[tip:perfcounters/core] perf top: Convert to Git option parsing

From: tip-bot for Ingo Molnar
Date: Tue May 26 2009 - 07:37:35 EST


Commit-ID: b456bae0ff4f3cf91639dd32b2bfc49b1c30b4b0
Gitweb: http://git.kernel.org/tip/b456bae0ff4f3cf91639dd32b2bfc49b1c30b4b0
Author: Ingo Molnar <mingo@xxxxxxx>
AuthorDate: Tue, 26 May 2009 09:17:18 +0200
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Tue, 26 May 2009 12:33:04 +0200

perf top: Convert to Git option parsing

Remove getopt usage and use Git's much more advanced and more compact
command option library.

Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Corey Ashford <cjashfor@xxxxxxxxxxxxxxxxxx>
Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: John Kacur <jkacur@xxxxxxxxxx>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>


---
Documentation/perf_counter/builtin-top.c | 559 ++++++------------------------
1 files changed, 105 insertions(+), 454 deletions(-)

diff --git a/Documentation/perf_counter/builtin-top.c b/Documentation/perf_counter/builtin-top.c
index 626b320..87b925c 100644
--- a/Documentation/perf_counter/builtin-top.c
+++ b/Documentation/perf_counter/builtin-top.c
@@ -45,8 +45,10 @@

#include "perf.h"
#include "util/util.h"
+#include "util/util.h"
+#include "util/parse-options.h"
+#include "util/parse-events.h"

-#include <getopt.h>
#include <assert.h>
#include <fcntl.h>

@@ -70,8 +72,7 @@

static int system_wide = 0;

-static int nr_counters = 0;
-static __u64 event_id[MAX_COUNTERS] = {
+static __u64 default_event_id[MAX_COUNTERS] = {
EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK),
EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CONTEXT_SWITCHES),
EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_MIGRATIONS),
@@ -88,7 +89,7 @@ static int fd[MAX_NR_CPUS][MAX_COUNTERS];

static __u64 count_filter = 100;

-static int tid = -1;
+static int target_pid = -1;
static int profile_cpu = -1;
static int nr_cpus = 0;
static int nmi = 1;
@@ -100,8 +101,6 @@ static int use_mmap = 0;
static int use_munmap = 0;
static int freq = 0;

-static char *vmlinux;
-
static char *sym_filter;
static unsigned long filter_start;
static unsigned long filter_end;
@@ -110,18 +109,6 @@ static int delay_secs = 2;
static int zero;
static int dump_symtab;

-static int scale;
-
-struct source_line {
- uint64_t EIP;
- unsigned long count;
- char *line;
- struct source_line *next;
-};
-
-static struct source_line *lines;
-static struct source_line **lines_tail;
-
static const unsigned int default_count[] = {
1000000,
1000000,
@@ -131,194 +118,6 @@ static const unsigned int default_count[] = {
10000,
};

-static char *hw_event_names[] = {
- "CPU cycles",
- "instructions",
- "cache references",
- "cache misses",
- "branches",
- "branch misses",
- "bus cycles",
-};
-
-static char *sw_event_names[] = {
- "cpu clock ticks",
- "task clock ticks",
- "pagefaults",
- "context switches",
- "CPU migrations",
- "minor faults",
- "major faults",
-};
-
-struct event_symbol {
- __u64 event;
- char *symbol;
-};
-
-static struct event_symbol event_symbols[] = {
- {EID(PERF_TYPE_HARDWARE, PERF_COUNT_CPU_CYCLES), "cpu-cycles", },
- {EID(PERF_TYPE_HARDWARE, PERF_COUNT_CPU_CYCLES), "cycles", },
- {EID(PERF_TYPE_HARDWARE, PERF_COUNT_INSTRUCTIONS), "instructions", },
- {EID(PERF_TYPE_HARDWARE, PERF_COUNT_CACHE_REFERENCES), "cache-references", },
- {EID(PERF_TYPE_HARDWARE, PERF_COUNT_CACHE_MISSES), "cache-misses", },
- {EID(PERF_TYPE_HARDWARE, PERF_COUNT_BRANCH_INSTRUCTIONS), "branch-instructions", },
- {EID(PERF_TYPE_HARDWARE, PERF_COUNT_BRANCH_INSTRUCTIONS), "branches", },
- {EID(PERF_TYPE_HARDWARE, PERF_COUNT_BRANCH_MISSES), "branch-misses", },
- {EID(PERF_TYPE_HARDWARE, PERF_COUNT_BUS_CYCLES), "bus-cycles", },
-
- {EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_CLOCK), "cpu-clock", },
- {EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK), "task-clock", },
- {EID(PERF_TYPE_SOFTWARE, PERF_COUNT_PAGE_FAULTS), "page-faults", },
- {EID(PERF_TYPE_SOFTWARE, PERF_COUNT_PAGE_FAULTS), "faults", },
- {EID(PERF_TYPE_SOFTWARE, PERF_COUNT_PAGE_FAULTS_MIN), "minor-faults", },
- {EID(PERF_TYPE_SOFTWARE, PERF_COUNT_PAGE_FAULTS_MAJ), "major-faults", },
- {EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CONTEXT_SWITCHES), "context-switches", },
- {EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CONTEXT_SWITCHES), "cs", },
- {EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_MIGRATIONS), "cpu-migrations", },
- {EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_MIGRATIONS), "migrations", },
-};
-
-#define __PERF_COUNTER_FIELD(config, name) \
- ((config & PERF_COUNTER_##name##_MASK) >> PERF_COUNTER_##name##_SHIFT)
-
-#define PERF_COUNTER_RAW(config) __PERF_COUNTER_FIELD(config, RAW)
-#define PERF_COUNTER_CONFIG(config) __PERF_COUNTER_FIELD(config, CONFIG)
-#define PERF_COUNTER_TYPE(config) __PERF_COUNTER_FIELD(config, TYPE)
-#define PERF_COUNTER_ID(config) __PERF_COUNTER_FIELD(config, EVENT)
-
-static void display_events_help(void)
-{
- unsigned int i;
- __u64 e;
-
- printf(
- " -e EVENT --event=EVENT # symbolic-name abbreviations");
-
- for (i = 0; i < ARRAY_SIZE(event_symbols); i++) {
- int type, id;
-
- e = event_symbols[i].event;
- type = PERF_COUNTER_TYPE(e);
- id = PERF_COUNTER_ID(e);
-
- printf("\n %d:%d: %-20s",
- type, id, event_symbols[i].symbol);
- }
-
- printf("\n"
- " rNNN: raw PMU events (eventsel+umask)\n\n");
-}
-
-static void display_help(void)
-{
- printf(
- "Usage: kerneltop [<options>]\n"
- " Or: kerneltop -S [<options>] COMMAND [ARGS]\n\n"
- "KernelTop Options (up to %d event types can be specified at once):\n\n",
- MAX_COUNTERS);
-
- display_events_help();
-
- printf(
- " -c CNT --count=CNT # event period to sample\n\n"
- " -C CPU --cpu=CPU # CPU (-1 for all) [default: -1]\n"
- " -p PID --pid=PID # PID of sampled task (-1 for all) [default: -1]\n\n"
- " -l # show scale factor for RR events\n"
- " -d delay --delay=<seconds> # sampling/display delay [default: 2]\n"
- " -f CNT --filter=CNT # min-event-count filter [default: 100]\n\n"
- " -r prio --realtime=<prio> # event acquisition runs with SCHED_FIFO policy\n"
- " -s symbol --symbol=<symbol> # function to be showed annotated one-shot\n"
- " -x path --vmlinux=<path> # the vmlinux binary, required for -s use\n"
- " -z --zero # zero counts after display\n"
- " -D --dump_symtab # dump symbol table to stderr on startup\n"
- " -m pages --mmap_pages=<pages> # number of mmap data pages\n"
- " -M --mmap_info # print mmap info stream\n"
- " -U --munmap_info # print munmap info stream\n"
- );
-
- exit(0);
-}
-
-static char *event_name(int ctr)
-{
- __u64 config = event_id[ctr];
- int type = PERF_COUNTER_TYPE(config);
- int id = PERF_COUNTER_ID(config);
- static char buf[32];
-
- if (PERF_COUNTER_RAW(config)) {
- sprintf(buf, "raw 0x%llx", PERF_COUNTER_CONFIG(config));
- return buf;
- }
-
- switch (type) {
- case PERF_TYPE_HARDWARE:
- if (id < PERF_HW_EVENTS_MAX)
- return hw_event_names[id];
- return "unknown-hardware";
-
- case PERF_TYPE_SOFTWARE:
- if (id < PERF_SW_EVENTS_MAX)
- return sw_event_names[id];
- return "unknown-software";
-
- default:
- break;
- }
-
- return "unknown";
-}
-
-/*
- * Each event can have multiple symbolic names.
- * Symbolic names are (almost) exactly matched.
- */
-static __u64 match_event_symbols(char *str)
-{
- __u64 config, id;
- int type;
- unsigned int i;
-
- if (sscanf(str, "r%llx", &config) == 1)
- return config | PERF_COUNTER_RAW_MASK;
-
- if (sscanf(str, "%d:%llu", &type, &id) == 2)
- return EID(type, id);
-
- for (i = 0; i < ARRAY_SIZE(event_symbols); i++) {
- if (!strncmp(str, event_symbols[i].symbol,
- strlen(event_symbols[i].symbol)))
- return event_symbols[i].event;
- }
-
- return ~0ULL;
-}
-
-static int parse_events(char *str)
-{
- __u64 config;
-
-again:
- if (nr_counters == MAX_COUNTERS)
- return -1;
-
- config = match_event_symbols(str);
- if (config == ~0ULL)
- return -1;
-
- event_id[nr_counters] = config;
- nr_counters++;
-
- str = strstr(str, ",");
- if (str) {
- str++;
- goto again;
- }
-
- return 0;
-}
-
/*
* Symbols
*/
@@ -331,7 +130,6 @@ struct sym_entry {
char *sym;
unsigned long count[MAX_COUNTERS];
int skip;
- struct source_line *source;
};

#define MAX_SYMS 100000
@@ -342,8 +140,6 @@ struct sym_entry *sym_filter_entry;

static struct sym_entry sym_table[MAX_SYMS];

-static void show_details(struct sym_entry *sym);
-
/*
* Ordering weight: count-1 * count-2 * ... / count-n
*/
@@ -419,15 +215,15 @@ static void print_sym_table(void)

printf( "], ");

- if (tid != -1)
- printf(" (tid: %d", tid);
+ if (target_pid != -1)
+ printf(" (target_pid: %d", target_pid);
else
printf(" (all");

if (profile_cpu != -1)
printf(", cpu: %d)\n", profile_cpu);
else {
- if (tid != -1)
+ if (target_pid != -1)
printf(")\n");
else
printf(", %d CPUs)\n", nr_cpus);
@@ -463,9 +259,6 @@ static void print_sym_table(void)
pcnt, tmp[i].addr, tmp[i].sym);
}

- if (sym_filter_entry)
- show_details(sym_filter_entry);
-
{
struct pollfd stdin_poll = { .fd = 0, .events = POLLIN };

@@ -628,134 +421,8 @@ static void parse_symbols(void)
}
}

-/*
- * Source lines
- */
-
-static void parse_vmlinux(char *filename)
-{
- FILE *file;
- char command[PATH_MAX*2];
- if (!filename)
- return;
-
- sprintf(command, "objdump --start-address=0x%016lx --stop-address=0x%016lx -dS %s", filter_start, filter_end, filename);
-
- file = popen(command, "r");
- if (!file)
- return;
-
- lines_tail = &lines;
- while (!feof(file)) {
- struct source_line *src;
- size_t dummy = 0;
- char *c;
-
- src = malloc(sizeof(struct source_line));
- assert(src != NULL);
- memset(src, 0, sizeof(struct source_line));
-
- if (getline(&src->line, &dummy, file) < 0)
- break;
- if (!src->line)
- break;
-
- c = strchr(src->line, '\n');
- if (c)
- *c = 0;
-
- src->next = NULL;
- *lines_tail = src;
- lines_tail = &src->next;
-
- if (strlen(src->line)>8 && src->line[8] == ':')
- src->EIP = strtoull(src->line, NULL, 16);
- if (strlen(src->line)>8 && src->line[16] == ':')
- src->EIP = strtoull(src->line, NULL, 16);
- }
- pclose(file);
-}
-
-static void record_precise_ip(uint64_t ip)
-{
- struct source_line *line;
-
- for (line = lines; line; line = line->next) {
- if (line->EIP == ip)
- line->count++;
- if (line->EIP > ip)
- break;
- }
-}
-
-static void lookup_sym_in_vmlinux(struct sym_entry *sym)
-{
- struct source_line *line;
- char pattern[PATH_MAX];
- sprintf(pattern, "<%s>:", sym->sym);
-
- for (line = lines; line; line = line->next) {
- if (strstr(line->line, pattern)) {
- sym->source = line;
- break;
- }
- }
-}
-
-static void show_lines(struct source_line *line_queue, int line_queue_count)
-{
- int i;
- struct source_line *line;
-
- line = line_queue;
- for (i = 0; i < line_queue_count; i++) {
- printf("%8li\t%s\n", line->count, line->line);
- line = line->next;
- }
-}
-
#define TRACE_COUNT 3

-static void show_details(struct sym_entry *sym)
-{
- struct source_line *line;
- struct source_line *line_queue = NULL;
- int displayed = 0;
- int line_queue_count = 0;
-
- if (!sym->source)
- lookup_sym_in_vmlinux(sym);
- if (!sym->source)
- return;
-
- printf("Showing details for %s\n", sym->sym);
-
- line = sym->source;
- while (line) {
- if (displayed && strstr(line->line, ">:"))
- break;
-
- if (!line_queue_count)
- line_queue = line;
- line_queue_count ++;
-
- if (line->count >= count_filter) {
- show_lines(line_queue, line_queue_count);
- line_queue_count = 0;
- line_queue = NULL;
- } else if (line_queue_count > TRACE_COUNT) {
- line_queue = line_queue->next;
- line_queue_count --;
- }
-
- line->count = 0;
- displayed++;
- if (displayed > 300)
- break;
- line = line->next;
- }
-}
-
/*
* Binary search in the histogram table and record the hit:
*/
@@ -764,8 +431,6 @@ static void record_ip(uint64_t ip, int counter)
int left_idx, middle_idx, right_idx, idx;
unsigned long left, middle, right;

- record_precise_ip(ip);
-
left_idx = 0;
right_idx = sym_table_count-1;
assert(ip <= max_ip && ip >= min_ip);
@@ -822,97 +487,6 @@ static void process_event(uint64_t ip, int counter)
record_ip(ip, counter);
}

-static void process_options(int argc, char **argv)
-{
- int error = 0, counter;
-
- for (;;) {
- int option_index = 0;
- /** Options for getopt */
- static struct option long_options[] = {
- {"count", required_argument, NULL, 'c'},
- {"cpu", required_argument, NULL, 'C'},
- {"delay", required_argument, NULL, 'd'},
- {"dump_symtab", no_argument, NULL, 'D'},
- {"event", required_argument, NULL, 'e'},
- {"filter", required_argument, NULL, 'f'},
- {"group", required_argument, NULL, 'g'},
- {"help", no_argument, NULL, 'h'},
- {"nmi", required_argument, NULL, 'n'},
- {"mmap_info", no_argument, NULL, 'M'},
- {"mmap_pages", required_argument, NULL, 'm'},
- {"munmap_info", no_argument, NULL, 'U'},
- {"pid", required_argument, NULL, 'p'},
- {"realtime", required_argument, NULL, 'r'},
- {"scale", no_argument, NULL, 'l'},
- {"symbol", required_argument, NULL, 's'},
- {"stat", no_argument, NULL, 'S'},
- {"vmlinux", required_argument, NULL, 'x'},
- {"zero", no_argument, NULL, 'z'},
- {"freq", required_argument, NULL, 'F'},
- {NULL, 0, NULL, 0 }
- };
- int c = getopt_long(argc, argv, "+:ac:C:d:De:f:g:hln:m:p:r:s:Sx:zMUF:",
- long_options, &option_index);
- if (c == -1)
- break;
-
- switch (c) {
- case 'a': system_wide = 1; break;
- case 'c': default_interval = atoi(optarg); break;
- case 'C':
- /* CPU and PID are mutually exclusive */
- if (tid != -1) {
- printf("WARNING: CPU switch overriding PID\n");
- sleep(1);
- tid = -1;
- }
- profile_cpu = atoi(optarg); break;
- case 'd': delay_secs = atoi(optarg); break;
- case 'D': dump_symtab = 1; break;
-
- case 'e': error = parse_events(optarg); break;
-
- case 'f': count_filter = atoi(optarg); break;
- case 'g': group = atoi(optarg); break;
- case 'h': display_help(); break;
- case 'l': scale = 1; break;
- case 'n': nmi = atoi(optarg); break;
- case 'p':
- /* CPU and PID are mutually exclusive */
- if (profile_cpu != -1) {
- printf("WARNING: PID switch overriding CPU\n");
- sleep(1);
- profile_cpu = -1;
- }
- tid = atoi(optarg); break;
- case 'r': realtime_prio = atoi(optarg); break;
- case 's': sym_filter = strdup(optarg); break;
- case 'x': vmlinux = strdup(optarg); break;
- case 'z': zero = 1; break;
- case 'm': mmap_pages = atoi(optarg); break;
- case 'M': use_mmap = 1; break;
- case 'U': use_munmap = 1; break;
- case 'F': freq = 1; default_interval = atoi(optarg); break;
- default: error = 1; break;
- }
- }
- if (error)
- display_help();
-
- if (!nr_counters) {
- nr_counters = 1;
- event_id[0] = 0;
- }
-
- for (counter = 0; counter < nr_counters; counter++) {
- if (event_count[counter])
- continue;
-
- event_count[counter] = default_interval;
- }
-}
-
struct mmap_data {
int counter;
void *base;
@@ -973,11 +547,11 @@ static void mmap_read(struct mmap_data *md)
struct ip_event {
struct perf_event_header header;
__u64 ip;
- __u32 pid, tid;
+ __u32 pid, target_pid;
};
struct mmap_event {
struct perf_event_header header;
- __u32 pid, tid;
+ __u32 pid, target_pid;
__u64 start;
__u64 len;
__u64 pgoff;
@@ -1043,7 +617,7 @@ static void mmap_read(struct mmap_data *md)
static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];

-int cmd_top(int argc, char **argv, const char *prefix)
+static int __cmd_top(void)
{
struct perf_counter_hw_event hw_event;
pthread_t thread;
@@ -1051,27 +625,12 @@ int cmd_top(int argc, char **argv, const char *prefix)
unsigned int cpu;
int ret;

- page_size = sysconf(_SC_PAGE_SIZE);
-
- process_options(argc, argv);
-
- nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
- assert(nr_cpus <= MAX_NR_CPUS);
- assert(nr_cpus >= 0);
-
- if (tid != -1 || profile_cpu != -1)
- nr_cpus = 1;
-
- parse_symbols();
- if (vmlinux && sym_filter_entry)
- parse_vmlinux(vmlinux);
-
for (i = 0; i < nr_cpus; i++) {
group_fd = -1;
for (counter = 0; counter < nr_counters; counter++) {

cpu = profile_cpu;
- if (tid == -1 && profile_cpu == -1)
+ if (target_pid == -1 && profile_cpu == -1)
cpu = i;

memset(&hw_event, 0, sizeof(hw_event));
@@ -1083,7 +642,7 @@ int cmd_top(int argc, char **argv, const char *prefix)
hw_event.munmap = use_munmap;
hw_event.freq = freq;

- fd[i][counter] = sys_perf_counter_open(&hw_event, tid, cpu, group_fd, 0);
+ fd[i][counter] = sys_perf_counter_open(&hw_event, target_pid, cpu, group_fd, 0);
if (fd[i][counter] < 0) {
int err = errno;
printf("kerneltop error: syscall returned with %d (%s)\n",
@@ -1147,3 +706,95 @@ int cmd_top(int argc, char **argv, const char *prefix)

return 0;
}
+
+static const char * const top_usage[] = {
+ "perf top [<options>]",
+ NULL
+};
+
+static char events_help_msg[EVENTS_HELP_MAX];
+
+static const struct option options[] = {
+ OPT_CALLBACK('e', "event", NULL, "event",
+ events_help_msg, parse_events),
+ OPT_INTEGER('c', "count", &default_interval,
+ "event period to sample"),
+ OPT_INTEGER('p', "pid", &target_pid,
+ "profile events on existing pid"),
+ OPT_BOOLEAN('a', "all-cpus", &system_wide,
+ "system-wide collection from all CPUs"),
+ OPT_INTEGER('C', "CPU", &profile_cpu,
+ "CPU to profile on"),
+ OPT_INTEGER('m', "mmap-pages", &mmap_pages,
+ "number of mmap data pages"),
+ OPT_INTEGER('r', "realtime", &realtime_prio,
+ "collect data with this RT SCHED_FIFO priority"),
+ OPT_INTEGER('d', "delay", &realtime_prio,
+ "number of seconds to delay between refreshes"),
+ OPT_BOOLEAN('D', "dump-symtab", &dump_symtab,
+ "dump the symbol table used for profiling"),
+ OPT_INTEGER('f', "--count-filter", &count_filter,
+ "only display functions with more events than this"),
+ OPT_BOOLEAN('g', "group", &group,
+ "put the counters into a counter group"),
+ OPT_STRING('s', "sym-filter", &sym_filter, "pattern",
+ "only display symbols matchig this pattern"),
+ OPT_BOOLEAN('z', "zero", &group,
+ "zero history across updates"),
+ OPT_BOOLEAN('M', "use-mmap", &use_mmap,
+ "track mmap events"),
+ OPT_BOOLEAN('U', "use-munmap", &use_munmap,
+ "track munmap events"),
+ OPT_INTEGER('F', "--freq", &freq,
+ "profile at this frequency"),
+ OPT_END()
+};
+
+int cmd_top(int argc, const char **argv, const char *prefix)
+{
+ int counter;
+
+ page_size = sysconf(_SC_PAGE_SIZE);
+
+ create_events_help(events_help_msg);
+ memcpy(event_id, default_event_id, sizeof(default_event_id));
+
+ argc = parse_options(argc, argv, options, top_usage, 0);
+ if (argc)
+ usage_with_options(top_usage, options);
+
+ if (freq) {
+ default_interval = freq;
+ freq = 1;
+ }
+
+ /* CPU and PID are mutually exclusive */
+ if (target_pid != -1 && profile_cpu != -1) {
+ printf("WARNING: PID switch overriding CPU\n");
+ sleep(1);
+ profile_cpu = -1;
+ }
+
+ if (!nr_counters) {
+ nr_counters = 1;
+ event_id[0] = 0;
+ }
+
+ for (counter = 0; counter < nr_counters; counter++) {
+ if (event_count[counter])
+ continue;
+
+ event_count[counter] = default_interval;
+ }
+
+ nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+ assert(nr_cpus <= MAX_NR_CPUS);
+ assert(nr_cpus >= 0);
+
+ if (target_pid != -1 || profile_cpu != -1)
+ nr_cpus = 1;
+
+ parse_symbols();
+
+ return __cmd_top();
+}
--
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