Re: [PATCH 1/3] mm: page_alloc: Reduce object size by neatening printks

[Sergey Senozhatsky]

On (03/15/17 18:43), Joe Perches wrote:
[..]
> -	printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
> -		" active_file:%lu inactive_file:%lu isolated_file:%lu\n"
> -		" unevictable:%lu dirty:%lu writeback:%lu unstable:%lu\n"
> -		" slab_reclaimable:%lu slab_unreclaimable:%lu\n"
> -		" mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n"
> -		" free:%lu free_pcp:%lu free_cma:%lu\n",
> -		global_node_page_state(NR_ACTIVE_ANON),
> -		global_node_page_state(NR_INACTIVE_ANON),
> -		global_node_page_state(NR_ISOLATED_ANON),
> -		global_node_page_state(NR_ACTIVE_FILE),
> -		global_node_page_state(NR_INACTIVE_FILE),
> -		global_node_page_state(NR_ISOLATED_FILE),
> -		global_node_page_state(NR_UNEVICTABLE),
> -		global_node_page_state(NR_FILE_DIRTY),
> -		global_node_page_state(NR_WRITEBACK),
> -		global_node_page_state(NR_UNSTABLE_NFS),
> -		global_page_state(NR_SLAB_RECLAIMABLE),
> -		global_page_state(NR_SLAB_UNRECLAIMABLE),
> -		global_node_page_state(NR_FILE_MAPPED),
> -		global_node_page_state(NR_SHMEM),
> -		global_page_state(NR_PAGETABLE),
> -		global_page_state(NR_BOUNCE),
> -		global_page_state(NR_FREE_PAGES),
> -		free_pcp,
> -		global_page_state(NR_FREE_CMA_PAGES));
> +	printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n",
> +	       global_node_page_state(NR_ACTIVE_ANON),
> +	       global_node_page_state(NR_INACTIVE_ANON),
> +	       global_node_page_state(NR_ISOLATED_ANON));
> +	printk("active_file:%lu inactive_file:%lu isolated_file:%lu\n",
> +	       global_node_page_state(NR_ACTIVE_FILE),
> +	       global_node_page_state(NR_INACTIVE_FILE),
> +	       global_node_page_state(NR_ISOLATED_FILE));
> +	printk("unevictable:%lu dirty:%lu writeback:%lu unstable:%lu\n",
> +	       global_node_page_state(NR_UNEVICTABLE),
> +	       global_node_page_state(NR_FILE_DIRTY),
> +	       global_node_page_state(NR_WRITEBACK),
> +	       global_node_page_state(NR_UNSTABLE_NFS));
> +	printk("slab_reclaimable:%lu slab_unreclaimable:%lu\n",
> +	       global_page_state(NR_SLAB_RECLAIMABLE),
> +	       global_page_state(NR_SLAB_UNRECLAIMABLE));
> +	printk("mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
> +	       global_node_page_state(NR_FILE_MAPPED),
> +	       global_node_page_state(NR_SHMEM),
> +	       global_page_state(NR_PAGETABLE),
> +	       global_page_state(NR_BOUNCE));
> +	printk("free:%lu free_pcp:%lu free_cma:%lu\n",
> +	       global_page_state(NR_FREE_PAGES),
> +	       free_pcp,
> +	       global_page_state(NR_FREE_CMA_PAGES));

a side note:

this can make it harder to read, in _the worst case_. one printk()
guaranteed that we would see a single line in the serial log/etc.
the sort of a problem with multiple printks is that printks coming
from other CPUs will split that "previously single" line.

just a notice. up to MM people to decide.

	-ss