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From:   Vivek Goyal <vgoyal@redhat.com>
To:     linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-nvdimm@lists.01.org, virtio-fs@redhat.com,
        dan.j.williams@intel.com
Cc:     vgoyal@redhat.com, willy@infradead.org, jack@suse.cz,
        groug@kaod.org
Subject: [PATCH v6 2/3] dax: Add a wakeup mode parameter to put_unlocked_entry()
Date:   Wed, 28 Apr 2021 15:03:13 -0400
Message-Id: <20210428190314.1865312-3-vgoyal@redhat.com>
In-Reply-To: <20210428190314.1865312-1-vgoyal@redhat.com>
References: <20210428190314.1865312-1-vgoyal@redhat.com>
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Precedence: bulk

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.

Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 fs/dax.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/fs/dax.c b/fs/dax.c
index 5ecee51c44ee..56eb1c759ca5 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -275,11 +275,11 @@ 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_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 +633,7 @@ 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 +675,7 @@ 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 +954,7 @@ 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 +1695,7 @@ 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