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	 c45c6ea2e5
			
		
	
	
		c45c6ea2e5
		
	
	
	
	
		
			
			This patch adds a -C option to stat, record, top to designate a list of CPUs to monitor. CPUs can be specified as a comma-separated list or ranges, no space allowed. Examples: $ perf record -a -C0-1,4-7 sleep 1 $ perf top -C0-4 $ perf stat -a -C1,2,3,4 sleep 1 With perf record in per-thread mode with inherit mode on, samples are collected only when the thread runs on the designated CPUs. The -C option does not turn on system-wide mode automatically. Cc: David S. Miller <davem@davemloft.net> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <4bff9496.d345d80a.41fe.7b00@mx.google.com> Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
		
			
				
	
	
		
			115 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			115 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include "util.h"
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| #include "../perf.h"
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| #include "cpumap.h"
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| #include <assert.h>
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| #include <stdio.h>
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| 
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| int cpumap[MAX_NR_CPUS];
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| 
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| static int default_cpu_map(void)
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| {
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| 	int nr_cpus, i;
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| 
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| 	nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
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| 	assert(nr_cpus <= MAX_NR_CPUS);
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| 	assert((int)nr_cpus >= 0);
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| 
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| 	for (i = 0; i < nr_cpus; ++i)
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| 		cpumap[i] = i;
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| 
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| 	return nr_cpus;
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| }
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| 
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| static int read_all_cpu_map(void)
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| {
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| 	FILE *onlnf;
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| 	int nr_cpus = 0;
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| 	int n, cpu, prev;
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| 	char sep;
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| 
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| 	onlnf = fopen("/sys/devices/system/cpu/online", "r");
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| 	if (!onlnf)
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| 		return default_cpu_map();
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| 
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| 	sep = 0;
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| 	prev = -1;
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| 	for (;;) {
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| 		n = fscanf(onlnf, "%u%c", &cpu, &sep);
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| 		if (n <= 0)
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| 			break;
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| 		if (prev >= 0) {
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| 			assert(nr_cpus + cpu - prev - 1 < MAX_NR_CPUS);
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| 			while (++prev < cpu)
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| 				cpumap[nr_cpus++] = prev;
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| 		}
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| 		assert (nr_cpus < MAX_NR_CPUS);
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| 		cpumap[nr_cpus++] = cpu;
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| 		if (n == 2 && sep == '-')
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| 			prev = cpu;
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| 		else
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| 			prev = -1;
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| 		if (n == 1 || sep == '\n')
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| 			break;
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| 	}
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| 	fclose(onlnf);
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| 	if (nr_cpus > 0)
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| 		return nr_cpus;
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| 
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| 	return default_cpu_map();
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| }
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| 
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| int read_cpu_map(const char *cpu_list)
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| {
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| 	unsigned long start_cpu, end_cpu = 0;
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| 	char *p = NULL;
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| 	int i, nr_cpus = 0;
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| 
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| 	if (!cpu_list)
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| 		return read_all_cpu_map();
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| 
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| 	if (!isdigit(*cpu_list))
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| 		goto invalid;
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| 
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| 	while (isdigit(*cpu_list)) {
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| 		p = NULL;
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| 		start_cpu = strtoul(cpu_list, &p, 0);
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| 		if (start_cpu >= INT_MAX
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| 		    || (*p != '\0' && *p != ',' && *p != '-'))
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| 			goto invalid;
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| 
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| 		if (*p == '-') {
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| 			cpu_list = ++p;
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| 			p = NULL;
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| 			end_cpu = strtoul(cpu_list, &p, 0);
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| 
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| 			if (end_cpu >= INT_MAX || (*p != '\0' && *p != ','))
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| 				goto invalid;
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| 
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| 			if (end_cpu < start_cpu)
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| 				goto invalid;
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| 		} else {
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| 			end_cpu = start_cpu;
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| 		}
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| 
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| 		for (; start_cpu <= end_cpu; start_cpu++) {
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| 			/* check for duplicates */
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| 			for (i = 0; i < nr_cpus; i++)
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| 				if (cpumap[i] == (int)start_cpu)
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| 					goto invalid;
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| 
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| 			assert(nr_cpus < MAX_NR_CPUS);
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| 			cpumap[nr_cpus++] = (int)start_cpu;
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| 		}
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| 		if (*p)
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| 			++p;
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| 
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| 		cpu_list = p;
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| 	}
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| 	if (nr_cpus > 0)
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| 		return nr_cpus;
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| 
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| 	return default_cpu_map();
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| invalid:
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| 	return -1;
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| }
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