mm/damon/dbgfs: use damon_select_ops() instead of damon_{v,p}a_set_operations()

This commit makes DAMON debugfs interface to select the registered
monitoring operations for the physical address space or virtual address
spaces depending on user requests instead of setting it on its own.  Note
that DAMON debugfs interface is still dependent to DAMON_VADDR with this
change, because it is also using its symbol, 'damon_va_target_valid'.

Link: https://lkml.kernel.org/r/20220215184603.1479-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c
index 719278a8cc5ebe249dbe01a43dd6bcd3239e6d95..8bf9e38b60f47e377a015c437aa45da8cdd769b6 100644 (file)
--- a/mm/damon/dbgfs.c
+++ b/mm/damon/dbgfs.c
@@ -474,12 +474,18 @@ static ssize_t dbgfs_target_ids_write(struct file *file,
 
        /* remove previously set targets */
        dbgfs_set_targets(ctx, 0, NULL);
+       if (!nr_targets) {
+               ret = count;
+               goto unlock_out;
+       }
 
        /* Configure the context for the address space type */
        if (id_is_pid)
-               damon_va_set_operations(ctx);
+               ret = damon_select_ops(ctx, DAMON_OPS_VADDR);
        else
-               damon_pa_set_operations(ctx);
+               ret = damon_select_ops(ctx, DAMON_OPS_PADDR);
+       if (ret)
+               goto unlock_out;
 
        ret = dbgfs_set_targets(ctx, nr_targets, target_pids);
        if (!ret)
@@ -735,7 +741,11 @@ static struct damon_ctx *dbgfs_new_ctx(void)
        if (!ctx)
                return NULL;
 
-       damon_va_set_operations(ctx);
+       if (damon_select_ops(ctx, DAMON_OPS_VADDR) && damon_select_ops(ctx,
+                               DAMON_OPS_PADDR)) {
+               damon_destroy_ctx(ctx);
+               return NULL;
+       }
        ctx->callback.before_terminate = dbgfs_before_terminate;
        return ctx;
 }