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Revision 511e19b9e2112463c33a744ecb8a798056074408 authored by Namhyung Kim on 19 December 2022, 20:17:30 UTC, committed by Arnaldo Carvalho de Melo on 21 December 2022, 17:52:39 UTC 
perf lock contention: Add -L/--lock-filter option
 
The -L/--lock-filter option is to filter only given locks.  The locks
can be specified by address or name (if exists).

  $ sudo ./perf lock record -a  sleep 1

  $ sudo ./perf lock con -l
   contended  total wait  max wait  avg wait           address  symbol

          57     1.11 ms  42.83 us  19.54 us  ffff9f4140059000
          15   280.88 us  23.51 us  18.73 us  ffffffff9d007a40  jiffies_lock
           1    20.49 us  20.49 us  20.49 us  ffffffff9d0d50c0  rcu_state
           1     9.02 us   9.02 us   9.02 us  ffff9f41759e9ba0

  $ sudo ./perf lock con -L jiffies_lock,rcu_state
   contended  total wait  max wait  avg wait      type  caller

          15   280.88 us  23.51 us  18.73 us  spinlock  tick_sched_do_timer+0x93
           1    20.49 us  20.49 us  20.49 us  spinlock  __softirqentry_text_start+0xeb

  $ sudo ./perf lock con -L ffff9f4140059000
   contended  total wait  max wait  avg wait      type  caller

          38   779.40 us  42.83 us  20.51 us  spinlock  worker_thread+0x50
          11   216.30 us  39.87 us  19.66 us  spinlock  queue_work_on+0x39
           8   118.13 us  20.51 us  14.77 us  spinlock  kthread+0xe5

Committer testing:

  # uname -a
  Linux quaco 6.0.12-200.fc36.x86_64 #1 SMP PREEMPT_DYNAMIC Thu Dec 8 17:15:53 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
  # perf lock record
  ^C[ perf record: Woken up 1 times to write data ]
  # perf lock con -L jiffies_lock,rcu_state
   contended   total wait     max wait     avg wait         type   caller

  # perf lock con
   contended   total wait     max wait     avg wait         type   caller

           1      9.06 us      9.06 us      9.06 us     spinlock   call_timer_fn+0x24
  # perf lock con -L call
  ignore unknown symbol: call
   contended   total wait     max wait     avg wait         type   caller

           1      9.06 us      9.06 us      9.06 us     spinlock   call_timer_fn+0x24
  #

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Blake Jones <blakejones@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20221219201732.460111-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
1 parent 529772c
Raw File
gen_crc64table.c 
// SPDX-License-Identifier: GPL-2.0
/*
 * Generate lookup table for the table-driven CRC64 calculation.
 *
 * gen_crc64table is executed in kernel build time and generates
 * lib/crc64table.h. This header is included by lib/crc64.c for
 * the table-driven CRC64 calculation.
 *
 * See lib/crc64.c for more information about which specification
 * and polynomial arithmetic that gen_crc64table.c follows to
 * generate the lookup table.
 *
 * Copyright 2018 SUSE Linux.
 *   Author: Coly Li <colyli@suse.de>
 */
#include <inttypes.h>
#include <stdio.h>

#define CRC64_ECMA182_POLY 0x42F0E1EBA9EA3693ULL
#define CRC64_ROCKSOFT_POLY 0x9A6C9329AC4BC9B5ULL

static uint64_t crc64_table[256] = {0};
static uint64_t crc64_rocksoft_table[256] = {0};

static void generate_reflected_crc64_table(uint64_t table[256], uint64_t poly)
{
	uint64_t i, j, c, crc;

	for (i = 0; i < 256; i++) {
		crc = 0ULL;
		c = i;

		for (j = 0; j < 8; j++) {
			if ((crc ^ (c >> j)) & 1)
				crc = (crc >> 1) ^ poly;
			else
				crc >>= 1;
		}
		table[i] = crc;
	}
}

static void generate_crc64_table(uint64_t table[256], uint64_t poly)
{
	uint64_t i, j, c, crc;

	for (i = 0; i < 256; i++) {
		crc = 0;
		c = i << 56;

		for (j = 0; j < 8; j++) {
			if ((crc ^ c) & 0x8000000000000000ULL)
				crc = (crc << 1) ^ poly;
			else
				crc <<= 1;
			c <<= 1;
		}

		table[i] = crc;
	}
}

static void output_table(uint64_t table[256])
{
	int i;

	for (i = 0; i < 256; i++) {
		printf("\t0x%016" PRIx64 "ULL", table[i]);
		if (i & 0x1)
			printf(",\n");
		else
			printf(", ");
	}
	printf("};\n");
}

static void print_crc64_tables(void)
{
	printf("/* this file is generated - do not edit */\n\n");
	printf("#include <linux/types.h>\n");
	printf("#include <linux/cache.h>\n\n");
	printf("static const u64 ____cacheline_aligned crc64table[256] = {\n");
	output_table(crc64_table);

	printf("\nstatic const u64 ____cacheline_aligned crc64rocksofttable[256] = {\n");
	output_table(crc64_rocksoft_table);
}

int main(int argc, char *argv[])
{
	generate_crc64_table(crc64_table, CRC64_ECMA182_POLY);
	generate_reflected_crc64_table(crc64_rocksoft_table, CRC64_ROCKSOFT_POLY);
	print_crc64_tables();
	return 0;
}
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