Re: [PATCH v3] mm/page_owner: fix for deferred struct page init

[Qian Cai]

On 1/3/19 2:07 PM, Michal Hocko wrote> So can we make the revert with an
explanation that the patch was wrong?
> If we want to make hacks to catch more objects to be tracked then it
> would be great to have some numbers in hands.

Well, those numbers are subject to change depends on future start_kernel()
order. Right now, there are many functions could be caught earlier by page 
owner.

        kmemleak_init();
        debug_objects_mem_init();
        setup_per_cpu_pageset();
        numa_policy_init();
        acpi_early_init();
        if (late_time_init)
                late_time_init();
        sched_clock_init();
        calibrate_delay();
        pid_idr_init();
        anon_vma_init();
#ifdef CONFIG_X86
        if (efi_enabled(EFI_RUNTIME_SERVICES))
                efi_enter_virtual_mode();
#endif
        thread_stack_cache_init();
        cred_init();
        fork_init();
        proc_caches_init();
        uts_ns_init();
        buffer_init();
        key_init();
        security_init();
        dbg_late_init();
        vfs_caches_init();
        pagecache_init();
        signals_init();
        seq_file_init();
        proc_root_init();
        nsfs_init();
        cpuset_init();
        cgroup_init();
        taskstats_init_early();
        delayacct_init();

        check_bugs();

        acpi_subsystem_init();
        arch_post_acpi_subsys_init();
        sfi_init_late();

        if (efi_enabled(EFI_RUNTIME_SERVICES)) {
                efi_free_boot_services();

        rcu_scheduler_starting();
        /*
         * Wait until kthreadd is all set-up.
         */
        wait_for_completion(&kthreadd_done);

        /* Now the scheduler is fully set up and can do blocking allocations */
        gfp_allowed_mask = __GFP_BITS_MASK;

        /*
         * init can allocate pages on any node
         */
        set_mems_allowed(node_states[N_MEMORY]);

        cad_pid = task_pid(current);

        smp_prepare_cpus(setup_max_cpus);

        workqueue_init();

        init_mm_internals();

        do_pre_smp_initcalls();
        lockup_detector_init();

        smp_init();
        sched_init_smp();