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-rw-r--r--tools/perf/Documentation/perf-record.txt3
-rw-r--r--tools/perf/Makefile2
-rw-r--r--tools/perf/arch/s390/Makefile4
-rw-r--r--tools/perf/arch/s390/util/dwarf-regs.c22
-rw-r--r--tools/perf/builtin-record.c9
-rw-r--r--tools/perf/builtin-sched.c23
-rw-r--r--tools/perf/builtin-stat.c6
-rw-r--r--tools/perf/builtin-test.c116
-rw-r--r--tools/perf/builtin-top.c3
-rw-r--r--tools/perf/perf.c2
-rw-r--r--tools/perf/util/evsel.c87
-rw-r--r--tools/perf/util/evsel.h2
-rw-r--r--tools/perf/util/parse-events.c74
-rw-r--r--tools/perf/util/session.c2
14 files changed, 266 insertions, 89 deletions
diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index 52462ae2645..e032716c839 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -61,6 +61,9 @@ OPTIONS
-r::
--realtime=::
Collect data with this RT SCHED_FIFO priority.
+-D::
+--no-delay::
+ Collect data without buffering.
-A::
--append::
Append to the output file to do incremental profiling.
diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 1b9b13ee2a7..2b5387d53ba 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -227,7 +227,7 @@ ifndef PERF_DEBUG
CFLAGS_OPTIMIZE = -O6
endif
-CFLAGS = -ggdb3 -Wall -Wextra -std=gnu99 -Werror $(CFLAGS_OPTIMIZE) -D_FORTIFY_SOURCE=2 $(EXTRA_WARNINGS) $(EXTRA_CFLAGS)
+CFLAGS = -fno-omit-frame-pointer -ggdb3 -Wall -Wextra -std=gnu99 -Werror $(CFLAGS_OPTIMIZE) -D_FORTIFY_SOURCE=2 $(EXTRA_WARNINGS) $(EXTRA_CFLAGS)
EXTLIBS = -lpthread -lrt -lelf -lm
ALL_CFLAGS = $(CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
ALL_LDFLAGS = $(LDFLAGS)
diff --git a/tools/perf/arch/s390/Makefile b/tools/perf/arch/s390/Makefile
new file mode 100644
index 00000000000..15130b50dfe
--- /dev/null
+++ b/tools/perf/arch/s390/Makefile
@@ -0,0 +1,4 @@
+ifndef NO_DWARF
+PERF_HAVE_DWARF_REGS := 1
+LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/dwarf-regs.o
+endif
diff --git a/tools/perf/arch/s390/util/dwarf-regs.c b/tools/perf/arch/s390/util/dwarf-regs.c
new file mode 100644
index 00000000000..e19653e025f
--- /dev/null
+++ b/tools/perf/arch/s390/util/dwarf-regs.c
@@ -0,0 +1,22 @@
+/*
+ * Mapping of DWARF debug register numbers into register names.
+ *
+ * Copyright IBM Corp. 2010
+ * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
+ *
+ */
+
+#include <libio.h>
+#include <dwarf-regs.h>
+
+#define NUM_GPRS 16
+
+static const char *gpr_names[NUM_GPRS] = {
+ "%r0", "%r1", "%r2", "%r3", "%r4", "%r5", "%r6", "%r7",
+ "%r8", "%r9", "%r10", "%r11", "%r12", "%r13", "%r14", "%r15",
+};
+
+const char *get_arch_regstr(unsigned int n)
+{
+ return (n >= NUM_GPRS) ? NULL : gpr_names[n];
+}
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 7bc04903548..df6064ad9bf 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -49,6 +49,7 @@ static int pipe_output = 0;
static const char *output_name = "perf.data";
static int group = 0;
static int realtime_prio = 0;
+static bool nodelay = false;
static bool raw_samples = false;
static bool sample_id_all_avail = true;
static bool system_wide = false;
@@ -307,6 +308,11 @@ static void create_counter(struct perf_evsel *evsel, int cpu)
attr->sample_type |= PERF_SAMPLE_CPU;
}
+ if (nodelay) {
+ attr->watermark = 0;
+ attr->wakeup_events = 1;
+ }
+
attr->mmap = track;
attr->comm = track;
attr->inherit = !no_inherit;
@@ -477,6 +483,7 @@ static void atexit_header(void)
process_buildids();
perf_header__write(&session->header, output, true);
perf_session__delete(session);
+ perf_evsel_list__delete();
symbol__exit();
}
}
@@ -842,6 +849,8 @@ const struct option record_options[] = {
"record events on existing thread id"),
OPT_INTEGER('r', "realtime", &realtime_prio,
"collect data with this RT SCHED_FIFO priority"),
+ OPT_BOOLEAN('D', "no-delay", &nodelay,
+ "collect data without buffering"),
OPT_BOOLEAN('R', "raw-samples", &raw_samples,
"collect raw sample records from all opened counters"),
OPT_BOOLEAN('a', "all-cpus", &system_wide,
diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index 7a4ebeb8b01..29e7ffd8569 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -489,7 +489,8 @@ static void create_tasks(void)
err = pthread_attr_init(&attr);
BUG_ON(err);
- err = pthread_attr_setstacksize(&attr, (size_t)(16*1024));
+ err = pthread_attr_setstacksize(&attr,
+ (size_t) max(16 * 1024, PTHREAD_STACK_MIN));
BUG_ON(err);
err = pthread_mutex_lock(&start_work_mutex);
BUG_ON(err);
@@ -1842,15 +1843,15 @@ static const char *record_args[] = {
"-f",
"-m", "1024",
"-c", "1",
- "-e", "sched:sched_switch:r",
- "-e", "sched:sched_stat_wait:r",
- "-e", "sched:sched_stat_sleep:r",
- "-e", "sched:sched_stat_iowait:r",
- "-e", "sched:sched_stat_runtime:r",
- "-e", "sched:sched_process_exit:r",
- "-e", "sched:sched_process_fork:r",
- "-e", "sched:sched_wakeup:r",
- "-e", "sched:sched_migrate_task:r",
+ "-e", "sched:sched_switch",
+ "-e", "sched:sched_stat_wait",
+ "-e", "sched:sched_stat_sleep",
+ "-e", "sched:sched_stat_iowait",
+ "-e", "sched:sched_stat_runtime",
+ "-e", "sched:sched_process_exit",
+ "-e", "sched:sched_process_fork",
+ "-e", "sched:sched_wakeup",
+ "-e", "sched:sched_migrate_task",
};
static int __cmd_record(int argc, const char **argv)
@@ -1861,7 +1862,7 @@ static int __cmd_record(int argc, const char **argv)
rec_argc = ARRAY_SIZE(record_args) + argc - 1;
rec_argv = calloc(rec_argc + 1, sizeof(char *));
- if (rec_argv)
+ if (rec_argv == NULL)
return -ENOMEM;
for (i = 0; i < ARRAY_SIZE(record_args); i++)
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 02b2d8013a6..0ff11d9b13b 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -316,6 +316,8 @@ static int run_perf_stat(int argc __used, const char **argv)
"\t Consider tweaking"
" /proc/sys/kernel/perf_event_paranoid or running as root.",
system_wide ? "system-wide " : "");
+ } else if (errno == ENOENT) {
+ error("%s event is not supported. ", event_name(counter));
} else {
error("open_counter returned with %d (%s). "
"/bin/dmesg may provide additional information.\n",
@@ -683,8 +685,7 @@ int cmd_stat(int argc, const char **argv, const char *prefix __used)
nr_counters = ARRAY_SIZE(default_attrs);
for (c = 0; c < ARRAY_SIZE(default_attrs); ++c) {
- pos = perf_evsel__new(default_attrs[c].type,
- default_attrs[c].config,
+ pos = perf_evsel__new(&default_attrs[c],
nr_counters);
if (pos == NULL)
goto out;
@@ -742,6 +743,7 @@ int cmd_stat(int argc, const char **argv, const char *prefix __used)
out_free_fd:
list_for_each_entry(pos, &evsel_list, node)
perf_evsel__free_stat_priv(pos);
+ perf_evsel_list__delete();
out:
thread_map__delete(threads);
threads = NULL;
diff --git a/tools/perf/builtin-test.c b/tools/perf/builtin-test.c
index 1c984342a57..ed5696198d3 100644
--- a/tools/perf/builtin-test.c
+++ b/tools/perf/builtin-test.c
@@ -234,6 +234,7 @@ out:
return err;
}
+#include "util/cpumap.h"
#include "util/evsel.h"
#include <sys/types.h>
@@ -264,6 +265,7 @@ static int test__open_syscall_event(void)
int err = -1, fd;
struct thread_map *threads;
struct perf_evsel *evsel;
+ struct perf_event_attr attr;
unsigned int nr_open_calls = 111, i;
int id = trace_event__id("sys_enter_open");
@@ -278,7 +280,10 @@ static int test__open_syscall_event(void)
return -1;
}
- evsel = perf_evsel__new(PERF_TYPE_TRACEPOINT, id, 0);
+ memset(&attr, 0, sizeof(attr));
+ attr.type = PERF_TYPE_TRACEPOINT;
+ attr.config = id;
+ evsel = perf_evsel__new(&attr, 0);
if (evsel == NULL) {
pr_debug("perf_evsel__new\n");
goto out_thread_map_delete;
@@ -317,6 +322,111 @@ out_thread_map_delete:
return err;
}
+#include <sched.h>
+
+static int test__open_syscall_event_on_all_cpus(void)
+{
+ int err = -1, fd, cpu;
+ struct thread_map *threads;
+ struct cpu_map *cpus;
+ struct perf_evsel *evsel;
+ struct perf_event_attr attr;
+ unsigned int nr_open_calls = 111, i;
+ cpu_set_t *cpu_set;
+ size_t cpu_set_size;
+ int id = trace_event__id("sys_enter_open");
+
+ if (id < 0) {
+ pr_debug("is debugfs mounted on /sys/kernel/debug?\n");
+ return -1;
+ }
+
+ threads = thread_map__new(-1, getpid());
+ if (threads == NULL) {
+ pr_debug("thread_map__new\n");
+ return -1;
+ }
+
+ cpus = cpu_map__new(NULL);
+ if (threads == NULL) {
+ pr_debug("thread_map__new\n");
+ return -1;
+ }
+
+ cpu_set = CPU_ALLOC(cpus->nr);
+
+ if (cpu_set == NULL)
+ goto out_thread_map_delete;
+
+ cpu_set_size = CPU_ALLOC_SIZE(cpus->nr);
+ CPU_ZERO_S(cpu_set_size, cpu_set);
+
+ memset(&attr, 0, sizeof(attr));
+ attr.type = PERF_TYPE_TRACEPOINT;
+ attr.config = id;
+ evsel = perf_evsel__new(&attr, 0);
+ if (evsel == NULL) {
+ pr_debug("perf_evsel__new\n");
+ goto out_cpu_free;
+ }
+
+ if (perf_evsel__open(evsel, cpus, threads) < 0) {
+ pr_debug("failed to open counter: %s, "
+ "tweak /proc/sys/kernel/perf_event_paranoid?\n",
+ strerror(errno));
+ goto out_evsel_delete;
+ }
+
+ for (cpu = 0; cpu < cpus->nr; ++cpu) {
+ unsigned int ncalls = nr_open_calls + cpu;
+
+ CPU_SET(cpu, cpu_set);
+ sched_setaffinity(0, cpu_set_size, cpu_set);
+ for (i = 0; i < ncalls; ++i) {
+ fd = open("/etc/passwd", O_RDONLY);
+ close(fd);
+ }
+ CPU_CLR(cpu, cpu_set);
+ }
+
+ /*
+ * Here we need to explicitely preallocate the counts, as if
+ * we use the auto allocation it will allocate just for 1 cpu,
+ * as we start by cpu 0.
+ */
+ if (perf_evsel__alloc_counts(evsel, cpus->nr) < 0) {
+ pr_debug("perf_evsel__alloc_counts(ncpus=%d)\n", cpus->nr);
+ goto out_close_fd;
+ }
+
+ for (cpu = 0; cpu < cpus->nr; ++cpu) {
+ unsigned int expected;
+
+ if (perf_evsel__read_on_cpu(evsel, cpu, 0) < 0) {
+ pr_debug("perf_evsel__open_read_on_cpu\n");
+ goto out_close_fd;
+ }
+
+ expected = nr_open_calls + cpu;
+ if (evsel->counts->cpu[cpu].val != expected) {
+ pr_debug("perf_evsel__read_on_cpu: expected to intercept %d calls on cpu %d, got %Ld\n",
+ expected, cpu, evsel->counts->cpu[cpu].val);
+ goto out_close_fd;
+ }
+ }
+
+ err = 0;
+out_close_fd:
+ perf_evsel__close_fd(evsel, 1, threads->nr);
+out_evsel_delete:
+ perf_evsel__delete(evsel);
+out_cpu_free:
+ CPU_FREE(cpu_set);
+out_thread_map_delete:
+ thread_map__delete(threads);
+ return err;
+}
+
static struct test {
const char *desc;
int (*func)(void);
@@ -330,6 +440,10 @@ static struct test {
.func = test__open_syscall_event,
},
{
+ .desc = "detect open syscall event on all cpus",
+ .func = test__open_syscall_event_on_all_cpus,
+ },
+ {
.func = NULL,
},
};
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 1e67ab9c7eb..05344c6210a 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -1471,6 +1471,8 @@ int cmd_top(int argc, const char **argv, const char *prefix __used)
pos->attr.sample_period = default_interval;
}
+ sym_evsel = list_entry(evsel_list.next, struct perf_evsel, node);
+
symbol_conf.priv_size = (sizeof(struct sym_entry) +
(nr_counters + 1) * sizeof(unsigned long));
@@ -1488,6 +1490,7 @@ int cmd_top(int argc, const char **argv, const char *prefix __used)
out_free_fd:
list_for_each_entry(pos, &evsel_list, node)
perf_evsel__free_mmap(pos);
+ perf_evsel_list__delete();
return status;
}
diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 5b1ecd66bb3..595d0f4a710 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -286,8 +286,6 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
status = p->fn(argc, argv, prefix);
exit_browser(status);
- perf_evsel_list__delete();
-
if (status)
return status & 0xff;
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index c95267e63c5..f5cfed60af9 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -6,14 +6,13 @@
#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
-struct perf_evsel *perf_evsel__new(u32 type, u64 config, int idx)
+struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr, int idx)
{
struct perf_evsel *evsel = zalloc(sizeof(*evsel));
if (evsel != NULL) {
evsel->idx = idx;
- evsel->attr.type = type;
- evsel->attr.config = config;
+ evsel->attr = *attr;
INIT_LIST_HEAD(&evsel->node);
}
@@ -128,59 +127,75 @@ int __perf_evsel__read(struct perf_evsel *evsel,
return 0;
}
-int perf_evsel__open_per_cpu(struct perf_evsel *evsel, struct cpu_map *cpus)
+static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
+ struct thread_map *threads)
{
- int cpu;
+ int cpu, thread;
- if (evsel->fd == NULL && perf_evsel__alloc_fd(evsel, cpus->nr, 1) < 0)
+ if (evsel->fd == NULL &&
+ perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
return -1;
for (cpu = 0; cpu < cpus->nr; cpu++) {
- FD(evsel, cpu, 0) = sys_perf_event_open(&evsel->attr, -1,
- cpus->map[cpu], -1, 0);
- if (FD(evsel, cpu, 0) < 0)
- goto out_close;
+ for (thread = 0; thread < threads->nr; thread++) {
+ FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
+ threads->map[thread],
+ cpus->map[cpu], -1, 0);
+ if (FD(evsel, cpu, thread) < 0)
+ goto out_close;
+ }
}
return 0;
out_close:
- while (--cpu >= 0) {
- close(FD(evsel, cpu, 0));
- FD(evsel, cpu, 0) = -1;
- }
+ do {
+ while (--thread >= 0) {
+ close(FD(evsel, cpu, thread));
+ FD(evsel, cpu, thread) = -1;
+ }
+ thread = threads->nr;
+ } while (--cpu >= 0);
return -1;
}
-int perf_evsel__open_per_thread(struct perf_evsel *evsel, struct thread_map *threads)
+static struct {
+ struct cpu_map map;
+ int cpus[1];
+} empty_cpu_map = {
+ .map.nr = 1,
+ .cpus = { -1, },
+};
+
+static struct {
+ struct thread_map map;
+ int threads[1];
+} empty_thread_map = {
+ .map.nr = 1,
+ .threads = { -1, },
+};
+
+int perf_evsel__open(struct perf_evsel *evsel,
+ struct cpu_map *cpus, struct thread_map *threads)
{
- int thread;
-
- if (evsel->fd == NULL && perf_evsel__alloc_fd(evsel, 1, threads->nr))
- return -1;
- for (thread = 0; thread < threads->nr; thread++) {
- FD(evsel, 0, thread) = sys_perf_event_open(&evsel->attr,
- threads->map[thread], -1, -1, 0);
- if (FD(evsel, 0, thread) < 0)
- goto out_close;
+ if (cpus == NULL) {
+ /* Work around old compiler warnings about strict aliasing */
+ cpus = &empty_cpu_map.map;
}
- return 0;
+ if (threads == NULL)
+ threads = &empty_thread_map.map;
-out_close:
- while (--thread >= 0) {
- close(FD(evsel, 0, thread));
- FD(evsel, 0, thread) = -1;
- }
- return -1;
+ return __perf_evsel__open(evsel, cpus, threads);
}
-int perf_evsel__open(struct perf_evsel *evsel,
- struct cpu_map *cpus, struct thread_map *threads)
+int perf_evsel__open_per_cpu(struct perf_evsel *evsel, struct cpu_map *cpus)
{
- if (threads == NULL)
- return perf_evsel__open_per_cpu(evsel, cpus);
+ return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
+}
- return perf_evsel__open_per_thread(evsel, threads);
+int perf_evsel__open_per_thread(struct perf_evsel *evsel, struct thread_map *threads)
+{
+ return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
}
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index a0ccd69c3fc..b2d755fe88a 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -37,7 +37,7 @@ struct perf_evsel {
struct cpu_map;
struct thread_map;
-struct perf_evsel *perf_evsel__new(u32 type, u64 config, int idx);
+struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr, int idx);
void perf_evsel__delete(struct perf_evsel *evsel);
int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads);
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 649083f27e0..5cb6f4bde90 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -490,6 +490,31 @@ parse_multiple_tracepoint_event(char *sys_name, const char *evt_exp,
return EVT_HANDLED_ALL;
}
+static int store_event_type(const char *orgname)
+{
+ char filename[PATH_MAX], *c;
+ FILE *file;
+ int id, n;
+
+ sprintf(filename, "%s/", debugfs_path);
+ strncat(filename, orgname, strlen(orgname));
+ strcat(filename, "/id");
+
+ c = strchr(filename, ':');
+ if (c)
+ *c = '/';
+
+ file = fopen(filename, "r");
+ if (!file)
+ return 0;
+ n = fscanf(file, "%i", &id);
+ fclose(file);
+ if (n < 1) {
+ pr_err("cannot store event ID\n");
+ return -EINVAL;
+ }
+ return perf_header__push_event(id, orgname);
+}
static enum event_result parse_tracepoint_event(const char **strp,
struct perf_event_attr *attr)
@@ -533,9 +558,13 @@ static enum event_result parse_tracepoint_event(const char **strp,
*strp += strlen(sys_name) + evt_length;
return parse_multiple_tracepoint_event(sys_name, evt_name,
flags);
- } else
+ } else {
+ if (store_event_type(evt_name) < 0)
+ return EVT_FAILED;
+
return parse_single_tracepoint_event(sys_name, evt_name,
evt_length, attr, strp);
+ }
}
static enum event_result
@@ -778,41 +807,11 @@ modifier:
return ret;
}
-static int store_event_type(const char *orgname)
-{
- char filename[PATH_MAX], *c;
- FILE *file;
- int id, n;
-
- sprintf(filename, "%s/", debugfs_path);
- strncat(filename, orgname, strlen(orgname));
- strcat(filename, "/id");
-
- c = strchr(filename, ':');
- if (c)
- *c = '/';
-
- file = fopen(filename, "r");
- if (!file)
- return 0;
- n = fscanf(file, "%i", &id);
- fclose(file);
- if (n < 1) {
- pr_err("cannot store event ID\n");
- return -EINVAL;
- }
- return perf_header__push_event(id, orgname);
-}
-
int parse_events(const struct option *opt __used, const char *str, int unset __used)
{
struct perf_event_attr attr;
enum event_result ret;
- if (strchr(str, ':'))
- if (store_event_type(str) < 0)
- return -1;
-
for (;;) {
memset(&attr, 0, sizeof(attr));
ret = parse_event_symbols(&str, &attr);
@@ -824,7 +823,7 @@ int parse_events(const struct option *opt __used, const char *str, int unset __u
if (ret != EVT_HANDLED_ALL) {
struct perf_evsel *evsel;
- evsel = perf_evsel__new(attr.type, attr.config,
+ evsel = perf_evsel__new(&attr,
nr_counters);
if (evsel == NULL)
return -1;
@@ -1014,8 +1013,15 @@ void print_events(void)
int perf_evsel_list__create_default(void)
{
- struct perf_evsel *evsel = perf_evsel__new(PERF_TYPE_HARDWARE,
- PERF_COUNT_HW_CPU_CYCLES, 0);
+ struct perf_evsel *evsel;
+ struct perf_event_attr attr;
+
+ memset(&attr, 0, sizeof(attr));
+ attr.type = PERF_TYPE_HARDWARE;
+ attr.config = PERF_COUNT_HW_CPU_CYCLES;
+
+ evsel = perf_evsel__new(&attr, 0);
+
if (evsel == NULL)
return -ENOMEM;
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 6fb4694d05f..313dac2d94c 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1007,7 +1007,7 @@ more:
if (size == 0)
size = 8;
- if (head + event->header.size >= mmap_size) {
+ if (head + event->header.size > mmap_size) {
if (mmaps[map_idx]) {
munmap(mmaps[map_idx], mmap_size);
mmaps[map_idx] = NULL;