Re: [libvirt] [PATCH 5/5] qemuBuildMemoryBackendProps: Get pagesize early

[Ján Tomko]

On Mon, Apr 01, 2019 at 04:04:37PM +0200, Michal Privoznik wrote:

https://bugzilla.redhat.com/show_bug.cgi?id=1693066

Up until memfd introduction (in 24b74d187ca) we did not need to
know @pagesize because qemuGetDomainHupageMemPath() could deal
with it being zero (value of zero means use the default hugetlbfs
mount). But since for memfd we are not passing a path to
hugetlbfs mount rather the page size value we need to know its
value upfront.

This phrasing makes it seem like getting the pagesize is being moved,

Signed-off-by: Michal Privoznik <mpriv...@redhat.com>
---
src/qemu/qemu_command.c                       | 14 +++++++
...memory-default-hugepage.x86_64-latest.args | 37 ++++++++++++++++
.../memfd-memory-default-hugepage.xml         | 42 +++++++++++++++++++
tests/qemuxml2argvtest.c                      |  1 +
.../memfd-memory-default-hugepage.xml         |  1 +
tests/qemuxml2xmltest.c                       |  3 ++
6 files changed, 98 insertions(+)

but there are no deletions. I'd expect that now it will no longer be
needed in qemuGetDomainHupageMemPath (sic).

create mode 100644 
tests/qemuxml2argvdata/memfd-memory-default-hugepage.x86_64-latest.args
create mode 100644 tests/qemuxml2argvdata/memfd-memory-default-hugepage.xml
create mode 120000 tests/qemuxml2xmloutdata/memfd-memory-default-hugepage.xml

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index f81d20e5f7..ba1b56c2da 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3547,6 +3547,20 @@ qemuBuildMemoryBackendProps(virJSONValuePtr 
*backendProps,
        pagesize = 0;
        needHugepage = false;
        useHugepage = false;
+    } else if (pagesize == 0) {
+        virHugeTLBFSPtr p;
+
+        if (!cfg->nhugetlbfs) {
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           "%s", _("hugetlbfs filesystem is not mounted "
+                                   "or disabled by administrator config"));
+            goto cleanup;
+        }
+
+        if (!(p = virFileGetDefaultHugepage(cfg->hugetlbfs, cfg->nhugetlbfs)))
+            p = &cfg->hugetlbfs[0];
+
+        pagesize = p->size;

Given how big and beautiful qemuBuildMemoryBackendProps has become,
this would look nicer in another wrapper.

With the corresponding deletions in qemuGetDomainHupageMemPath:
Reviewed-by: Ján Tomko <jto...@redhat.com>

Jano

signature.asc
Description: PGP signature

--
libvir-list mailing list
libvir-list@redhat.com
https://www.redhat.com/mailman/listinfo/libvir-list