value it has
been removed it from the calculation.  It is normally a minor component
compared to the number of inactive or free pages, and removing it
aligns the behavior with the FreeBSD version of arc_free_memory().

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Coleman Kane <ckane@colemankane.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #10834
2020-08-29 20:57:45 -07:00

68 lines
2.3 KiB
C

#ifndef _ZFS_PAGE_COMPAT_H
#define _ZFS_PAGE_COMPAT_H
/*
* We have various enum members moving between two separate enum types,
* and accessed by different functions at various times. Centralise the
* insanity.
*
* < v4.8: all enums in zone_stat_item, via global_page_state()
* v4.8: some enums moved to node_stat_item, global_node_page_state() introduced
* v4.13: some enums moved from zone_stat_item to node_state_item
* v4.14: global_page_state() rename to global_zone_page_state()
*
* The defines used here are created by config/kernel-global_page_state.m4
*/
/*
* Create our own accessor functions to follow the Linux API changes
*/
#if defined(ZFS_GLOBAL_ZONE_PAGE_STATE)
/* global_zone_page_state() introduced */
#if defined(ZFS_ENUM_NODE_STAT_ITEM_NR_FILE_PAGES)
#define nr_file_pages() global_node_page_state(NR_FILE_PAGES)
#else
#define nr_file_pages() global_zone_page_state(NR_FILE_PAGES)
#endif
#if defined(ZFS_ENUM_NODE_STAT_ITEM_NR_INACTIVE_ANON)
#define nr_inactive_anon_pages() global_node_page_state(NR_INACTIVE_ANON)
#else
#define nr_inactive_anon_pages() global_zone_page_state(NR_INACTIVE_ANON)
#endif
#if defined(ZFS_ENUM_NODE_STAT_ITEM_NR_INACTIVE_FILE)
#define nr_inactive_file_pages() global_node_page_state(NR_INACTIVE_FILE)
#else
#define nr_inactive_file_pages() global_zone_page_state(NR_INACTIVE_FILE)
#endif
#elif defined(ZFS_GLOBAL_NODE_PAGE_STATE)
/* global_node_page_state() introduced */
#if defined(ZFS_ENUM_NODE_STAT_ITEM_NR_FILE_PAGES)
#define nr_file_pages() global_node_page_state(NR_FILE_PAGES)
#else
#define nr_file_pages() global_page_state(NR_FILE_PAGES)
#endif
#if defined(ZFS_ENUM_NODE_STAT_ITEM_NR_INACTIVE_ANON)
#define nr_inactive_anon_pages() global_node_page_state(NR_INACTIVE_ANON)
#else
#define nr_inactive_anon_pages() global_page_state(NR_INACTIVE_ANON)
#endif
#if defined(ZFS_ENUM_NODE_STAT_ITEM_NR_INACTIVE_FILE)
#define nr_inactive_file_pages() global_node_page_state(NR_INACTIVE_FILE)
#else
#define nr_inactive_file_pages() global_page_state(NR_INACTIVE_FILE)
#endif
#else
/* global_page_state() only */
#define nr_file_pages() global_page_state(NR_FILE_PAGES)
#define nr_inactive_anon_pages() global_page_state(NR_INACTIVE_ANON)
#define nr_inactive_file_pages() global_page_state(NR_INACTIVE_FILE)
#endif /* ZFS_GLOBAL_ZONE_PAGE_STATE */
#endif /* _ZFS_PAGE_COMPAT_H */