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page_pool: store detach_time as ktime_t to avoid false-negatives

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While testing other changes in vng I noticed that
nl_netdev.page_pool_check flakes. This never happens in real CI.

Turns out vng may boot and get to that test in less than a second.
page_pool_detached() records the detach time in seconds, so if
vng is fast enough detach time is set to 0. Other code treats
0 as "not detached". detach_time is only used to report the state
to the user, so it's not a huge deal in practice but let's fix it.
Store the raw ktime_t (nanoseconds) instead. A nanosecond value
of 0 is practically impossible.

Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Fixes: 69cb4952b6 ("net: page_pool: report when page pool was destroyed")
Link: https://patch.msgid.link/20260310003907.3540019-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Jakub Kicinski
2026-03-09 17:39:07 -07:00
parent 881a0263d5
commit 28b225282d
2 changed files with 3 additions and 3 deletions
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2
include/net/page_pool/types.h
View File

@@ -247,7 +247,7 @@ struct page_pool {
/* User-facing fields, protected by page_pools_lock */
struct {
struct hlist_node list;
u64 detach_time;
ktime_t detach_time;
u32 id;
} user;
};

4
net/core/page_pool_user.c
View File

@@ -245,7 +245,7 @@ page_pool_nl_fill(struct sk_buff *rsp, const struct page_pool *pool,
goto err_cancel;
if (pool->user.detach_time &&
nla_put_uint(rsp, NETDEV_A_PAGE_POOL_DETACH_TIME,
pool->user.detach_time))
ktime_divns(pool->user.detach_time, NSEC_PER_SEC)))
goto err_cancel;
if (pool->mp_ops && pool->mp_ops->nl_fill(pool->mp_priv, rsp, NULL))
@@ -337,7 +337,7 @@ err_unlock:
void page_pool_detached(struct page_pool *pool)
{
mutex_lock(&page_pools_lock);
pool->user.detach_time = ktime_get_boottime_seconds();
pool->user.detach_time = ktime_get_boottime();
netdev_nl_page_pool_event(pool, NETDEV_CMD_PAGE_POOL_CHANGE_NTF);
mutex_unlock(&page_pools_lock);
}