We want to implement a ppc64 specific version of atomic_inc_not_zero
so wrap it in an ifdef to allow it to be overridden.
Signed-off-by: Anton Blanchard <[email protected]>
Acked-by: Mike Frysinger <[email protected]>
Signed-off-by: Benjamin Herrenschmidt <[email protected]>
After changing all consumers of atomics to include <linux/atomic.h>, we
ran into some compile time errors due to this dependency chain:
linux/atomic.h
-> asm/atomic.h
-> asm-generic/atomic-long.h
where atomic-long.h could use funcs defined later in linux/atomic.h
without a prototype. This patches moves the code that includes
asm-generic/atomic*.h to linux/atomic.h.
Archs that need <asm-generic/atomic64.h> need to select
CONFIG_GENERIC_ATOMIC64 from now on (some of them used to include it
unconditionally).
Compile tested on i386 and x86_64 with allnoconfig.
Signed-off-by: Arun Sharma <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: David Miller <[email protected]>
Acked-by: Mike Frysinger <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
An atomic_or() function is needed by TREE_RCU to avoid deadlock, so
add a generic version.
Signed-off-by: Paul E. McKenney <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Followup of perf tools session in Netfilter WorkShop 2010
In the network stack we make high usage of atomic_inc_not_zero() in
contexts we know the probable value of atomic before increment (2 for udp
sockets for example)
Using a special version of atomic_inc_not_zero() giving this hint can help
processor to use less bus transactions.
On x86 (MESI protocol) for example, this avoids entering Shared state,
because "lock cmpxchg" issues an RFO (Read For Ownership)
akpm: Adds a new include/linux/atomic.h. This means that new code should
henceforth include linux/atomic.h and not asm/atomic.h. The presence of
include/linux/atomic.h will in fact cause checkpatch.pl to warn about use
of asm/atomic.h. The new include/linux/atomic.h becomes the place where
arch-neutral atomic_t code should be placed.
[[email protected]: coding-style fixes]
Signed-off-by: Eric Dumazet <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: David Miller <[email protected]>
Cc: "Paul E. McKenney" <[email protected]>
Cc: Nick Piggin <[email protected]>
Reviewed-by: "Paul E. McKenney" <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Shaohua Li