Thread (6 messages) 6 messages, 5 authors, 2023-10-18

[PATCH] hv_balloon: Add module parameter to configure balloon floor value

From: Angelina Vu <hidden>
Date: 2023-10-10 22:48:12
Also in: lkml
Subsystem: hyper-v/azure core and drivers, the rest · Maintainers: "K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, Linus Torvalds

Currently, the balloon floor value is automatically computed, but may be
too small depending on app usage of memory. This patch adds a balloon_floor
value as a module parameter that can be used to manually configure the
balloon floor value.

Signed-off-by: Angelina Vu <redacted>
---
 drivers/hv/hv_balloon.c | 7 +++++++
 1 file changed, 7 insertions(+)
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index 64ac5bdee3a6..87b312f99b2e 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -1101,6 +1101,10 @@ static void process_info(struct hv_dynmem_device *dm, struct dm_info_msg *msg)
 	}
 }
 
+unsigned long balloon_floor;
+module_param(balloon_floor, ulong, 0644);
+MODULE_PARM_DESC(balloon_floor, "Memory level (in megabytes) that ballooning will not remove");
+
 static unsigned long compute_balloon_floor(void)
 {
 	unsigned long min_pages;
@@ -1117,6 +1121,9 @@ static unsigned long compute_balloon_floor(void)
 	 *    8192       744    (1/16)
 	 *   32768      1512	(1/32)
 	 */
+	if (balloon_floor)
+		return MB2PAGES(balloon_floor);
+
 	if (nr_pages < MB2PAGES(128))
 		min_pages = MB2PAGES(8) + (nr_pages >> 1);
 	else if (nr_pages < MB2PAGES(512))
-- 
2.34.1
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help