[LU-6881] sub_trans_commit_cb() is racy

• Type: Bug
• Resolution: Fixed
• Priority: Critical
• Fix Version/s: Lustre 2.8.0
• Severity: 3
• Assignee: Di Wang
• Reporter: Niu Yawei (Inactive)

Description

sub_trans_commit_cb() can be called by in parallel, so all_committed could be set to false even if all sub transactions are committed.

static void sub_trans_commit_cb(struct lu_env *env,
                                struct thandle *sub_th,
                                struct dt_txn_commit_cb *cb, int err)
{
        struct sub_thandle      *st;
        struct top_multiple_thandle *tmt = cb->dcb_data;
        bool                    all_committed = true;
        ENTRY;

        /* Check if all sub thandles are committed */
        list_for_each_entry(st, &tmt->tmt_sub_thandle_list, st_sub_list) {
                if (st->st_sub_th == sub_th) {
                        st->st_committed = 1;
                        st->st_result = err;
                }
                if (!st->st_committed)
                        all_committed = false;
        }

        if (tmt->tmt_result == 0)
                tmt->tmt_result = err;

        if (all_committed)
                top_trans_committed_cb(tmt);

        top_multiple_thandle_dump(tmt, D_INFO);
        top_multiple_thandle_put(tmt);
        RETURN_EXIT;
}