path: root/arch/powerpc/include/asm/hw_irq.h
diff options
authorPaul Mackerras <paulus@samba.org>2009-06-17 21:50:04 +1000
committerIngo Molnar <mingo@elte.hu>2009-06-18 11:11:44 +0200
commit105988c015943e77092a6568bc5fb7e386df6ccd (patch)
treebd352fe5e68a66de2e08a8b91c8f8cccf422f346 /arch/powerpc/include/asm/hw_irq.h
parenta73c7d84a1975b44c0ebd03c2dec288af1426349 (diff)
perf_counter: powerpc: Enable use of software counters on 32-bit powerpc
This enables the perf_counter subsystem on 32-bit powerpc. Since we don't have any support for hardware counters on 32-bit powerpc yet, only software counters can be used. Besides selecting HAVE_PERF_COUNTERS for 32-bit powerpc as well as 64-bit, the main thing this does is add an implementation of set_perf_counter_pending(). This needs to arrange for perf_counter_do_pending() to be called when interrupts are enabled. Rather than add code to local_irq_restore as 64-bit does, the 32-bit set_perf_counter_pending() generates an interrupt by setting the decrementer to 1 so that a decrementer interrupt will become pending in 1 or 2 timebase ticks (if a decrementer interrupt isn't already pending). When interrupts are enabled, timer_interrupt() will be called, and some new code in there calls perf_counter_do_pending(). We use a per-cpu array of flags to indicate whether we need to call perf_counter_do_pending() or not. This introduces a couple of new Kconfig symbols: PPC_HAVE_PMU_SUPPORT, which is selected by processor families for which we have hardware PMU support (currently only PPC64), and PPC_PERF_CTRS, which enables the powerpc-specific perf_counter back-end. Signed-off-by: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: linuxppc-dev@ozlabs.org Cc: benh@kernel.crashing.org LKML-Reference: <19000.55404.103840.393470@cargo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/powerpc/include/asm/hw_irq.h')
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h
index 10a642df014..867ab8ed69b 100644
--- a/arch/powerpc/include/asm/hw_irq.h
+++ b/arch/powerpc/include/asm/hw_irq.h
@@ -131,6 +131,8 @@ static inline int irqs_disabled_flags(unsigned long flags)
struct irq_chip;
+#ifdef CONFIG_PPC64
static inline unsigned long test_perf_counter_pending(void)
unsigned long x;
@@ -154,8 +156,9 @@ static inline void clear_perf_counter_pending(void)
"r" (0),
"i" (offsetof(struct paca_struct, perf_counter_pending)));
+#endif /* CONFIG_PPC64 */
static inline unsigned long test_perf_counter_pending(void)