diff options
| author | Olaf Hering <olaf@aepfle.de> | 2011-06-10 10:47:14 +0200 |
|---|---|---|
| committer | Olaf Hering <olaf@aepfle.de> | 2011-06-10 10:47:14 +0200 |
| commit | 7c4c4b9c333e48ad9f32e37cbaaf07f524e33973 (patch) | |
| tree | a17e59db3d5ca86738e8a49857fc9b970f8070dc /tools/xenpaging | |
| parent | d991b140458c33c2fc0137a43b406bb15c284558 (diff) | |
| download | xen-7c4c4b9c333e48ad9f32e37cbaaf07f524e33973.tar.gz xen-7c4c4b9c333e48ad9f32e37cbaaf07f524e33973.tar.bz2 xen-7c4c4b9c333e48ad9f32e37cbaaf07f524e33973.zip | |
xenpaging: correct dropping of pages to avoid full ring buffer
Doing a one-way channel from Xen to xenpaging is not possible with the
current ring buffer implementation. xenpaging uses the mem_event ring
buffer, which expects request/response pairs to make progress. The
previous patch, which tried to establish a one-way communication from
Xen to xenpaging, stalled the guest once the buffer was filled up with
requests. Correct page-dropping by taking the slow path and let
p2m_mem_paging_resume() consume the response from xenpaging. This makes
room for yet another request/response pair and avoids hanging guests.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Diffstat (limited to 'tools/xenpaging')
| -rw-r--r-- | tools/xenpaging/xenpaging.c | 22 |
1 files changed, 11 insertions, 11 deletions
diff --git a/tools/xenpaging/xenpaging.c b/tools/xenpaging/xenpaging.c index ee979e6f48..856efe7bc3 100644 --- a/tools/xenpaging/xenpaging.c +++ b/tools/xenpaging/xenpaging.c @@ -690,19 +690,19 @@ int main(int argc, char *argv[]) ERROR("Error populating page"); goto out; } + } - /* Prepare the response */ - rsp.gfn = req.gfn; - rsp.p2mt = req.p2mt; - rsp.vcpu_id = req.vcpu_id; - rsp.flags = req.flags; + /* Prepare the response */ + rsp.gfn = req.gfn; + rsp.p2mt = req.p2mt; + rsp.vcpu_id = req.vcpu_id; + rsp.flags = req.flags; - rc = xenpaging_resume_page(paging, &rsp, 1); - if ( rc != 0 ) - { - ERROR("Error resuming page"); - goto out; - } + rc = xenpaging_resume_page(paging, &rsp, 1); + if ( rc != 0 ) + { + ERROR("Error resuming page"); + goto out; } /* Evict a new page to replace the one we just paged in */ |