Messages in this thread | | | Subject | Re: [PATCH] make atomic_t volatile on all architectures | From | Martin Schwidefsky <> | Date | Thu, 09 Aug 2007 19:57:55 +0200 |
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On Thu, 2007-08-09 at 13:36 -0400, Chuck Ebbert wrote: > > Fair enough. Casting to (volatile int *) will give us the behavior > > people expect when using atomic_t without needing to use inefficient > > barriers. > > > > You can use this forget() macro to make the compiler reread a > variable: > > #define forget(var) asm volatile ("" : "=m"(var))
You need to specify a "m"(var) input constraint as well. Without it the compiler might remove the initialization of var. E.g.
void fn(void) { int var = 0; forget(var); /* now var can have any value. */ }
-- blue skies, Martin.
"Reality continues to ruin my life." - Calvin.
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