kernel: move use_mm/unuse_mm to kthread.c

Patch series "improve use_mm / unuse_mm", v2.

This series improves the use_mm / unuse_mm interface by better documenting
the assumptions, and my taking the set_fs manipulations spread over the
callers into the core API.

This patch (of 3):

Use the proper API instead.

Link: http://lkml.kernel.org/r/20200404094101.672954-1-hch@lst.de

These helpers are only for use with kernel threads, and I will tie them
more into the kthread infrastructure going forward.  Also move the
prototypes to kthread.h - mmu_context.h was a little weird to start with
as it otherwise contains very low-level MM bits.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: http://lkml.kernel.org/r/20200404094101.672954-1-hch@lst.de
Link: http://lkml.kernel.org/r/20200416053158.586887-1-hch@lst.de
Link: http://lkml.kernel.org/r/20200404094101.672954-5-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Christoph Hellwig 2020-06-10 18:41:59 -07:00 committed by Linus Torvalds
parent 2c34f6f738
commit 9bf5b9eb23
18 changed files with 66 additions and 85 deletions

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@ -27,6 +27,7 @@
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/kthread.h>
#include <linux/workqueue.h>
#include <kgd_kfd_interface.h>
#include <drm/ttm/ttm_execbuf_util.h>

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@ -22,7 +22,6 @@
#include <linux/module.h>
#include <linux/fdtable.h>
#include <linux/uaccess.h>
#include <linux/mmu_context.h>
#include <linux/firmware.h>
#include "amdgpu.h"
#include "amdgpu_amdkfd.h"

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@ -19,7 +19,6 @@
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
#include <linux/mmu_context.h>
#include "amdgpu.h"
#include "amdgpu_amdkfd.h"
#include "gc/gc_10_1_0_offset.h"

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@ -20,8 +20,6 @@
* OTHER DEALINGS IN THE SOFTWARE.
*/
#include <linux/mmu_context.h>
#include "amdgpu.h"
#include "amdgpu_amdkfd.h"
#include "cikd.h"

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@ -20,8 +20,6 @@
* OTHER DEALINGS IN THE SOFTWARE.
*/
#include <linux/mmu_context.h>
#include "amdgpu.h"
#include "amdgpu_amdkfd.h"
#include "gfx_v8_0.h"

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@ -19,8 +19,6 @@
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
#include <linux/mmu_context.h>
#include "amdgpu.h"
#include "amdgpu_amdkfd.h"
#include "gc/gc_9_0_offset.h"

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@ -31,7 +31,7 @@
#include <linux/init.h>
#include <linux/device.h>
#include <linux/mm.h>
#include <linux/mmu_context.h>
#include <linux/kthread.h>
#include <linux/sched/mm.h>
#include <linux/types.h>
#include <linux/list.h>

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@ -32,7 +32,7 @@
#include <linux/usb/functionfs.h>
#include <linux/aio.h>
#include <linux/mmu_context.h>
#include <linux/kthread.h>
#include <linux/poll.h>
#include <linux/eventfd.h>

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@ -21,7 +21,7 @@
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/poll.h>
#include <linux/mmu_context.h>
#include <linux/kthread.h>
#include <linux/aio.h>
#include <linux/uio.h>
#include <linux/refcount.h>

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@ -14,7 +14,6 @@
#include <linux/vhost.h>
#include <linux/uio.h>
#include <linux/mm.h>
#include <linux/mmu_context.h>
#include <linux/miscdevice.h>
#include <linux/mutex.h>
#include <linux/poll.h>

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@ -27,7 +27,6 @@
#include <linux/file.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/mmu_context.h>
#include <linux/percpu.h>
#include <linux/slab.h>
#include <linux/timer.h>

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@ -10,7 +10,6 @@
#include <linux/errno.h>
#include <linux/sched/signal.h>
#include <linux/mm.h>
#include <linux/mmu_context.h>
#include <linux/sched/mm.h>
#include <linux/percpu.h>
#include <linux/slab.h>

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@ -55,7 +55,6 @@
#include <linux/fdtable.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/mmu_context.h>
#include <linux/percpu.h>
#include <linux/slab.h>
#include <linux/kthread.h>

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@ -5,6 +5,8 @@
#include <linux/err.h>
#include <linux/sched.h>
struct mm_struct;
__printf(4, 5)
struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
void *data,
@ -198,6 +200,9 @@ bool kthread_cancel_delayed_work_sync(struct kthread_delayed_work *work);
void kthread_destroy_worker(struct kthread_worker *worker);
void use_mm(struct mm_struct *mm);
void unuse_mm(struct mm_struct *mm);
struct cgroup_subsys_state;
#ifdef CONFIG_BLK_CGROUP

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@ -4,11 +4,6 @@
#include <asm/mmu_context.h>
struct mm_struct;
void use_mm(struct mm_struct *mm);
void unuse_mm(struct mm_struct *mm);
/* Architectures that care about IRQ state in switch_mm can override this. */
#ifndef switch_mm_irqs_off
# define switch_mm_irqs_off switch_mm

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@ -1,13 +1,17 @@
// SPDX-License-Identifier: GPL-2.0-only
/* Kernel thread helper functions.
* Copyright (C) 2004 IBM Corporation, Rusty Russell.
* Copyright (C) 2009 Red Hat, Inc.
*
* Creation is done via kthreadd, so that we get a clean environment
* even if we're invoked from userspace (think modprobe, hotplug cpu,
* etc.).
*/
#include <uapi/linux/sched/types.h>
#include <linux/mm.h>
#include <linux/mmu_context.h>
#include <linux/sched.h>
#include <linux/sched/mm.h>
#include <linux/sched/task.h>
#include <linux/kthread.h>
#include <linux/completion.h>
@ -25,6 +29,7 @@
#include <linux/numa.h>
#include <trace/events/sched.h>
static DEFINE_SPINLOCK(kthread_create_lock);
static LIST_HEAD(kthread_create_list);
struct task_struct *kthreadd_task;
@ -1203,6 +1208,57 @@ void kthread_destroy_worker(struct kthread_worker *worker)
}
EXPORT_SYMBOL(kthread_destroy_worker);
/*
* use_mm
* Makes the calling kernel thread take on the specified
* mm context.
* (Note: this routine is intended to be called only
* from a kernel thread context)
*/
void use_mm(struct mm_struct *mm)
{
struct mm_struct *active_mm;
struct task_struct *tsk = current;
task_lock(tsk);
active_mm = tsk->active_mm;
if (active_mm != mm) {
mmgrab(mm);
tsk->active_mm = mm;
}
tsk->mm = mm;
switch_mm(active_mm, mm, tsk);
task_unlock(tsk);
#ifdef finish_arch_post_lock_switch
finish_arch_post_lock_switch();
#endif
if (active_mm != mm)
mmdrop(active_mm);
}
EXPORT_SYMBOL_GPL(use_mm);
/*
* unuse_mm
* Reverses the effect of use_mm, i.e. releases the
* specified mm context which was earlier taken on
* by the calling kernel thread
* (Note: this routine is intended to be called only
* from a kernel thread context)
*/
void unuse_mm(struct mm_struct *mm)
{
struct task_struct *tsk = current;
task_lock(tsk);
sync_mm_rss(mm);
tsk->mm = NULL;
/* active_mm is still 'mm' */
enter_lazy_tlb(mm, tsk);
task_unlock(tsk);
}
EXPORT_SYMBOL_GPL(unuse_mm);
#ifdef CONFIG_BLK_CGROUP
/**
* kthread_associate_blkcg - associate blkcg to current kthread

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@ -41,7 +41,7 @@ obj-y := filemap.o mempool.o oom_kill.o fadvise.o \
maccess.o page-writeback.o \
readahead.o swap.o truncate.o vmscan.o shmem.o \
util.o mmzone.o vmstat.o backing-dev.o \
mm_init.o mmu_context.o percpu.o slab_common.o \
mm_init.o percpu.o slab_common.o \
compaction.o vmacache.o \
interval_tree.o list_lru.o workingset.o \
debug.o gup.o $(mmu-y)

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@ -1,64 +0,0 @@
/* Copyright (C) 2009 Red Hat, Inc.
*
* See ../COPYING for licensing terms.
*/
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/sched/mm.h>
#include <linux/sched/task.h>
#include <linux/mmu_context.h>
#include <linux/export.h>
#include <asm/mmu_context.h>
/*
* use_mm
* Makes the calling kernel thread take on the specified
* mm context.
* (Note: this routine is intended to be called only
* from a kernel thread context)
*/
void use_mm(struct mm_struct *mm)
{
struct mm_struct *active_mm;
struct task_struct *tsk = current;
task_lock(tsk);
active_mm = tsk->active_mm;
if (active_mm != mm) {
mmgrab(mm);
tsk->active_mm = mm;
}
tsk->mm = mm;
switch_mm(active_mm, mm, tsk);
task_unlock(tsk);
#ifdef finish_arch_post_lock_switch
finish_arch_post_lock_switch();
#endif
if (active_mm != mm)
mmdrop(active_mm);
}
EXPORT_SYMBOL_GPL(use_mm);
/*
* unuse_mm
* Reverses the effect of use_mm, i.e. releases the
* specified mm context which was earlier taken on
* by the calling kernel thread
* (Note: this routine is intended to be called only
* from a kernel thread context)
*/
void unuse_mm(struct mm_struct *mm)
{
struct task_struct *tsk = current;
task_lock(tsk);
sync_mm_rss(mm);
tsk->mm = NULL;
/* active_mm is still 'mm' */
enter_lazy_tlb(mm, tsk);
task_unlock(tsk);
}
EXPORT_SYMBOL_GPL(unuse_mm);