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powerpc/64s/radix: Enable huge vmalloc mappings
authorNicholas Piggin <npiggin@gmail.com>
Mon, 3 May 2021 09:17:55 +0000 (19:17 +1000)
committerMichael Ellerman <mpe@ellerman.id.au>
Tue, 4 May 2021 01:06:45 +0000 (11:06 +1000)
commit8abddd968a303db75e4debe77a3df484164f1f33
treeb3ea95c6553f6738df1ca51c25794c701e7f69d0
parent562d1e207d322e6346e8db91bbd11d94f16427d2
powerpc/64s/radix: Enable huge vmalloc mappings

This reduces TLB misses by nearly 30x on a `git diff` workload on a
2-node POWER9 (59,800 -> 2,100) and reduces CPU cycles by 0.54%, due
to vfs hashes being allocated with 2MB pages.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210503091755.613393-1-npiggin@gmail.com
Documentation/admin-guide/kernel-parameters.txt
arch/powerpc/Kconfig
arch/powerpc/kernel/module.c