mm/damon/core: set damon_ctx->walk_control_obsolete in damon_new_ctx()

damos_walk() should be called for a damon_ctx context that has
successfully started at least once.  That's because
damon_ctx->walk_control_obsolete is initialized when kdamond starts.  If
the rule is violated, an indefinite wait can happen.  There is no
existing violation of the rule.

damon_call() had a similar rule, and it turned out keeping the rule is
not easy for damon_call()'s case.  Hence, commit 8023b5f47e09
("mm/damon/core: set ctx->call_controls_obsolete in damon_new_ctx()")
added the initialization in damon_new_ctx() and removed the rule.

Keeping the rule for damos_walk() is relatively easier.  But having
slightly different rules for similar functions could be confusing.
Sashiko, for example, repeatedly asked questions about this.  Do the
initialization of walk_control_obsolete in damon_new_ctx() for
consistency.

Link: https://lore.kernel.org/20260917142210.90829-5-sj@kernel.org
Link: https://lore.kernel.org/20260915011614.102342-1-sj@kernel.org [1]
Signed-off-by: SJ Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Asier Gutierrez <gutierrez.asier@huawei-partners.com>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@davidgow.net>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>

0 files changed, 0 insertions, 0 deletions