The quilt patch titled
Subject: mm/madvise: remove redundant mmap_lock operations from process_madvise()
has been removed from the -mm tree. Its filename was
mm-madvise-remove-redundant-mmap_lock-operations-from-process_madvise.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: SeongJae Park <sj@xxxxxxxxxx>
Subject: mm/madvise: remove redundant mmap_lock operations from process_madvise()
Date: Wed, 5 Feb 2025 22:15:17 -0800
Optimize redundant mmap lock operations from process_madvise() by directly
doing the mmap locking first, and then the remaining works for all ranges
in the loop.
[akpm@xxxxxxxxxxxxxxxxxxxx: update comment, per Lorenzo]
Link: https://lkml.kernel.org/r/20250206061517.2958-5-sj@xxxxxxxxxx
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
Reviewed-by: Shakeel Butt <shakeel.butt@xxxxxxxxx>
Reviewed-by: Liam R. Howlett <howlett@xxxxxxxxx>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/madvise.c | 28 +++++++++++++++++++++++++---
1 file changed, 25 insertions(+), 3 deletions(-)
--- a/mm/madvise.c~mm-madvise-remove-redundant-mmap_lock-operations-from-process_madvise
+++ a/mm/madvise.c
@@ -1778,16 +1778,33 @@ static ssize_t vector_madvise(struct mm_
total_len = iov_iter_count(iter);
+ ret = madvise_lock(mm, behavior);
+ if (ret)
+ return ret;
+
while (iov_iter_count(iter)) {
- ret = do_madvise(mm, (unsigned long)iter_iov_addr(iter),
- iter_iov_len(iter), behavior);
+ unsigned long start = (unsigned long)iter_iov_addr(iter);
+ size_t len_in = iter_iov_len(iter);
+ size_t len;
+
+ if (!is_valid_madvise(start, len_in, behavior)) {
+ ret = -EINVAL;
+ break;
+ }
+
+ len = PAGE_ALIGN(len_in);
+ if (start + len == start)
+ ret = 0;
+ else
+ ret = madvise_do_behavior(mm, start, len_in, len,
+ behavior);
/*
* An madvise operation is attempting to restart the syscall,
* but we cannot proceed as it would not be correct to repeat
* the operation in aggregate, and would be surprising to the
* user.
*
- * As we have already dropped locks, it is safe to just loop and
+ * We drop and reacquire locks so it is safe to just loop and
* try again. We check for fatal signals in case we need exit
* early anyway.
*/
@@ -1796,12 +1813,17 @@ static ssize_t vector_madvise(struct mm_
ret = -EINTR;
break;
}
+
+ /* Drop and reacquire lock to unwind race. */
+ madvise_unlock(mm, behavior);
+ madvise_lock(mm, behavior);
continue;
}
if (ret < 0)
break;
iov_iter_advance(iter, iter_iov_len(iter));
}
+ madvise_unlock(mm, behavior);
ret = (total_len - iov_iter_count(iter)) ? : ret;
_
Patches currently in -mm which might be from sj@xxxxxxxxxx are
mm-damon-sysfs-schemes-let-damon_sysfs_scheme_set_filters-be-used-for-different-named-directories.patch
mm-damon-sysfs-schemes-implement-core_filters-and-ops_filters-directories.patch
mm-damon-sysfs-schemes-commit-filters-in-coreops_filters-directories.patch
mm-damon-core-expose-damos_filter_for_ops-to-damon-kernel-api-callers.patch
mm-damon-sysfs-schemes-record-filters-of-which-layer-should-be-added-to-the-given-filters-directory.patch
mm-damon-sysfs-schemes-return-error-when-for-attempts-to-install-filters-on-wrong-sysfs-directory.patch
docs-abi-damon-document-coreops_filters-directories.patch
docs-admin-guide-mm-damon-usage-update-for-coreops_filters-directories.patch
mm-damon-sysfs-validate-user-inputs-from-damon_sysfs_commit_input.patch
mm-damon-core-invoke-kdamond_call-after-merging-is-done-if-possible.patch
mm-damon-core-make-damon_set_attrs-be-safe-to-be-called-from-damon_call.patch
mm-damon-sysfs-handle-commit-command-using-damon_call.patch
mm-damon-sysfs-remove-damon_sysfs_cmd_request-code-from-damon_sysfs_handle_cmd.patch
mm-damon-sysfs-remove-damon_sysfs_cmd_request_callback-and-its-callers.patch
mm-damon-sysfs-remove-damon_sysfs_cmd_request-and-its-readers.patch
mm-damon-sysfs-schemes-remove-obsolete-comment-for-damon_sysfs_schemes_clear_regions.patch
mm-damon-remove-damon_callback-private.patch
mm-damon-remove-before_start-of-damon_callback.patch
mm-damon-remove-damon_callback-after_sampling.patch
mm-damon-remove-damon_callback-before_damos_apply.patch
mm-damon-remove-damon_operations-reset_aggregated.patch
mm-damon-sysfs-schemes-avoid-wformat-security-warning-on-damon_sysfs_access_pattern_add_range_dir.patch
mm-madvise-use-is_memory_failure-from-madvise_do_behavior.patch
mm-madvise-split-out-populate-behavior-check-logic.patch
mm-madvise-deduplicate-madvise_do_behavior-skip-case-handlings.patch
mm-madvise-remove-len-parameter-of-madvise_do_behavior.patch
