Provide infrastructure to auto-configure to enum and API changes in the
global page stats used for our free memory calculations.
arc_free_memory has been broken since an API change in Linux v3.14:
2016-07-28 v4.8
599d0c95 mm, vmscan: move LRU lists to node
2016-07-28 v4.8
75ef7184 mm, vmstat: add infrastructure for per-node
vmstats
These commits moved some of global_page_state() into
global_node_page_state(). The API change was particularly egregious as,
instead of breaking the old code, it silently did the wrong thing and we
continued using global_page_state() where we should have been using
global_node_page_state(), thus indexing into the wrong array via
NR_SLAB_RECLAIMABLE et al.
There have been further API changes along the way:
2017-07-06 v4.13
385386cf mm: vmstat: move slab statistics from zone to
node counters
2017-09-06 v4.14
c41f012a mm: rename global_page_state to
global_zone_page_state
...and various (incomplete, as it turns out) attempts to accomodate
these changes in ZoL:
2017-08-24
2209e409 Linux 4.8+ compatibility fix for vm stats
2017-09-16
787acae0 Linux 3.14 compat: IO acct, global_page_state, etc
2017-09-19
661907e6 Linux 4.14 compat: IO acct, global_page_state, etc
The config infrastructure provided here resolves these issues going back
to the original API change in v3.14 and is robust against further Linux
changes in this area.
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Closes #7170
--- /dev/null
+dnl #
+dnl # 4.8 API change
+dnl #
+dnl # 75ef71840539 mm, vmstat: add infrastructure for per-node vmstats
+dnl # 599d0c954f91 mm, vmscan: move LRU lists to node
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_NODE_PAGE_STATE], [
+ AC_MSG_CHECKING([whether global_node_page_state() exists])
+ ZFS_LINUX_TRY_COMPILE([
+ #include <linux/mm.h>
+ #include <linux/vmstat.h>
+ ],[
+ (void) global_node_page_state(0);
+ ],[
+ AC_MSG_RESULT(yes)
+ AC_DEFINE(ZFS_GLOBAL_NODE_PAGE_STATE, 1, [global_node_page_state() exists])
+ ],[
+ AC_MSG_RESULT(no)
+ ])
+])
+
+dnl #
+dnl # 4.14 API change
+dnl #
+dnl # c41f012ade0b mm: rename global_page_state to global_zone_page_state
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_ZONE_PAGE_STATE], [
+ AC_MSG_CHECKING([whether global_zone_page_state() exists])
+ ZFS_LINUX_TRY_COMPILE([
+ #include <linux/mm.h>
+ #include <linux/vmstat.h>
+ ],[
+ (void) global_zone_page_state(0);
+ ],[
+ AC_MSG_RESULT(yes)
+ AC_DEFINE(ZFS_GLOBAL_ZONE_PAGE_STATE, 1, [global_zone_page_state() exists])
+ ],[
+ AC_MSG_RESULT(no)
+ ])
+])
+
+dnl #
+dnl # Create a define and autoconf variable for an enum member
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_ENUM_MEMBER], [
+ AC_MSG_CHECKING([whether enum $2 contains $1])
+ AS_IF([AC_TRY_COMMAND("${srcdir}/scripts/enum-extract.pl" "$2" "$3" | egrep -qx $1)],[
+ AC_MSG_RESULT([yes])
+ AC_DEFINE(m4_join([_], [ZFS_ENUM], m4_toupper($2), $1), 1, [enum $2 contains $1])
+ m4_join([_], [ZFS_ENUM], m4_toupper($2), $1)=1
+ ],[
+ AC_MSG_RESULT([no])
+ ])
+])
+
+dnl #
+dnl # Sanity check helpers
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_ERROR],[
+ AC_MSG_RESULT(no)
+ AC_MSG_RESULT([$1 in either node_stat_item or zone_stat_item: $2])
+ AC_MSG_RESULT([configure needs updating, see: config/kernel-global_page_state.m4])
+ AC_MSG_FAILURE([SHUT 'ER DOWN CLANCY, SHE'S PUMPIN' MUD!])
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_CHECK], [
+ enum_check_a="m4_join([_], [$ZFS_ENUM_NODE_STAT_ITEM], $1)"
+ enum_check_b="m4_join([_], [$ZFS_ENUM_ZONE_STAT_ITEM], $1)"
+ AS_IF([test -n "$enum_check_a" -a -n "$enum_check_b"],[
+ ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_ERROR([$1], [DUPLICATE])
+ ])
+ AS_IF([test -z "$enum_check_a" -a -z "$enum_check_b"],[
+ ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_ERROR([$1], [NOT FOUND])
+ ])
+])
+
+dnl #
+dnl # Ensure the config tests are finding one and only one of each enum of interest
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_ZONE_PAGE_STATE_SANITY], [
+ AC_MSG_CHECKING([global_page_state enums are sane])
+
+ ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_CHECK([NR_FILE_PAGES])
+ ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_CHECK([NR_INACTIVE_ANON])
+ ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_CHECK([NR_INACTIVE_FILE])
+ ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_CHECK([NR_SLAB_RECLAIMABLE])
+
+ AC_MSG_RESULT(yes)
+])
+
+dnl #
+dnl # enum members in which we're interested
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_PAGE_STATE], [
+ ZFS_AC_KERNEL_GLOBAL_NODE_PAGE_STATE
+ ZFS_AC_KERNEL_GLOBAL_ZONE_PAGE_STATE
+
+ ZFS_AC_KERNEL_ENUM_MEMBER([NR_FILE_PAGES], [node_stat_item], [$LINUX/include/linux/mmzone.h])
+ ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_ANON], [node_stat_item], [$LINUX/include/linux/mmzone.h])
+ ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_FILE], [node_stat_item], [$LINUX/include/linux/mmzone.h])
+ ZFS_AC_KERNEL_ENUM_MEMBER([NR_SLAB_RECLAIMABLE], [node_stat_item], [$LINUX/include/linux/mmzone.h])
+
+ ZFS_AC_KERNEL_ENUM_MEMBER([NR_FILE_PAGES], [zone_stat_item], [$LINUX/include/linux/mmzone.h])
+ ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_ANON], [zone_stat_item], [$LINUX/include/linux/mmzone.h])
+ ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_FILE], [zone_stat_item], [$LINUX/include/linux/mmzone.h])
+ ZFS_AC_KERNEL_ENUM_MEMBER([NR_SLAB_RECLAIMABLE], [zone_stat_item], [$LINUX/include/linux/mmzone.h])
+
+ ZFS_AC_KERNEL_GLOBAL_ZONE_PAGE_STATE_SANITY
+])
+++ /dev/null
-dnl #
-dnl # 4.8 API change
-dnl # kernel vm counters change
-dnl #
-AC_DEFUN([ZFS_AC_KERNEL_VM_NODE_STAT], [
- AC_MSG_CHECKING([whether to use vm_node_stat based fn's])
- ZFS_LINUX_TRY_COMPILE([
- #include <linux/mm.h>
- #include <linux/vmstat.h>
- ],[
- int a __attribute__ ((unused)) = NR_VM_NODE_STAT_ITEMS;
- long x __attribute__ ((unused)) =
- atomic_long_read(&vm_node_stat[0]);
- (void) global_node_page_state(0);
- ],[
- AC_MSG_RESULT(yes)
- AC_DEFINE(ZFS_GLOBAL_NODE_PAGE_STATE, 1,
- [using global_node_page_state()])
- ],[
- AC_MSG_RESULT(no)
- ])
-])
ZFS_AC_KERNEL_RENAME_WANTS_FLAGS
ZFS_AC_KERNEL_HAVE_GENERIC_SETXATTR
ZFS_AC_KERNEL_CURRENT_TIME
- ZFS_AC_KERNEL_VM_NODE_STAT
+ ZFS_AC_KERNEL_GLOBAL_PAGE_STATE
ZFS_AC_KERNEL_ACL_HAS_REFCOUNT
AS_IF([test "$LINUX_OBJ" != "$LINUX"], [
$(top_srcdir)/include/linux/kmap_compat.h \
$(top_srcdir)/include/linux/simd_x86.h \
$(top_srcdir)/include/linux/simd_aarch64.h \
- $(top_srcdir)/include/linux/mod_compat.h
+ $(top_srcdir)/include/linux/mod_compat.h \
+ $(top_srcdir)/include/linux/page_compat.h
USER_H =
--- /dev/null
+#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
+#if defined(ZFS_ENUM_NODE_STAT_ITEM_NR_SLAB_RECLAIMABLE)
+#define nr_slab_reclaimable_pages() global_node_page_state(NR_SLAB_RECLAIMABLE)
+#else
+#define nr_slab_reclaimable_pages() global_zone_page_state(NR_SLAB_RECLAIMABLE)
+#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
+#if defined(ZFS_ENUM_NODE_STAT_ITEM_NR_SLAB_RECLAIMABLE)
+#define nr_slab_reclaimable_pages() global_node_page_state(NR_SLAB_RECLAIMABLE)
+#else
+#define nr_slab_reclaimable_pages() global_page_state(NR_SLAB_RECLAIMABLE)
+#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)
+#define nr_slab_reclaimable_pages() global_page_state(NR_SLAB_RECLAIMABLE)
+
+#endif /* ZFS_GLOBAL_ZONE_PAGE_STATE */
+
+#endif /* _ZFS_PAGE_COMPAT_H */
#include <sys/fs/swapnode.h>
#include <sys/zpl.h>
#include <linux/mm_compat.h>
+#include <linux/page_compat.h>
#endif
#include <sys/callb.h>
#include <sys/kstat.h>
si_meminfo(&si);
return (ptob(si.freeram - si.freehigh));
#else
-#ifdef ZFS_GLOBAL_NODE_PAGE_STATE
return (ptob(nr_free_pages() +
- global_node_page_state(NR_INACTIVE_FILE) +
- global_node_page_state(NR_INACTIVE_ANON) +
- global_node_page_state(NR_SLAB_RECLAIMABLE)));
-#else
- return (ptob(nr_free_pages() +
- global_page_state(NR_INACTIVE_FILE) +
- global_page_state(NR_INACTIVE_ANON) +
- global_page_state(NR_SLAB_RECLAIMABLE)));
-#endif /* ZFS_GLOBAL_NODE_PAGE_STATE */
+ nr_inactive_file_pages() +
+ nr_inactive_anon_pages() +
+ nr_slab_reclaimable_pages()));
+
#endif /* CONFIG_HIGHMEM */
#else
return (spa_get_random(arc_all_memory() * 20 / 100));
* Scale reported evictable memory in proportion to page cache, cap
* at specified min/max.
*/
-#ifdef ZFS_GLOBAL_NODE_PAGE_STATE
- uint64_t min = (ptob(global_node_page_state(NR_FILE_PAGES)) / 100) *
- zfs_arc_pc_percent;
-#else
- uint64_t min = (ptob(global_page_state(NR_FILE_PAGES)) / 100) *
- zfs_arc_pc_percent;
-#endif
+ uint64_t min = (ptob(nr_file_pages()) / 100) * zfs_arc_pc_percent;
min = MAX(arc_c_min, MIN(arc_c_max, min));
if (arc_dirty >= min)
pkgdatadir = $(datadir)/@PACKAGE@
dist_pkgdata_SCRIPTS = \
$(top_builddir)/scripts/common.sh \
+ $(top_srcdir)/scripts/enum-extract.pl \
$(top_srcdir)/scripts/zimport.sh \
$(top_srcdir)/scripts/zfs.sh \
$(top_srcdir)/scripts/zfs-tests.sh \
$(top_srcdir)/scripts/zpios-survey.sh \
$(top_srcdir)/scripts/smb.sh \
$(top_srcdir)/scripts/zfs-helpers.sh
+
--- /dev/null
+#!/usr/bin/perl -w
+
+my $usage = <<EOT;
+usage: config-enum enum [file ...]
+
+Returns the elements from an enum declaration.
+
+"Best effort": we're not building an entire C interpreter here!
+EOT
+
+use warnings;
+use strict;
+use Getopt::Std;
+
+my %opts;
+
+if (!getopts("", \%opts) || @ARGV < 1) {
+ print $usage;
+ exit 2;
+}
+
+my $enum = shift;
+
+my $in_enum = 0;
+
+while (<>) {
+ # comments
+ s/\/\*.*\*\///;
+ if (m/\/\*/) {
+ while ($_ .= <>) {
+ last if s/\/\*.*\*\///s;
+ }
+ }
+
+ # preprocessor stuff
+ next if /^#/;
+
+ # find our enum
+ $in_enum = 1 if s/^\s*enum\s+${enum}(?:\s|$)//;
+ next unless $in_enum;
+
+ # remove explicit values
+ s/\s*=[^,]+,/,/g;
+
+ # extract each identifier
+ while (m/\b([a-z_][a-z0-9_]*)\b/ig) {
+ print $1, "\n";
+ }
+
+ #
+ # don't exit: there may be multiple versions of the same enum, e.g.
+ # inside different #ifdef blocks. Let's explicitly return all of
+ # them and let external tooling deal with it.
+ #
+ $in_enum = 0 if m/}\s*;/;
+}
+
+exit 0;