Re: [libvirt] [PATCH 2/2] util: Produce friendlier error message to user
On 10/02/2015 11:49 PM, John Ferlan wrote:
On 09/30/2015 12:01 AM, Luyao Huang wrote:
> Commit 1c24cfe9 fix the problem in virNumaSetPagePoolSize,
> this patch just like it and fix the issue in another function.
>
> when user use freepages and specify a invalid node or page size,
> will get error like this:
>
> # virsh freepages 0 1
> error: Failed to open file
'/sys/devices/system/node/node0/hugepages/hugepages-1kB/free_hugepages': No such
file or directory
>
> Add two checks to catch this and therefore produce much more
> friendlier error messages.
>
> Signed-off-by: Luyao Huang <lhuang(a)redhat.com>
> ---
> src/util/virnuma.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
Perhaps the more entertaining part of this patch is/was it possible to
use "freepages 0 0"? Before patch 1, before patch 2, after patch 2.
Patch 1 + 2 can improve the error when use "freepages 0 0"
Based on the answer to the question below, I can adjust the commit
message (and code if necessary) a bit in order to remove the really long
line and make it flow better.
Thanks a lot for your help, i am not sure about if we need rework this
code or add a patch 3 to improve the error message, please help to check
the reply i will give in another mail.
> diff --git a/src/util/virnuma.c b/src/util/virnuma.c
> index 8577bd8..c8beade 100644
> --- a/src/util/virnuma.c
> +++ b/src/util/virnuma.c
> @@ -560,6 +560,12 @@ virNumaGetHugePageInfo(int node,
> page_size, "nr_hugepages") <
0)
> goto cleanup;
>
> + if (!virFileExists(path)) {
> + virReportError(VIR_ERR_OPERATION_FAILED, "%s",
> + _("page size or NUMA node not available"));
> + goto cleanup;
> + }
> +
Why is there no "if (node != -1 && !virNumaNodeIsAvailable(node)) {"
check prior to the virNumaGetHugePageInfoPath call?
<same for next change too>
Hmm... i think this check is enough since the output error is "page size
or NUMA node not available", the output message have already include the
case which pass a invalid NUMA node.
I thought that add a check like "if (node != -1 &&
!virNumaNodeIsAvailable(node)) {" just output a different error in this
place, however this (invalid nodeset) will be caught more early in
another place (in nodeGetFreePages function):
if (startCell > lastCell) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("start cell %d out of range (0-%d)"),
startCell, lastCell);
goto cleanup;
}
I noticed another reply from you to this mail, and think we can make the
error more clearly as your said in another reply. I will continue to
reply in another mail.
Thanks a lot for your review and help !
John
Luyao
> if (virFileReadAll(path, 1024, &buf) < 0)
> goto cleanup;
>
> @@ -579,6 +585,12 @@ virNumaGetHugePageInfo(int node,
> page_size, "free_hugepages") <
0)
> goto cleanup;
>
> + if (!virFileExists(path)) {
> + virReportError(VIR_ERR_OPERATION_FAILED, "%s",
> + _("page size or NUMA node not available"));
> + goto cleanup;
> + }
> +
> if (virFileReadAll(path, 1024, &buf) < 0)
> goto cleanup;
>
>