[PATCH v3 2/3] dax: Add a wakeup mode parameter to put_unlocked_entry()

[Vivek Goyal]

As of now put_unlocked_entry() always wakes up next waiter. In next
patches we want to wake up all waiters at one callsite. Hence, add a
parameter to the function.

This patch does not introduce any change of behavior.

Suggested-by: Dan Williams <dan.j.willi...@intel.com>
Signed-off-by: Vivek Goyal <vgo...@redhat.com>
---
 fs/dax.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/fs/dax.c b/fs/dax.c
index 00978d0838b1..f19d76a6a493 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -275,11 +275,12 @@ static void wait_entry_unlocked(struct xa_state *xas, 
void *entry)
        finish_wait(wq, &ewait.wait);
 }
 
-static void put_unlocked_entry(struct xa_state *xas, void *entry)
+static void put_unlocked_entry(struct xa_state *xas, void *entry,
+                              enum dax_entry_wake_mode mode)
 {
        /* If we were the only waiter woken, wake the next one */
        if (entry && !dax_is_conflict(entry))
-               dax_wake_entry(xas, entry, WAKE_NEXT);
+               dax_wake_entry(xas, entry, mode);
 }
 
 /*
@@ -633,7 +634,7 @@ struct page *dax_layout_busy_page_range(struct 
address_space *mapping,
                        entry = get_unlocked_entry(&xas, 0);
                if (entry)
                        page = dax_busy_page(entry);
-               put_unlocked_entry(&xas, entry);
+               put_unlocked_entry(&xas, entry, WAKE_NEXT);
                if (page)
                        break;
                if (++scanned % XA_CHECK_SCHED)
@@ -675,7 +676,7 @@ static int __dax_invalidate_entry(struct address_space 
*mapping,
        mapping->nrexceptional--;
        ret = 1;
 out:
-       put_unlocked_entry(&xas, entry);
+       put_unlocked_entry(&xas, entry, WAKE_NEXT);
        xas_unlock_irq(&xas);
        return ret;
 }
@@ -954,7 +955,7 @@ static int dax_writeback_one(struct xa_state *xas, struct 
dax_device *dax_dev,
        return ret;
 
  put_unlocked:
-       put_unlocked_entry(xas, entry);
+       put_unlocked_entry(xas, entry, WAKE_NEXT);
        return ret;
 }
 
@@ -1695,7 +1696,7 @@ dax_insert_pfn_mkwrite(struct vm_fault *vmf, pfn_t pfn, 
unsigned int order)
        /* Did we race with someone splitting entry or so? */
        if (!entry || dax_is_conflict(entry) ||
            (order == 0 && !dax_is_pte_entry(entry))) {
-               put_unlocked_entry(&xas, entry);
+               put_unlocked_entry(&xas, entry, WAKE_NEXT);
                xas_unlock_irq(&xas);
                trace_dax_insert_pfn_mkwrite_no_entry(mapping->host, vmf,
                                                      VM_FAULT_NOPAGE);
-- 
2.25.4