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

From: Vivek Goyal
Date: Mon Apr 19 2021 - 17:39:06 EST


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.williams@xxxxxxxxx>
Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx>
---
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