diff options
| author | Jason Gunthorpe <jgg@mellanox.com> | 2019-08-06 20:15:42 -0300 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@mellanox.com> | 2019-08-20 09:35:02 -0300 |
| commit | c7d8b7824ff9de866a356e1892dbe9f191aa5d06 (patch) | |
| tree | a0e5a54cc6d3647bbcfcefb7aa72522a130e68d8 /kernel/fork.c | |
| parent | e4c057d02c9ef0b39bb88544b0c3c0a0a4d55ed6 (diff) | |
hmm: use mmu_notifier_get/put for 'struct hmm'
This is a significant simplification, it eliminates all the remaining
'hmm' stuff in mm_struct, eliminates krefing along the critical notifier
paths, and takes away all the ugly locking and abuse of page_table_lock.
mmu_notifier_get() provides the single struct hmm per struct mm which
eliminates mm->hmm.
It also directly guarantees that no mmu_notifier op callback is callable
while concurrent free is possible, this eliminates all the krefs inside
the mmu_notifier callbacks.
The remaining krefs in the range code were overly cautious, drivers are
already not permitted to free the mirror while a range exists.
Link: https://lore.kernel.org/r/20190806231548.25242-6-jgg@ziepe.ca
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'kernel/fork.c')
| -rw-r--r-- | kernel/fork.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index d8ae0f1b4148..bd4a0762f12f 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1007,7 +1007,6 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, mm_init_owner(mm, p); RCU_INIT_POINTER(mm->exe_file, NULL); mmu_notifier_mm_init(mm); - hmm_mm_init(mm); init_tlb_flush_pending(mm); #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS mm->pmd_huge_pte = NULL; |