Messages in this thread | | | Date | Tue, 19 Jun 2001 10:48:48 -0500 | From | Timur Tabi <> | Subject | Re: gnu asm help... |
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** Reply to message from "Petr Vandrovec" <VANDROVE@vc.cvut.cz> on Tue, 19 Jun 2001 01:36:26 MET-1
> No. Another CPU might increment value between LOCK INCL and > fetching v->counter. On ia32 architecture you are almost out of > luck. You can either try building atomic_inc around CMPXCHG, > using it as conditional store (but CMPXCHG is not available > on i386), or you can just guard your atomic variable with > spinlock - but in that case there is no reason for using atomic_t > at all.
Oh, I see the problem. You could do something like this:
cli mov %0, %%eax inc %%eax mov %%eax, %0 sti
and then return eax, but that won't work on SMP (whereas the "lock inc" does). Doing a global cli might work, though.
-- Timur Tabi - ttabi@interactivesi.com Interactive Silicon - http://www.interactivesi.com
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