The patch titled
mempolicy: document {set|get}_policy() vm_ops APIs
has been added to the -mm tree. Its filename is
mempolicy-document-setget_policy-vm_ops-apis.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: mempolicy: document {set|get}_policy() vm_ops APIs
From: Lee Schermerhorn <lee.schermerhorn@xxxxxx>
Document mempolicy return value reference semantics assumed by the rest of the
mempolicy code for the set_ and get_policy vm_ops in <linux/mm.h>--where the
prototypes are defined--to inform any future mempolicy vm_op writers what the
rest of the subsystem expects of them.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@xxxxxx>
Cc: Christoph Lameter <clameter@xxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Mel Gorman <mel@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/mm.h | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff -puN include/linux/mm.h~mempolicy-document-setget_policy-vm_ops-apis include/linux/mm.h
--- a/include/linux/mm.h~mempolicy-document-setget_policy-vm_ops-apis
+++ a/include/linux/mm.h
@@ -172,7 +172,25 @@ struct vm_operations_struct {
* writable, if an error is returned it will cause a SIGBUS */
int (*page_mkwrite)(struct vm_area_struct *vma, struct page *page);
#ifdef CONFIG_NUMA
+ /*
+ * set_policy() op must add a reference to any non-NULL @new mempolicy
+ * to hold the policy upon return. Caller should pass NULL @new to
+ * remove a policy and fall back to surrounding context--i.e. do not
+ * install a MPOL_DEFAULT policy, nor the task or system default
+ * mempolicy.
+ */
int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
+
+ /*
+ * get_policy() op must add reference [mpol_get()] to any policy at
+ * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure
+ * in mm/mempolicy.c will do this automatically.
+ * get_policy() must NOT add a ref if the policy at (vma,addr) is not
+ * marked as MPOL_SHARED. vma policies are protected by the mmap_sem.
+ * If no [shared/vma] mempolicy exists at the addr, get_policy() op
+ * must return NULL--i.e., do not "fallback" to task or system default
+ * policy.
+ */
struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
unsigned long addr);
int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from,
_
Patches currently in -mm which might be from lee.schermerhorn@xxxxxx are
mm-use-zonelists-instead-of-zones-when-direct-reclaiming-pages.patch
mm-introduce-node_zonelist-for-accessing-the-zonelist-for-a-gfp-mask.patch
mm-remember-what-the-preferred-zone-is-for-zone_statistics.patch
mm-use-two-zonelist-that-are-filtered-by-gfp-mask.patch
mm-have-zonelist-contains-structs-with-both-a-zone-pointer-and-zone_idx.patch
mm-have-zonelist-contains-structs-with-both-a-zone-pointer-and-zone_idx-fix-memcg-ooms.patch
mm-have-zonelist-contains-structs-with-both-a-zone-pointer-and-zone_idx-just-return-do_try_to_free_pages.patch
mm-have-zonelist-contains-structs-with-both-a-zone-pointer-and-zone_idx-just-return-do_try_to_free_pages-do_try_to_free_pages-gfp_mask-redundant.patch
mm-filter-based-on-a-nodemask-as-well-as-a-gfp_mask.patch
mm-filter-based-on-a-nodemask-as-well-as-a-gfp_mask-doc-fixes.patch
mm-filter-based-on-a-nodemask-as-well-as-a-gfp_mask-make-dequeue_huge_page_vma-obey-mpol_bind-nodemask.patch
mm-filter-based-on-a-nodemask-as-well-as-a-gfp_mask-make-dequeue_huge_page_vma-obey-mpol_bind-nodemask-rework.patch
mm-filter-based-on-a-nodemask-as-well-as-a-gfp_mask-deporkify.patch
mempolicy-add-bitmap_onto-and-bitmap_fold-operations.patch
mempolicy-create-mempolicy_operations-structure-fix.patch
mempolicy-disallow-static-or-relative-flags-for-local-preferred-mode.patch
mempolicy-fix-parsing-of-tmpfs-mpol-mount-option.patch
mempolicy-rename-mpol_free-to-mpol_put.patch
mempolicy-rename-mpol_copy-to-mpol_dup.patch
mempolicy-write-lock-mmap_sem-while-changing-task-mempolicy.patch
mempolicy-fixup-fallback-for-default-shmem-policy.patch
mempolicy-rename-struct-mempolicy-policy-member-to-mode.patch
mempolicy-mark-shared-policies-for-unref.patch
mempolicy-document-setget_policy-vm_ops-apis.patch
mempolicy-rework-mempolicy-reference-counting.patch
mempolicy-use-mpol_preferred-for-system-wide-default-policy.patch
mempolicy-mpol_preferred-cleanups-for-local-allocation.patch
mempolicy-use-mpol_f_local-to-indicate-preferred-local-policy.patch
mempolicy-clean-up-mpol-to-str-mempolicy-formatting.patch
mempolicy-rework-shmem-mpol-parsing-and-display.patch
mempolicy-support-mpol=local-tmpfs-mount-option.patch
mempolicy-use-struct-mempolicy-pointer-in-shmem_sb_info.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
