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Revert "memcg: enable accounting for pollfd and select bits arrays"

This reverts commit b655843444152c0a14b749308e4cb35d91cbcf0b.

Just like with the memcg lock accounting, the kernel test robot reports
a sizeable performance regression for this commit, and while it clearly
does the rigth thing in theory, we'll need to look at just how to avoid
or minimize the performance overhead of the memcg accounting.

People already have suggestions on how to do that, but it's "future
work".

So revert it for now.

[ Note: the first link below is for this same commit but a different
commit ID, because it's the kernel test robot ended up noticing it in
Andrew Morton's patch queue ]

Link: https://lore.kernel.org/lkml/20210905132732.GC15026@xsang-OptiPlex-9020/
Link: https://lore.kernel.org/lkml/20210907150757.GE17617@xsang-OptiPlex-9020/
Acked-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Linus Torvalds 0bcfe68b 3754707b

+2 -2
+2 -2
fs/select.c
··· 655 655 goto out_nofds; 656 656 657 657 alloc_size = 6 * size; 658 - bits = kvmalloc(alloc_size, GFP_KERNEL_ACCOUNT); 658 + bits = kvmalloc(alloc_size, GFP_KERNEL); 659 659 if (!bits) 660 660 goto out_nofds; 661 661 } ··· 1000 1000 1001 1001 len = min(todo, POLLFD_PER_PAGE); 1002 1002 walk = walk->next = kmalloc(struct_size(walk, entries, len), 1003 - GFP_KERNEL_ACCOUNT); 1003 + GFP_KERNEL); 1004 1004 if (!walk) { 1005 1005 err = -ENOMEM; 1006 1006 goto out_fds;