Commit f370e1e2 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

perf_counter: add PERF_RECORD_CPU 



Allow recording the CPU number the event was generated on.

RFC: this leaves a u32 as reserved, should we fill in the
     node_id() there, or leave this open for future extention,
     as userspace can already easily do the cpu->node mapping
     if needed.

[ Impact: extend perfcounter output record format ]

Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <20090508170029.008627711@chello.nl>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent a85f61ab

include/linux/perf_counter.h

+2 −0
Original line number Diff line number Diff line
@@ -105,6 +105,7 @@ enum perf_counter_record_format { 
	PERF_RECORD_GROUP	= 1U << 4,

	PERF_RECORD_CALLCHAIN	= 1U << 5,

	PERF_RECORD_CONFIG	= 1U << 6,

	PERF_RECORD_CPU		= 1U << 7,

};



/*
@@ -260,6 +261,7 @@ enum perf_event_type { 
	 * 	{ u64			time;     } && PERF_RECORD_TIME

	 * 	{ u64			addr;     } && PERF_RECORD_ADDR

	 * 	{ u64			config;   } && PERF_RECORD_CONFIG

	 * 	{ u32			cpu, res; } && PERF_RECORD_CPU

	 *

	 * 	{ u64			nr;

	 * 	  { u64 event, val; } 	cnt[nr];  } && PERF_RECORD_GROUP

kernel/perf_counter.c

+13 −0
Original line number Diff line number Diff line
@@ -1956,6 +1956,9 @@ static void perf_counter_output(struct perf_counter *counter, 
	struct perf_callchain_entry *callchain = NULL;

	int callchain_size = 0;

	u64 time;

	struct {

		u32 cpu, reserved;

	} cpu_entry;



	header.type = 0;

	header.size = sizeof(header);
@@ -1999,6 +2002,13 @@ static void perf_counter_output(struct perf_counter *counter, 
		header.size += sizeof(u64);

	}



	if (record_type & PERF_RECORD_CPU) {

		header.type |= PERF_RECORD_CPU;

		header.size += sizeof(cpu_entry);



		cpu_entry.cpu = raw_smp_processor_id();

	}



	if (record_type & PERF_RECORD_GROUP) {

		header.type |= PERF_RECORD_GROUP;

		header.size += sizeof(u64) +
@@ -2037,6 +2047,9 @@ static void perf_counter_output(struct perf_counter *counter, 
	if (record_type & PERF_RECORD_CONFIG)

		perf_output_put(&handle, counter->hw_event.config);



	if (record_type & PERF_RECORD_CPU)

		perf_output_put(&handle, cpu_entry);



	/*

	 * XXX PERF_RECORD_GROUP vs inherited counters seems difficult.

	 */

CRA Git | Maintained and supported by SUSTech CRA and CCSE