libxl_domain_setmaxmem() called during "xl mem-max" should update the
domain's memory/static-max Xenstore node, as otherwise "xl mem-set"
won't be able to set the memory size to the new maximum.
Adjust the related comments and documentation accordingly.
Signed-off-by: Juergen Gross <jgross@suse.com>
---
V2:
- adjust comments and docs (Anthony Perard)
V3:
- really adjust the docs (Anthony Perard)
---
docs/man/xl.1.pod.in | 11 +++++------
tools/libs/light/libxl_mem.c | 12 ++++++++++--
2 files changed, 15 insertions(+), 8 deletions(-)
diff --git a/docs/man/xl.1.pod.in b/docs/man/xl.1.pod.in
index e2176bd696..101e14241d 100644
--- a/docs/man/xl.1.pod.in
+++ b/docs/man/xl.1.pod.in
@@ -442,15 +442,14 @@ allocate.
The default unit is kiB. Add 't' for TiB, 'g' for GiB, 'm' for
MiB, 'k' for kiB, and 'b' for bytes (e.g., `2048m` for 2048 MiB).
-NB that users normally shouldn't need this command; B<xl mem-set> will
-set this as appropriate automatically.
-
I<mem> can't be set lower than the current memory target for
I<domain-id>. It is allowed to be higher than the configured maximum
memory size of the domain (B<maxmem> parameter in the domain's
-configuration). Note however that the initial B<maxmem> value is still
-used as an upper limit for B<xl mem-set>. Also note that calling B<xl
-mem-set> will reset this value.
+configuration).
+
+Setting the maximum memory size above the configured maximum memory size
+will require special guest support (memory hotplug) in order to be usable
+by the guest.
The domain will not receive any signal regarding the changed memory
limit.
diff --git a/tools/libs/light/libxl_mem.c b/tools/libs/light/libxl_mem.c
index c739d00f39..92ec09f4cf 100644
--- a/tools/libs/light/libxl_mem.c
+++ b/tools/libs/light/libxl_mem.c
@@ -20,8 +20,7 @@
/*
* Set the maximum memory size of the domain in the hypervisor. There is no
* change of the current memory size involved. The specified memory size can
- * even be above the configured maxmem size of the domain, but the related
- * Xenstore entry memory/static-max isn't modified!
+ * even be above the configured maxmem size of the domain.
*/
int libxl_domain_setmaxmem(libxl_ctx *ctx, uint32_t domid, uint64_t max_memkb)
{
@@ -82,6 +81,15 @@ int libxl_domain_setmaxmem(libxl_ctx *ctx, uint32_t domid, uint64_t max_memkb)
goto out;
}
+ rc = libxl__xs_printf(gc, XBT_NULL,
+ GCSPRINTF("%s/memory/static-max", dompath),
+ "%"PRIu64, max_memkb);
+ if (rc != 0) {
+ LOGED(ERROR, domid, "Couldn't set %s/memory/static-max, rc=%d\n",
+ dompath, rc);
+ goto out;
+ }
+
rc = 0;
out:
libxl_domain_config_dispose(&d_config);
--
2.34.1
domain's memory/static-max Xenstore node, as otherwise "xl mem-set"
won't be able to set the memory size to the new maximum.
Adjust the related comments and documentation accordingly.
Signed-off-by: Juergen Gross <jgross@suse.com>
---
V2:
- adjust comments and docs (Anthony Perard)
V3:
- really adjust the docs (Anthony Perard)
---
docs/man/xl.1.pod.in | 11 +++++------
tools/libs/light/libxl_mem.c | 12 ++++++++++--
2 files changed, 15 insertions(+), 8 deletions(-)
diff --git a/docs/man/xl.1.pod.in b/docs/man/xl.1.pod.in
index e2176bd696..101e14241d 100644
--- a/docs/man/xl.1.pod.in
+++ b/docs/man/xl.1.pod.in
@@ -442,15 +442,14 @@ allocate.
The default unit is kiB. Add 't' for TiB, 'g' for GiB, 'm' for
MiB, 'k' for kiB, and 'b' for bytes (e.g., `2048m` for 2048 MiB).
-NB that users normally shouldn't need this command; B<xl mem-set> will
-set this as appropriate automatically.
-
I<mem> can't be set lower than the current memory target for
I<domain-id>. It is allowed to be higher than the configured maximum
memory size of the domain (B<maxmem> parameter in the domain's
-configuration). Note however that the initial B<maxmem> value is still
-used as an upper limit for B<xl mem-set>. Also note that calling B<xl
-mem-set> will reset this value.
+configuration).
+
+Setting the maximum memory size above the configured maximum memory size
+will require special guest support (memory hotplug) in order to be usable
+by the guest.
The domain will not receive any signal regarding the changed memory
limit.
diff --git a/tools/libs/light/libxl_mem.c b/tools/libs/light/libxl_mem.c
index c739d00f39..92ec09f4cf 100644
--- a/tools/libs/light/libxl_mem.c
+++ b/tools/libs/light/libxl_mem.c
@@ -20,8 +20,7 @@
/*
* Set the maximum memory size of the domain in the hypervisor. There is no
* change of the current memory size involved. The specified memory size can
- * even be above the configured maxmem size of the domain, but the related
- * Xenstore entry memory/static-max isn't modified!
+ * even be above the configured maxmem size of the domain.
*/
int libxl_domain_setmaxmem(libxl_ctx *ctx, uint32_t domid, uint64_t max_memkb)
{
@@ -82,6 +81,15 @@ int libxl_domain_setmaxmem(libxl_ctx *ctx, uint32_t domid, uint64_t max_memkb)
goto out;
}
+ rc = libxl__xs_printf(gc, XBT_NULL,
+ GCSPRINTF("%s/memory/static-max", dompath),
+ "%"PRIu64, max_memkb);
+ if (rc != 0) {
+ LOGED(ERROR, domid, "Couldn't set %s/memory/static-max, rc=%d\n",
+ dompath, rc);
+ goto out;
+ }
+
rc = 0;
out:
libxl_domain_config_dispose(&d_config);
--
2.34.1