forked from luck/tmp_suning_uos_patched
f1f1007644
Apart from adding the helper function itself, the rest of the kernel is converted mechanically using: git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)->mm_count);/mmgrab\(\1\);/' git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)\.mm_count);/mmgrab\(\&\1\);/' This is needed for a later patch that hooks into the helper, but might be a worthwhile cleanup on its own. (Michal Hocko provided most of the kerneldoc comment.) Link: http://lkml.kernel.org/r/20161218123229.22952-1-vegard.nossum@oracle.com Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
63 lines
1.3 KiB
C
63 lines
1.3 KiB
C
/* Copyright (C) 2009 Red Hat, Inc.
|
|
*
|
|
* See ../COPYING for licensing terms.
|
|
*/
|
|
|
|
#include <linux/mm.h>
|
|
#include <linux/sched.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);
|