Messages in this thread | | | Date | Sat, 16 Oct 2010 08:27:25 +0200 | From | Ingo Molnar <> | Subject | Re: [RFC][PATCH 7/7] perf: Optimize sw events |
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* Peter Zijlstra <peterz@infradead.org> wrote:
> On Fri, 2010-10-15 at 11:16 +0200, Peter Zijlstra wrote: > > On Thu, 2010-10-14 at 22:34 +0200, Peter Zijlstra wrote: > > > > > Index: linux-2.6/include/linux/perf_event.h > > > =================================================================== > > > --- linux-2.6.orig/include/linux/perf_event.h > > > +++ linux-2.6/include/linux/perf_event.h > > > @@ -1013,15 +1013,17 @@ static inline void perf_fetch_caller_reg > > > static inline void > > > perf_sw_event(u32 event_id, u64 nr, int nmi, struct pt_regs *regs, u64 addr) > > > { > > > - if (atomic_read(&perf_swevent_enabled[event_id])) { > > > - struct pt_regs hot_regs; > > > + struct pt_regs hot_regs; > > > > > > - if (!regs) { > > > - perf_fetch_caller_regs(&hot_regs); > > > - regs = &hot_regs; > > > - } > > > - __perf_sw_event(event_id, nr, nmi, regs, addr); > > > + JUMP_LABEL(&perf_swevent_enabled[event_id], have_event); > > > + return; > > > + > > > +have_event: > > > + if (!regs) { > > > + perf_fetch_caller_regs(&hot_regs); > > > + regs = &hot_regs; > > > } > > > + __perf_sw_event(event_id, nr, nmi, regs, addr); > > > } > > > > > > > OK, so it appears I only compile tested this bit without jump_label > > support, with that bit added back this horribly fails to compile like: > > > > In file included from /usr/src/linux-2.6/arch/x86/mm/fault.c:13: > > /usr/src/linux-2.6/include/linux/perf_event.h: In function ‘perf_sw_event.clone.0’: > > /usr/src/linux-2.6/include/linux/perf_event.h:1018: warning: asm operand 0 probably doesn’t match constraints > > /usr/src/linux-2.6/include/linux/perf_event.h:1018: error: impossible constraint in ‘asm’ > > > > Ah, figured it out, it needs __attribute__((always_inline)), otherwise > we end up with multiple keys for one label, which will clealy not work. > > I thought we had a __force_inline macro but I can't seem to find that.
It's called __always_inline.
Thanks,
Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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