[dpdk-dev] [PATCH v2] eal/windows: detect insufficient privileges for hugepages

[Dmitry Kozlyuk]

AdjustTokenPrivileges() succeeds even if no requested privileges have
been granted; this behavior is documented. Check last error code in
addition to return value to detect such case.

Make error messages more specific and add troubleshooting hint.

Signed-off-by: Dmitry Kozlyuk <dmitry.kozl...@gmail.com>
---

v2:
    Improve error reporting (Tal Shnaiderman).

 lib/librte_eal/windows/eal_hugepages.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/librte_eal/windows/eal_hugepages.c 
b/lib/librte_eal/windows/eal_hugepages.c
index 5779cd325..7f8a7dfca 100644
--- a/lib/librte_eal/windows/eal_hugepages.c
+++ b/lib/librte_eal/windows/eal_hugepages.c
@@ -41,6 +41,10 @@ hugepage_claim_privilege(void)
                goto exit;
        }
 
+       /* AdjustTokenPrivileges() may succeed with ERROR_NOT_ALL_ASSIGNED. */
+       if (GetLastError() != ERROR_SUCCESS)
+               goto exit;
+
        ret = 0;
 
 exit:
@@ -98,12 +102,14 @@ int
 eal_hugepage_info_init(void)
 {
        if (hugepage_claim_privilege() < 0) {
-               RTE_LOG(ERR, EAL, "Cannot claim hugepage privilege\n");
+               RTE_LOG(ERR, EAL, "Cannot claim hugepage privilege\n"
+                       "Verify that large-page support privilege "
+                       "is assigned to the current user\n");
                return -1;
        }
 
        if (hugepage_info_init() < 0) {
-               RTE_LOG(ERR, EAL, "Cannot get hugepage information\n");
+               RTE_LOG(ERR, EAL, "Cannot discover available hugepages\n");
                return -1;
        }
 
-- 
2.25.4