From f7e688476f90f8bdeeb23dd64bbd2b4133c827f4 Mon Sep 17 00:00:00 2001 From: Fengguang Wu Date: Thu, 25 Oct 2012 12:14:43 +1100 Subject: [PATCH] h8300: select generic atomic64_t support Rationales from Eric: So I just looked a little deeper and it appears architectures that do not support atomic64_t are broken. The generic atomic64 support came in 2009 to support the perf subsystem with the expectation that all architectures would implement atomic64 support. Furthermore upon inspection of the kernel atomic64_t is used in a fair number of places beyond the performance counters: block/blk-cgroup.c drivers/acpi/apei/ drivers/block/rbd.c drivers/crypto/nx/nx.h drivers/gpu/drm/radeon/radeon.h drivers/infiniband/hw/ipath/ drivers/infiniband/hw/qib/ drivers/staging/octeon/ fs/xfs/ include/linux/perf_event.h include/net/netfilter/nf_conntrack_acct.h kernel/events/ kernel/trace/ net/mac80211/key.h net/rds/ The block control group, infiniband, xfs, crypto, 802.11, netfilter. Nothing quite so fundamental as fs/namespace.c but definitely in multiplatform-code that should work, and is already broken on those architecutres. Looking at the implementation of atomic64_add_return in lib/atomic64.c the code looks as efficient as these kinds of things get. Which leads me to the conclusion that we need atomic64 support on all architectures. Signed-off-by: Fengguang Wu Cc: "Eric W. Biederman" Cc: Yoshinori Sato Signed-off-by: Andrew Morton --- arch/h8300/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig index 98fabd10e95f..2d2efb653ee0 100644 --- a/arch/h8300/Kconfig +++ b/arch/h8300/Kconfig @@ -3,6 +3,7 @@ config H8300 default y select HAVE_IDE select HAVE_GENERIC_HARDIRQS + select GENERIC_ATOMIC64 select HAVE_UID16 select ARCH_WANT_IPC_PARSE_VERSION select GENERIC_IRQ_SHOW -- 2.39.5