From 03b84099d9c4d3f1b4d1b123abc967e81f6d15db Mon Sep 17 00:00:00 2001 From: Rob Norris Date: Sun, 17 Dec 2023 00:36:21 +1100 Subject: linux 6.7 compat: rework shrinker setup for heap allocations 6.7 changes the shrinker API such that shrinkers must be allocated dynamically by the kernel. To accomodate this, this commit reworks spl_register_shrinker() to do something similar against earlier kernels. Signed-off-by: Rob Norris Sponsored-by: https://github.com/sponsors/robn --- module/Kbuild.in | 1 + module/os/linux/spl/spl-shrinker.c | 115 +++++++++++++++++++++++++++++++++++++ module/os/linux/zfs/arc_os.c | 11 ++-- 3 files changed, 123 insertions(+), 4 deletions(-) create mode 100644 module/os/linux/spl/spl-shrinker.c (limited to 'module') diff --git a/module/Kbuild.in b/module/Kbuild.in index b9c284a24..f1a145779 100644 --- a/module/Kbuild.in +++ b/module/Kbuild.in @@ -79,6 +79,7 @@ SPL_OBJS := \ spl-kstat.o \ spl-proc.o \ spl-procfs-list.o \ + spl-shrinker.o \ spl-taskq.o \ spl-thread.o \ spl-trace.o \ diff --git a/module/os/linux/spl/spl-shrinker.c b/module/os/linux/spl/spl-shrinker.c new file mode 100644 index 000000000..d5c8da471 --- /dev/null +++ b/module/os/linux/spl/spl-shrinker.c @@ -0,0 +1,115 @@ +/* + * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC. + * Copyright (C) 2007 The Regents of the University of California. + * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). + * Written by Brian Behlendorf . + * UCRL-CODE-235197 + * + * This file is part of the SPL, Solaris Porting Layer. + * + * The SPL is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * The SPL is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + * + * You should have received a copy of the GNU General Public License along + * with the SPL. If not, see . + * + * Solaris Porting Layer (SPL) Shrinker Implementation. + */ + +#include +#include + +#ifdef HAVE_SINGLE_SHRINKER_CALLBACK +/* 3.0-3.11: single shrink() callback, which we wrap to carry both functions */ +struct spl_shrinker_wrap { + struct shrinker shrinker; + spl_shrinker_cb countfunc; + spl_shrinker_cb scanfunc; +}; + +static int +spl_shrinker_single_cb(struct shrinker *shrinker, struct shrink_control *sc) +{ + struct spl_shrinker_wrap *sw = (struct spl_shrinker_wrap *)shrinker; + + if (sc->nr_to_scan != 0) + (void) sw->scanfunc(&sw->shrinker, sc); + return (sw->countfunc(&sw->shrinker, sc)); +} +#endif + +struct shrinker * +spl_register_shrinker(const char *name, spl_shrinker_cb countfunc, + spl_shrinker_cb scanfunc, int seek_cost) +{ + struct shrinker *shrinker; + + /* allocate shrinker */ +#if defined(HAVE_SHRINKER_REGISTER) + /* 6.7: kernel will allocate the shrinker for us */ + shrinker = shrinker_alloc(0, name); +#elif defined(HAVE_SPLIT_SHRINKER_CALLBACK) + /* 3.12-6.6: we allocate the shrinker */ + shrinker = kmem_zalloc(sizeof (struct shrinker), KM_SLEEP); +#elif defined(HAVE_SINGLE_SHRINKER_CALLBACK) + /* 3.0-3.11: allocate a wrapper */ + struct spl_shrinker_wrap *sw = + kmem_zalloc(sizeof (struct spl_shrinker_wrap), KM_SLEEP); + shrinker = &sw->shrinker; +#else + /* 2.x-2.6.22, or a newer shrinker API has been introduced. */ +#error "Unknown shrinker API" +#endif + + if (shrinker == NULL) + return (NULL); + + /* set callbacks */ +#ifdef HAVE_SINGLE_SHRINKER_CALLBACK + sw->countfunc = countfunc; + sw->scanfunc = scanfunc; + shrinker->shrink = spl_shrinker_single_cb; +#else + shrinker->count_objects = countfunc; + shrinker->scan_objects = scanfunc; +#endif + + /* set params */ + shrinker->seeks = seek_cost; + + /* register with kernel */ +#if defined(HAVE_SHRINKER_REGISTER) + shrinker_register(shrinker); +#elif defined(HAVE_REGISTER_SHRINKER_VARARG) + register_shrinker(shrinker, name); +#else + register_shrinker(shrinker); +#endif + + return (shrinker); +} +EXPORT_SYMBOL(spl_register_shrinker); + +void +spl_unregister_shrinker(struct shrinker *shrinker) +{ +#if defined(HAVE_SHRINKER_REGISTER) + shrinker_free(shrinker); +#elif defined(HAVE_SPLIT_SHRINKER_CALLBACK) + unregister_shrinker(shrinker); + kmem_free(shrinker, sizeof (struct shrinker)); +#elif defined(HAVE_SINGLE_SHRINKER_CALLBACK) + unregister_shrinker(shrinker); + kmem_free(shrinker, sizeof (struct spl_shrinker_wrap)); +#else +#error "Unknown shrinker API" +#endif +} +EXPORT_SYMBOL(spl_unregister_shrinker); diff --git a/module/os/linux/zfs/arc_os.c b/module/os/linux/zfs/arc_os.c index 43ed087e2..1fa9f3eb3 100644 --- a/module/os/linux/zfs/arc_os.c +++ b/module/os/linux/zfs/arc_os.c @@ -247,8 +247,7 @@ arc_shrinker_scan(struct shrinker *shrink, struct shrink_control *sc) return (sc->nr_to_scan); } -SPL_SHRINKER_DECLARE(arc_shrinker, - arc_shrinker_count, arc_shrinker_scan, DEFAULT_SEEKS); +static struct shrinker *arc_shrinker = NULL; int arc_memory_throttle(spa_t *spa, uint64_t reserve, uint64_t txg) @@ -351,14 +350,18 @@ arc_lowmem_init(void) * reclaim from the arc. This is done to prevent kswapd from * swapping out pages when it is preferable to shrink the arc. */ - spl_register_shrinker(&arc_shrinker); + arc_shrinker = spl_register_shrinker("zfs-arc-shrinker", + arc_shrinker_count, arc_shrinker_scan, DEFAULT_SEEKS); + VERIFY(arc_shrinker); + arc_set_sys_free(allmem); } void arc_lowmem_fini(void) { - spl_unregister_shrinker(&arc_shrinker); + spl_unregister_shrinker(arc_shrinker); + arc_shrinker = NULL; } int -- cgit v1.2.3