oprofile/x86: return -EBUSY if counters are already reserved

In case a counter is already reserved by the watchdog or perf_event
subsystem, oprofile ignored this counters silently. This case is
handled now and oprofile_setup() now reports an error.

Signed-off-by: Robert Richter <robert.richter@amd.com>

1 files changed, 13 insertions, 1 deletions

diff --git a/arch/x86/oprofile/op_model_p4.c b/arch/x86/oprofile/op_model_p4.c
index 7cc80df330d..182558dd551 100644
--- a/arch/x86/oprofile/op_model_p4.c
+++ b/arch/x86/oprofile/op_model_p4.c
@@ -404,7 +404,7 @@ static void p4_shutdown(struct op_msrs const * const msrs)
 	}
 }
 
-static void p4_fill_in_addresses(struct op_msrs * const msrs)
+static int p4_fill_in_addresses(struct op_msrs * const msrs)
 {
 	unsigned int i;
 	unsigned int addr, cccraddr, stag;
@@ -486,6 +486,18 @@ static void p4_fill_in_addresses(struct op_msrs * const msrs)
 			msrs->controls[i++].addr = MSR_P4_CRU_ESCR5;
 		}
 	}
+
+	for (i = 0; i < num_counters; ++i) {
+		if (!counter_config[i].enabled)
+			continue;
+		if (msrs->controls[i].addr)
+			continue;
+		op_x86_warn_reserved(i);
+		p4_shutdown(msrs);
+		return -EBUSY;
+	}
+
+	return 0;
 }