Messages in this thread | | | Date | Thu, 30 Mar 2017 08:43:39 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH 4/8] asm-generic: add atomic-instrumented.h |
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* Mark Rutland <mark.rutland@arm.com> wrote:
> With some minimal CPP, it can be a lot more manageable: > > ---- > #define INSTR_ATOMIC_XCHG(order) \ > static __always_inline int atomic_xchg##order(atomic_t *v, int i) \ > { \ > kasan_check_write(v, sizeof(*v)); \ > arch_atomic_xchg##order(v, i); \ > } > > #define INSTR_ATOMIC_XCHG() > > #ifdef arch_atomic_xchg_relaxed > INSTR_ATOMIC_XCHG(_relaxed) > #define atomic_xchg_relaxed atomic_xchg_relaxed > #endif > > #ifdef arch_atomic_xchg_acquire > INSTR_ATOMIC_XCHG(_acquire) > #define atomic_xchg_acquire atomic_xchg_acquire > #endif > > #ifdef arch_atomic_xchg_relaxed > INSTR_ATOMIC_XCHG(_relaxed) > #define atomic_xchg_relaxed atomic_xchg_relaxed > #endif
Yeah, small detail: the third one wants to be _release, right?
> Is there any objection to some light CPP usage as above for adding the > {relaxed,acquire,release} variants?
No objection from me to that way of writing it, this still looks very readable, and probably more readable than the verbose variants. It's similar in style to linux/atomic.h which has a good balance of C versus CPP.
What I objected to was the deep nested code generation approach in the original patch.
CPP is fine in many circumstances, but there's a level of (ab-)use where it becomes counterproductive.
Thanks,
Ingo
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