iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mempolicy: mpol_shared_policy_init() without pseudo-vma

Browse Source 
mpol_shared_policy_init() does not need to use a pseudo-vma: it can use
sp_alloc() and sp_insert() directly, since the object's shared policy tree
is empty and inaccessible (needing no lock) at get_inode() time.

Link: https://lkml.kernel.org/r/3bef62d8-ae78-4c2-533-56a44ae425c@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tejun heo <tj@kernel.org>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Hugh Dickins 2023-10-03 02:22:59 -07:00 committed by Andrew Morton
parent 93397c3b76
commit 35ec8fa020
1 changed files with 14 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
mm/mempolicy.c
View File

@ -2736,30 +2736,30 @@ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
rwlock_init(&sp->lock);
if (mpol) {
struct vm_area_struct pvma;
struct mempolicy *new;
struct sp_node *sn;
struct mempolicy *npol;
NODEMASK_SCRATCH(scratch);
if (!scratch)
goto put_mpol;
/* contextualize the tmpfs mount point mempolicy */
new = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask);
if (IS_ERR(new))
/* contextualize the tmpfs mount point mempolicy to this file */
npol = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask);
if (IS_ERR(npol))
goto free_scratch; /* no valid nodemask intersection */
task_lock(current);
ret = mpol_set_nodemask(new, &mpol->w.user_nodemask, scratch);
ret = mpol_set_nodemask(npol, &mpol->w.user_nodemask, scratch);
task_unlock(current);
if (ret)
goto put_new;
goto put_npol;
/* Create pseudo-vma that contains just the policy */
vma_init(&pvma, NULL);
pvma.vm_end = TASK_SIZE; /* policy covers entire file */
mpol_set_shared_policy(sp, &pvma, new); /* adds ref */
put_new:
mpol_put(new); /* drop initial ref */
/* alloc node covering entire file; adds ref to file's npol */
sn = sp_alloc(0, MAX_LFS_FILESIZE >> PAGE_SHIFT, npol);
if (sn)
sp_insert(sp, sn);
put_npol:
mpol_put(npol); /* drop initial ref on file's npol */
free_scratch:
NODEMASK_SCRATCH_FREE(scratch);
put_mpol: