memcg: remove redundant message at swapon (627991a2) · Commits · 戴 / test

It's pointed out that swap_cgroup's message at swapon() is nonsense. Because * It can be calculated very easily if all necessary information is written in Kconfig. * It's not necessary to annoying people at every swapon(). In other view, now, memory usage per swp_entry is reduced to 2bytes from 8bytes(64bit) and I think it's reasonably small. Reported-by:

Hugh Dickins <hugh@veritas.com> Signed-off-by:

KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

init/Kconfig

+2 −0

Original line number	Diff line number	Diff line
		@@ -597,6 +597,8 @@ config CGROUP_MEM_RES_CTLR_SWAP
		is disabled by boot option, this will be automatically disabled and
		there will be no overhead from this. Even when you set this config=y,
		if boot option "noswapaccount" is set, swap will not be accounted.
		Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
		size is 4096bytes, 512k per 1Gbytes of swap.

		endif # CGROUPS

mm/page_cgroup.c

+0 −7

Original line number	Diff line number	Diff line
		@@ -426,13 +426,6 @@ int swap_cgroup_swapon(int type, unsigned long max_pages)
		}
		mutex_unlock(&swap_cgroup_mutex);

		printk(KERN_INFO
		"swap_cgroup: uses %ld bytes of vmalloc for pointer array space"
		" and %ld bytes to hold mem_cgroup information per swap ents\n",
		array_size, length * PAGE_SIZE);
		printk(KERN_INFO
		"swap_cgroup can be disabled by noswapaccount boot option.\n");

		return 0;
		nomem:
		printk(KERN_INFO "couldn't allocate enough memory for swap_cgroup.\n");

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