From: "Darrick J. Wong" <djwong@kernel.org> mainline inclusion from mainline-v6.10-rc2 commit 04d6dbb55301a29aeb9a197e6b0012cdc265f1e4 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IC8HLD CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- In commit 9adf40249e6c, we changed the behavior of the AIL thread to set its own task state to KILLABLE whenever the timeout value is nonzero. Unfortunately, this missed the fact that xfsaild_push will return 50ms (aka a longish sleep) when we reach the push target or the AIL becomes empty, so xfsaild goes to sleep for a long period of time in uninterruptible D state. This results in artificially high load averages because KILLABLE processes are UNINTERRUPTIBLE, which contributes to load average even though the AIL is asleep waiting for someone to interrupt it. It's not blocked on IOs or anything, but people scrap ps for processes that look like they're stuck in D state, so restore the previous threshold. Fixes: 9adf40249e6c ("xfs: AIL doesn't need manual pushing") Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org> Signed-off-by: Long Li <leo.lilong@huawei.com> --- fs/xfs/xfs_trans_ail.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c index a802353dcb2a..9ce88d96daa5 100644 --- a/fs/xfs/xfs_trans_ail.c +++ b/fs/xfs/xfs_trans_ail.c @@ -644,7 +644,12 @@ xfsaild( set_freezable(); while (1) { - if (tout) + /* + * Long waits of 50ms or more occur when we've run out of items + * to push, so we only want uninterruptible state if we're + * actually blocked on something. + */ + if (tout && tout <= 20) set_current_state(TASK_KILLABLE|TASK_FREEZABLE); else set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE); -- 2.39.2