[PATCH -tip/perf/core] perf, x86: P4 PMU - Drop redundantWARN_ON_ONCE

[Cyrill Gorcunov]

This WARN_ON_ONCE triggers a false alarm on SMP because
nmi-watchdog uses a single global 'wd_hw_attr' variable
to serve perf event attributes and once p4_hw_watchdog_set_attr
has modified it subsequent calls on the rest cpus trigger
the warning.

It is safe to simply drop it since we know the caller may
pass already altered type and config.

Repoted-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
Signed-off-by: Cyrill Gorcunov <gorcunov@xxxxxxxxxx>
---
 arch/x86/kernel/cpu/perf_event_p4.c |    3 ---
 1 file changed, 3 deletions(-)

Index: linux-2.6.git/arch/x86/kernel/cpu/perf_event_p4.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/cpu/perf_event_p4.c
+++ linux-2.6.git/arch/x86/kernel/cpu/perf_event_p4.c
@@ -726,9 +726,6 @@ static void p4_hw_watchdog_set_attr(stru
 	 * that named "non-sleeping" ticks as recommended
 	 * by Intel SDM Vol3b.
 	 */
-	WARN_ON_ONCE(wd_attr->type	!= PERF_TYPE_HARDWARE ||
-		     wd_attr->config	!= PERF_COUNT_HW_CPU_CYCLES);
-
 	wd_attr->type	= PERF_TYPE_RAW;
 	wd_attr->config	=
 		p4_config_pack_escr(P4_ESCR_EVENT(P4_EVENT_EXECUTION_EVENT)		|
--
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