perf tools: Introduce event selectors

Out of ad-hoc code and global arrays with hard coded sizes.

This is the first step on having a library that will be first
used on regression tests in the 'perf test' tool.

[acme@felicio linux]$ size /tmp/perf.before
   text	   data	    bss	    dec	    hex	filename
1273776	  97384	5104416	6475576	 62cf38	/tmp/perf.before
[acme@felicio linux]$ size /tmp/perf.new
   text	   data	    bss	    dec	    hex	filename
1275422	  97416	1392416	2765254	 2a31c6	/tmp/perf.new

Cc: Frederic 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: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 104 insertions, 72 deletions

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index ae15f046c405..13a836efa1e1 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -21,6 +21,7 @@
 #include "perf.h"
 
 #include "util/color.h"
+#include "util/evsel.h"
 #include "util/session.h"
 #include "util/symbol.h"
 #include "util/thread.h"
@@ -29,6 +30,7 @@
 #include "util/parse-options.h"
 #include "util/parse-events.h"
 #include "util/cpumap.h"
+#include "util/xyarray.h"
 
 #include "util/debug.h"
 
@@ -55,7 +57,7 @@
 #include <linux/unistd.h>
 #include <linux/types.h>
 
-static int                      *fd[MAX_NR_CPUS][MAX_COUNTERS];
+#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
 
 static bool                     system_wide                     =  false;
 
@@ -100,6 +102,7 @@ struct sym_entry		*sym_filter_entry		=   NULL;
 struct sym_entry                *sym_filter_entry_sched         =   NULL;
 static int                      sym_pcnt_filter                 =      5;
 static int                      sym_counter                     =      0;
+static struct perf_evsel        *sym_evsel                      =   NULL;
 static int                      display_weighted                =     -1;
 static const char               *cpu_list;
 
@@ -353,7 +356,7 @@ static void show_details(struct sym_entry *syme)
                 return;
 
         symbol = sym_entry__symbol(syme);
-        printf("Showing %s for %s\n", event_name(sym_counter), symbol->name);
+        printf("Showing %s for %s\n", event_name(sym_evsel), symbol->name);
         printf("  Events  Pcnt (>=%d%%)\n", sym_pcnt_filter);
 
         pthread_mutex_lock(&syme->src->lock);
@@ -460,7 +463,8 @@ static void rb_insert_active_sym(struct rb_root *tree, struct sym_entry *se)
 static void print_sym_table(void)
 {
         int printed = 0, j;
-        int counter, snap = !display_weighted ? sym_counter : 0;
+        struct perf_evsel *counter;
+        int snap = !display_weighted ? sym_counter : 0;
         float samples_per_sec = samples/delay_secs;
         float ksamples_per_sec = kernel_samples/delay_secs;
         float us_samples_per_sec = (us_samples)/delay_secs;
@@ -532,7 +536,9 @@ static void print_sym_table(void)
         }
 
         if (nr_counters == 1 || !display_weighted) {
-                printf("%Ld", (u64)attrs[0].sample_period);
+                struct perf_evsel *first;
+                first = list_entry(evsel_list.next, struct perf_evsel, node);
+                printf("%Ld", first->attr.sample_period);
                 if (freq)
                         printf("Hz ");
                 else
@@ -540,9 +546,9 @@ static void print_sym_table(void)
         }
 
         if (!display_weighted)
-                printf("%s", event_name(sym_counter));
-        else for (counter = 0; counter < nr_counters; counter++) {
-                if (counter)
+                printf("%s", event_name(sym_evsel));
+        else list_for_each_entry(counter, &evsel_list, node) {
+                if (counter->idx)
                         printf("/");
 
                 printf("%s", event_name(counter));
@@ -739,7 +745,7 @@ static void print_mapped_keys(void)
         fprintf(stdout, "\t[e]     display entries (lines).           \t(%d)\n", print_entries);
 
         if (nr_counters > 1)
-                fprintf(stdout, "\t[E]     active event counter.              \t(%s)\n", event_name(sym_counter));
+                fprintf(stdout, "\t[E]     active event counter.              \t(%s)\n", event_name(sym_evsel));
 
         fprintf(stdout, "\t[f]     profile display filter (count).    \t(%d)\n", count_filter);
 
@@ -826,19 +832,23 @@ static void handle_keypress(struct perf_session *session, int c)
                         break;
                 case 'E':
                         if (nr_counters > 1) {
-                                int i;
-
                                 fprintf(stderr, "\nAvailable events:");
-                                for (i = 0; i < nr_counters; i++)
-                                        fprintf(stderr, "\n\t%d %s", i, event_name(i));
+
+                                list_for_each_entry(sym_evsel, &evsel_list, node)
+                                        fprintf(stderr, "\n\t%d %s", sym_evsel->idx, event_name(sym_evsel));
 
                                 prompt_integer(&sym_counter, "Enter details event counter");
 
                                 if (sym_counter >= nr_counters) {
-                                        fprintf(stderr, "Sorry, no such event, using %s.\n", event_name(0));
+                                        sym_evsel = list_entry(evsel_list.next, struct perf_evsel, node);
                                         sym_counter = 0;
+                                        fprintf(stderr, "Sorry, no such event, using %s.\n", event_name(sym_evsel));
                                         sleep(1);
+                                        break;
                                 }
+                                list_for_each_entry(sym_evsel, &evsel_list, node)
+                                        if (sym_evsel->idx == sym_counter)
+                                                break;
                         } else sym_counter = 0;
                         break;
                 case 'f':
@@ -978,7 +988,8 @@ static int symbol_filter(struct map *map, struct symbol *sym)
 
 static void event__process_sample(const event_t *self,
                                   struct sample_data *sample,
-                                  struct perf_session *session, int counter)
+                                  struct perf_session *session,
+                                  struct perf_evsel *evsel)
 {
         u64 ip = self->ip.ip;
         struct sym_entry *syme;
@@ -1071,9 +1082,9 @@ static void event__process_sample(const event_t *self,
 
         syme = symbol__priv(al.sym);
         if (!syme->skip) {
-                syme->count[counter]++;
+                syme->count[evsel->idx]++;
                 syme->origin = origin;
-                record_precise_ip(syme, counter, ip);
+                record_precise_ip(syme, evsel->idx, ip);
                 pthread_mutex_lock(&active_symbols_lock);
                 if (list_empty(&syme->node) || !syme->node.next)
                         __list_insert_active_sym(syme);
@@ -1082,12 +1093,24 @@ static void event__process_sample(const event_t *self,
 }
 
 struct mmap_data {
-        int                     counter;
         void                    *base;
         int                     mask;
         unsigned int            prev;
 };
 
+static int perf_evsel__alloc_mmap_per_thread(struct perf_evsel *evsel,
+                                             int ncpus, int nthreads)
+{
+        evsel->priv = xyarray__new(ncpus, nthreads, sizeof(struct mmap_data));
+        return evsel->priv != NULL ? 0 : -ENOMEM;
+}
+
+static void perf_evsel__free_mmap(struct perf_evsel *evsel)
+{
+        xyarray__delete(evsel->priv);
+        evsel->priv = NULL;
+}
+
 static unsigned int mmap_read_head(struct mmap_data *md)
 {
         struct perf_event_mmap_page *pc = md->base;
@@ -1100,8 +1123,11 @@ static unsigned int mmap_read_head(struct mmap_data *md)
 }
 
 static void perf_session__mmap_read_counter(struct perf_session *self,
-                                            struct mmap_data *md)
+                                            struct perf_evsel *evsel,
+                                            int cpu, int thread_idx)
 {
+        struct xyarray *mmap_array = evsel->priv;
+        struct mmap_data *md = xyarray__entry(mmap_array, cpu, thread_idx);
         unsigned int head = mmap_read_head(md);
         unsigned int old = md->prev;
         unsigned char *data = md->base + page_size;
@@ -1155,7 +1181,7 @@ static void perf_session__mmap_read_counter(struct perf_session *self,
 
                 event__parse_sample(event, self, &sample);
                 if (event->header.type == PERF_RECORD_SAMPLE)
-                        event__process_sample(event, &sample, self, md->counter);
+                        event__process_sample(event, &sample, self, evsel);
                 else
                         event__process(event, &sample, self);
                 old += size;
@@ -1165,28 +1191,31 @@ static void perf_session__mmap_read_counter(struct perf_session *self,
 }
 
 static struct pollfd *event_array;
-static struct mmap_data *mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
 
 static void perf_session__mmap_read(struct perf_session *self)
 {
-        int i, counter, thread_index;
+        struct perf_evsel *counter;
+        int i, thread_index;
 
         for (i = 0; i < nr_cpus; i++) {
-                for (counter = 0; counter < nr_counters; counter++)
+                list_for_each_entry(counter, &evsel_list, node) {
                         for (thread_index = 0;
                                 thread_index < thread_num;
                                 thread_index++) {
                                 perf_session__mmap_read_counter(self,
-                                        &mmap_array[i][counter][thread_index]);
+                                        counter, i, thread_index);
                         }
+                }
         }
 }
 
 int nr_poll;
 int group_fd;
 
-static void start_counter(int i, int counter)
+static void start_counter(int i, struct perf_evsel *evsel)
 {
+        struct xyarray *mmap_array = evsel->priv;
+        struct mmap_data *mm;
         struct perf_event_attr *attr;
         int cpu = -1;
         int thread_index;
@@ -1194,7 +1223,7 @@ static void start_counter(int i, int counter)
         if (target_tid == -1)
                 cpu = cpumap[i];
 
-        attr = attrs + counter;
+        attr = &evsel->attr;
 
         attr->sample_type       = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
 
@@ -1209,10 +1238,10 @@ static void start_counter(int i, int counter)
 
         for (thread_index = 0; thread_index < thread_num; thread_index++) {
 try_again:
-                fd[i][counter][thread_index] = sys_perf_event_open(attr,
+                FD(evsel, i, thread_index) = sys_perf_event_open(attr,
                                 all_tids[thread_index], cpu, group_fd, 0);
 
-                if (fd[i][counter][thread_index] < 0) {
+                if (FD(evsel, i, thread_index) < 0) {
                         int err = errno;
 
                         if (err == EPERM || err == EACCES)
@@ -1236,29 +1265,29 @@ try_again:
                         }
                         printf("\n");
                         error("sys_perf_event_open() syscall returned with %d (%s).  /bin/dmesg may provide additional information.\n",
-                                        fd[i][counter][thread_index], strerror(err));
+                                        FD(evsel, i, thread_index), strerror(err));
                         die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
                         exit(-1);
                 }
-                assert(fd[i][counter][thread_index] >= 0);
-                fcntl(fd[i][counter][thread_index], F_SETFL, O_NONBLOCK);
+                assert(FD(evsel, i, thread_index) >= 0);
+                fcntl(FD(evsel, i, thread_index), F_SETFL, O_NONBLOCK);
 
                 /*
                  * First counter acts as the group leader:
                  */
                 if (group && group_fd == -1)
-                        group_fd = fd[i][counter][thread_index];
+                        group_fd = FD(evsel, i, thread_index);
 
-                event_array[nr_poll].fd = fd[i][counter][thread_index];
+                event_array[nr_poll].fd = FD(evsel, i, thread_index);
                 event_array[nr_poll].events = POLLIN;
                 nr_poll++;
 
-                mmap_array[i][counter][thread_index].counter = counter;
-                mmap_array[i][counter][thread_index].prev = 0;
-                mmap_array[i][counter][thread_index].mask = mmap_pages*page_size - 1;
-                mmap_array[i][counter][thread_index].base = mmap(NULL, (mmap_pages+1)*page_size,
-                                PROT_READ, MAP_SHARED, fd[i][counter][thread_index], 0);
-                if (mmap_array[i][counter][thread_index].base == MAP_FAILED)
+                mm = xyarray__entry(mmap_array, i, thread_index);
+                mm->prev = 0;
+                mm->mask = mmap_pages*page_size - 1;
+                mm->base = mmap(NULL, (mmap_pages+1)*page_size,
+                                PROT_READ, MAP_SHARED, FD(evsel, i, thread_index), 0);
+                if (mm->base == MAP_FAILED)
                         die("failed to mmap with %d (%s)\n", errno, strerror(errno));
         }
 }
@@ -1266,8 +1295,8 @@ try_again:
 static int __cmd_top(void)
 {
         pthread_t thread;
-        int i, counter;
-        int ret;
+        struct perf_evsel *counter;
+        int i, ret;
         /*
          * FIXME: perf_session__new should allow passing a O_MMAP, so that all this
          * mmap reading, etc is encapsulated in it. Use O_WRONLY for now.
@@ -1283,7 +1312,7 @@ static int __cmd_top(void)
 
         for (i = 0; i < nr_cpus; i++) {
                 group_fd = -1;
-                for (counter = 0; counter < nr_counters; counter++)
+                list_for_each_entry(counter, &evsel_list, node)
                         start_counter(i, counter);
         }
 
@@ -1372,8 +1401,8 @@ static const struct option options[] = {
 
 int cmd_top(int argc, const char **argv, const char *prefix __used)
 {
-        int counter;
-        int i,j;
+        struct perf_evsel *pos;
+        int status = -ENOMEM;
 
         page_size = sysconf(_SC_PAGE_SIZE);
 
@@ -1398,15 +1427,6 @@ int cmd_top(int argc, const char **argv, const char *prefix __used)
                 thread_num = 1;
         }
 
-        for (i = 0; i < MAX_NR_CPUS; i++) {
-                for (j = 0; j < MAX_COUNTERS; j++) {
-                        fd[i][j] = malloc(sizeof(int)*thread_num);
-                        mmap_array[i][j] = zalloc(
-                                sizeof(struct mmap_data)*thread_num);
-                        if (!fd[i][j] || !mmap_array[i][j])
-                                return -ENOMEM;
-                }
-        }
         event_array = malloc(
                 sizeof(struct pollfd)*MAX_NR_CPUS*MAX_COUNTERS*thread_num);
         if (!event_array)
@@ -1419,15 +1439,10 @@ int cmd_top(int argc, const char **argv, const char *prefix __used)
                 cpu_list = NULL;
         }
 
-        if (!nr_counters)
-                nr_counters = 1;
-
-        symbol_conf.priv_size = (sizeof(struct sym_entry) +
-                                 (nr_counters + 1) * sizeof(unsigned long));
-
-        symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
-        if (symbol__init() < 0)
-                return -1;
+        if (!nr_counters && perf_evsel_list__create_default() < 0) {
+                pr_err("Not enough memory for event selector list\n");
+                return -ENOMEM;
+        }
 
         if (delay_secs < 1)
                 delay_secs = 1;
@@ -1444,16 +1459,6 @@ int cmd_top(int argc, const char **argv, const char *prefix __used)
                 exit(EXIT_FAILURE);
         }
 
-        /*
-         * Fill in the ones not specifically initialized via -c:
-         */
-        for (counter = 0; counter < nr_counters; counter++) {
-                if (attrs[counter].sample_period)
-                        continue;
-
-                attrs[counter].sample_period = default_interval;
-        }
-
         if (target_tid != -1)
                 nr_cpus = 1;
         else
@@ -1462,11 +1467,38 @@ int cmd_top(int argc, const char **argv, const char *prefix __used)
         if (nr_cpus < 1)
                 usage_with_options(top_usage, options);
 
+        list_for_each_entry(pos, &evsel_list, node) {
+                if (perf_evsel__alloc_mmap_per_thread(pos, nr_cpus, thread_num) < 0 ||
+                    perf_evsel__alloc_fd(pos, nr_cpus, thread_num) < 0)
+                        goto out_free_fd;
+                /*
+                 * Fill in the ones not specifically initialized via -c:
+                 */
+                if (pos->attr.sample_period)
+                        continue;
+
+                pos->attr.sample_period = default_interval;
+        }
+
+        symbol_conf.priv_size = (sizeof(struct sym_entry) +
+                                 (nr_counters + 1) * sizeof(unsigned long));
+
+        symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
+        if (symbol__init() < 0)
+                return -1;
+
         get_term_dimensions(&winsize);
         if (print_entries == 0) {
                 update_print_entries(&winsize);
                 signal(SIGWINCH, sig_winch_handler);
         }
 
-        return __cmd_top();
+        status = __cmd_top();
+out_free_fd:
+        list_for_each_entry(pos, &evsel_list, node) {
+                perf_evsel__free_fd(pos);
+                perf_evsel__free_mmap(pos);
+        }
+
+        return status;
 }