@@ -19,8 +19,9 @@
#include "tracefs-local.h"
enum {
- TC_STOP = 1 << 0, /* Stop reading */
- TC_NONBLOCK = 1 << 1, /* read is non blocking */
+ TC_STOP = 1 << 0, /* Stop reading */
+ TC_PERM_NONBLOCK = 1 << 1, /* read is always non blocking */
+ TC_NONBLOCK = 1 << 2, /* read is non blocking */
};
struct tracefs_cpu {
@@ -59,7 +60,7 @@ tracefs_cpu_alloc_fd(int fd, int subbuf_size, bool nonblock)
if (nonblock) {
mode |= O_NONBLOCK;
- tcpu->flags |= TC_NONBLOCK;
+ tcpu->flags |= TC_NONBLOCK | TC_PERM_NONBLOCK;
}
tcpu->splice_pipe[0] = -1;
@@ -69,7 +70,7 @@ tracefs_cpu_alloc_fd(int fd, int subbuf_size, bool nonblock)
tcpu->subbuf_size = subbuf_size;
- if (tcpu->flags & TC_NONBLOCK) {
+ if (tcpu->flags & TC_PERM_NONBLOCK) {
tcpu->ctrl_pipe[0] = -1;
tcpu->ctrl_pipe[1] = -1;
} else {
@@ -210,11 +211,27 @@ static void set_nonblock(struct tracefs_cpu *tcpu)
{
long flags;
+ if (tcpu->flags & TC_NONBLOCK)
+ return;
+
flags = fcntl(tcpu->fd, F_GETFL);
fcntl(tcpu->fd, F_SETFL, flags | O_NONBLOCK);
tcpu->flags |= TC_NONBLOCK;
}
+static void unset_nonblock(struct tracefs_cpu *tcpu)
+{
+ long flags;
+
+ if (!(tcpu->flags & TC_NONBLOCK))
+ return;
+
+ flags = fcntl(tcpu->fd, F_GETFL);
+ flags &= ~O_NONBLOCK;
+ fcntl(tcpu->fd, F_SETFL, flags);
+ tcpu->flags &= ~TC_NONBLOCK;
+}
+
/*
* If set to blocking mode, block until the watermark has been
* reached, or the control has said to stop. If the contol is
@@ -222,24 +239,24 @@ static void set_nonblock(struct tracefs_cpu *tcpu)
*/
static int wait_on_input(struct tracefs_cpu *tcpu, bool nonblock)
{
- struct timeval tv, *ptv = NULL;
fd_set rfds;
int ret;
- if (tcpu->flags & TC_NONBLOCK)
+ if (tcpu->flags & TC_PERM_NONBLOCK)
return 1;
if (nonblock) {
- tv.tv_sec = 0;
- tv.tv_usec = 0;
- ptv = &tv;
+ set_nonblock(tcpu);
+ return 1;
+ } else {
+ unset_nonblock(tcpu);
}
FD_ZERO(&rfds);
FD_SET(tcpu->fd, &rfds);
FD_SET(tcpu->ctrl_pipe[0], &rfds);
- ret = select(tcpu->nfds, &rfds, NULL, NULL, ptv);
+ ret = select(tcpu->nfds, &rfds, NULL, NULL, NULL);
/* Let the application decide what to do with signals and such */
if (ret < 0)
@@ -251,6 +268,8 @@ static int wait_on_input(struct tracefs_cpu *tcpu, bool nonblock)
/* Make nonblock as it is now stopped */
set_nonblock(tcpu);
+ /* Permanently set unblock */
+ tcpu->flags |= TC_PERM_NONBLOCK;
}
return FD_ISSET(tcpu->fd, &rfds);
@@ -275,8 +294,6 @@ static int wait_on_input(struct tracefs_cpu *tcpu, bool nonblock)
*/
int tracefs_cpu_read(struct tracefs_cpu *tcpu, void *buffer, bool nonblock)
{
- bool orig_nonblock = nonblock;
- long flags = 0;
int ret;
/*
@@ -290,8 +307,9 @@ int tracefs_cpu_read(struct tracefs_cpu *tcpu, void *buffer, bool nonblock)
ret = read(tcpu->fd, buffer, tcpu->subbuf_size);
- if (nonblock != orig_nonblock && !(tcpu->flags & TC_NONBLOCK))
- fcntl(tcpu->fd, F_SETFL, flags);
+ /* It's OK if there's no data to read */
+ if (ret < 0 && errno == EAGAIN)
+ ret = 0;
return ret;
}
@@ -360,7 +378,7 @@ int tracefs_cpu_buffered_read(struct tracefs_cpu *tcpu, void *buffer, bool nonbl
if (ret <= 0)
return ret;
- if (nonblock || tcpu->flags & TC_NONBLOCK)
+ if (tcpu->flags & TC_NONBLOCK)
mode |= SPLICE_F_NONBLOCK;
ret = init_splice(tcpu);
@@ -414,6 +432,8 @@ int tracefs_cpu_stop(struct tracefs_cpu *tcpu)
else
ret = 0;
+ set_nonblock(tcpu);
+
return ret;
}
@@ -436,8 +456,7 @@ int tracefs_cpu_flush(struct tracefs_cpu *tcpu, void *buffer)
int ret;
/* Make sure that reading is now non blocking */
- if (!(tcpu->flags & TC_NONBLOCK))
- set_nonblock(tcpu);
+ set_nonblock(tcpu);
if (tcpu->buffered < 0)
tcpu->buffered = 0;
@@ -505,7 +524,7 @@ int tracefs_cpu_write(struct tracefs_cpu *tcpu, int wfd, bool nonblock)
if (ret <= 0)
return ret;
- if (nonblock || tcpu->flags & TC_NONBLOCK)
+ if (tcpu->flags & TC_NONBLOCK)
mode |= SPLICE_F_NONBLOCK;
ret = init_splice(tcpu);
@@ -570,7 +589,7 @@ int tracefs_cpu_pipe(struct tracefs_cpu *tcpu, int wfd, bool nonblock)
if (ret <= 0)
return ret;
- if (nonblock || tcpu->flags & TC_NONBLOCK)
+ if (tcpu->flags & TC_NONBLOCK)
mode |= SPLICE_F_NONBLOCK;
ret = splice(tcpu->fd, NULL, wfd, NULL,
@@ -12,6 +12,8 @@
#include <dirent.h>
#include <ftw.h>
#include <libgen.h>
+#include <kbuffer.h>
+#include <pthread.h>
#include <CUnit/CUnit.h>
#include <CUnit/Basic.h>
@@ -98,10 +100,16 @@ static void save_affinity(void)
cpus = sysconf(_SC_NPROCESSORS_CONF);
cpuset_save = CPU_ALLOC(cpus);
cpuset = CPU_ALLOC(cpus);
+ cpu_size = CPU_ALLOC_SIZE(cpus);
CU_TEST(cpuset_save != NULL && cpuset != NULL);
CU_TEST(sched_getaffinity(0, cpu_size, cpuset_save) == 0);
}
+static void thread_affinity(void)
+{
+ sched_setaffinity(0, cpu_size, cpuset_save);
+}
+
static void reset_affinity(void)
{
sched_setaffinity(0, cpu_size, cpuset_save);
@@ -404,6 +412,317 @@ static void test_trace_sql(void)
test_instance_trace_sql(test_instance);
}
+struct test_cpu_data {
+ struct tracefs_instance *instance;
+ struct tracefs_cpu *tcpu;
+ struct kbuffer *kbuf;
+ struct tep_handle *tep;
+ unsigned long long missed_events;
+ void *buf;
+ int events_per_buf;
+ int bufsize;
+ int data_size;
+ int this_pid;
+ int fd;
+ bool done;
+};
+
+static void cleanup_trace_cpu(struct test_cpu_data *data)
+{
+ close(data->fd);
+ tep_free(data->tep);
+ tracefs_cpu_close(data->tcpu);
+ free(data->buf);
+ kbuffer_free(data->kbuf);
+}
+
+#define EVENT_SYSTEM "syscalls"
+#define EVENT_NAME "sys_enter_getppid"
+
+static int setup_trace_cpu(struct tracefs_instance *instance, struct test_cpu_data *data)
+{
+ struct tep_format_field **fields;
+ struct tep_event *event;
+ char tmpfile[] = "/tmp/utest-libtracefsXXXXXX";
+ int max = 0;
+ int ret;
+ int i;
+
+ /* Make sure tracing is on */
+ tracefs_trace_on(instance);
+
+ memset (data, 0, sizeof(*data));
+
+ data->instance = instance;
+
+ data->fd = mkstemp(tmpfile);
+ CU_TEST(data->fd >= 0);
+ unlink(tmpfile);
+ if (data->fd < 0)
+ return -1;
+
+ data->tep = tracefs_local_events(NULL);
+ CU_TEST(data->tep != NULL);
+ if (!data->tep)
+ goto fail;
+
+ data->tcpu = tracefs_cpu_open(instance, 0, true);
+ CU_TEST(data->tcpu != NULL);
+ if (!data->tcpu)
+ goto fail;
+
+ data->bufsize = tracefs_cpu_read_size(data->tcpu);
+
+ data->buf = calloc(1, data->bufsize);
+ CU_TEST(data->buf != NULL);
+ if (!data->buf)
+ goto fail;
+
+ data->kbuf = kbuffer_alloc(sizeof(long) == 8, !tep_is_bigendian());
+ CU_TEST(data->kbuf != NULL);
+ if (!data->kbuf)
+ goto fail;
+
+ data->data_size = data->bufsize - kbuffer_start_of_data(data->kbuf);
+
+ tracefs_instance_file_clear(instance, "trace");
+
+ event = tep_find_event_by_name(data->tep, EVENT_SYSTEM, EVENT_NAME);
+ CU_TEST(event != NULL);
+ if (!event)
+ goto fail;
+
+ fields = tep_event_fields(event);
+ CU_TEST(fields != NULL);
+ if (!fields)
+ goto fail;
+
+ for (i = 0; fields[i]; i++) {
+ int end = fields[i]->offset + fields[i]->size;
+ if (end > max)
+ max = end;
+ }
+ free(fields);
+
+ CU_TEST(max != 0);
+ if (!max)
+ goto fail;
+
+ data->events_per_buf = data->data_size / max;
+
+ data->this_pid = getpid();
+ ret = tracefs_event_enable(instance, EVENT_SYSTEM, EVENT_NAME);
+ CU_TEST(ret == 0);
+ if (ret)
+ goto fail;
+
+
+ save_affinity();
+ set_affinity(0);
+
+ return 0;
+ fail:
+ cleanup_trace_cpu(data);
+ return -1;
+}
+
+static void shutdown_trace_cpu(struct test_cpu_data *data)
+{
+ struct tracefs_instance *instance = data->instance;
+ int ret;
+
+ reset_affinity();
+
+ ret = tracefs_event_disable(instance, EVENT_SYSTEM, EVENT_NAME);
+ CU_TEST(ret == 0);
+
+ cleanup_trace_cpu(data);
+}
+
+static void call_getppid(int cnt)
+{
+ int i;
+
+ for (i = 0; i < cnt; i++)
+ getppid();
+}
+
+static void test_cpu_read(struct test_cpu_data *data, int expect)
+{
+ struct tracefs_cpu *tcpu = data->tcpu;
+ struct kbuffer *kbuf = data->kbuf;
+ struct tep_record record;
+ void *buf = data->buf;
+ unsigned long long ts;
+ bool first = true;
+ int pid;
+ int ret;
+ int cnt = 0;
+
+ call_getppid(expect);
+
+ for (;;) {
+ ret = tracefs_cpu_read(tcpu, buf, false);
+ CU_TEST(ret > 0 || !first);
+ if (ret <= 0)
+ break;
+ first = false;
+ ret = kbuffer_load_subbuffer(kbuf, buf);
+ CU_TEST(ret == 0);
+ for (;;) {
+ record.data = kbuffer_read_event(kbuf, &ts);
+ if (!record.data)
+ break;
+ record.ts = ts;
+ pid = tep_data_pid(data->tep, &record);
+ if (pid == data->this_pid)
+ cnt++;
+ kbuffer_next_event(kbuf, NULL);
+ }
+ }
+ CU_TEST(cnt == expect);
+}
+
+static void test_instance_trace_cpu_read(struct tracefs_instance *instance)
+{
+ struct test_cpu_data data;
+
+ if (setup_trace_cpu(instance, &data))
+ return;
+
+ test_cpu_read(&data, 1);
+ test_cpu_read(&data, data.events_per_buf / 2);
+ test_cpu_read(&data, data.events_per_buf);
+ test_cpu_read(&data, data.events_per_buf + 1);
+ test_cpu_read(&data, data.events_per_buf * 50);
+
+ shutdown_trace_cpu(&data);
+}
+
+static void test_trace_cpu_read(void)
+{
+ test_instance_trace_cpu_read(NULL);
+ test_instance_trace_cpu_read(test_instance);
+}
+
+static int read_trace_cpu_file(struct test_cpu_data *data)
+{
+ unsigned long long ts;
+ struct tep_record record;
+ struct kbuffer *kbuf = data->kbuf;
+ void *buf = data->buf;
+ bool first = true;
+ int bufsize = data->bufsize;
+ int fd = data->fd;
+ int missed;
+ int pid;
+ int ret;
+ int cnt = 0;
+
+ ret = lseek64(fd, 0, SEEK_SET);
+ CU_TEST(ret == 0);
+ if (ret)
+ return -1;
+
+ for (;;) {
+ ret = read(fd, buf, bufsize);
+ CU_TEST(ret > 0 || !first);
+ if (ret <= 0)
+ break;
+ first = false;
+
+ ret = kbuffer_load_subbuffer(kbuf, buf);
+ CU_TEST(ret == 0);
+ missed = kbuffer_missed_events(kbuf);
+ if (missed)
+ printf("missed events %d\n", missed);
+ for (;;) {
+ record.data = kbuffer_read_event(kbuf, &ts);
+ if (!record.data)
+ break;
+ record.ts = ts;
+ pid = tep_data_pid(data->tep, &record);
+ if (pid == data->this_pid)
+ cnt++;
+ kbuffer_next_event(kbuf, NULL);
+ }
+ }
+ return ret == 0 ? cnt : ret;
+}
+
+static void *trace_cpu_thread(void *arg)
+{
+ struct test_cpu_data *data = arg;
+ struct tracefs_cpu *tcpu = data->tcpu;
+ int fd = data->fd;
+ long ret = 0;
+
+ thread_affinity();
+
+ while (!data->done && ret >= 0) {
+ ret = tracefs_cpu_write(tcpu, fd, false);
+ if (ret < 0 && errno == EAGAIN)
+ ret = 0;
+ }
+ if (ret >= 0 || errno == EAGAIN) {
+ do {
+ ret = tracefs_cpu_flush_write(tcpu, fd);
+ } while (ret > 0);
+ }
+
+ return (void *)ret;
+}
+
+static void test_cpu_pipe(struct test_cpu_data *data, int expect)
+{
+ pthread_t thread;
+ void *retval;
+ long ret;
+ int cnt;
+
+ tracefs_instance_file_clear(data->instance, "trace");
+ ftruncate(data->fd, 0);
+
+ data->done = false;
+
+ pthread_create(&thread, NULL, trace_cpu_thread, data);
+ sleep(1);
+
+ call_getppid(expect);
+
+ data->done = true;
+ tracefs_cpu_stop(data->tcpu);
+ pthread_join(thread, &retval);
+ ret = (long)retval;
+ CU_TEST(ret >= 0);
+
+ cnt = read_trace_cpu_file(data);
+
+ CU_TEST(cnt == expect);
+}
+
+static void test_instance_trace_cpu_pipe(struct tracefs_instance *instance)
+{
+ struct test_cpu_data data;
+
+ if (setup_trace_cpu(instance, &data))
+ return;
+
+ test_cpu_pipe(&data, 1);
+ test_cpu_pipe(&data, data.events_per_buf / 2);
+ test_cpu_pipe(&data, data.events_per_buf);
+ test_cpu_pipe(&data, data.events_per_buf + 1);
+ test_cpu_pipe(&data, data.events_per_buf * 1000);
+
+ shutdown_trace_cpu(&data);
+}
+
+static void test_trace_cpu_pipe(void)
+{
+ test_instance_trace_cpu_pipe(NULL);
+ test_instance_trace_cpu_pipe(test_instance);
+}
+
static struct tracefs_dynevent **get_dynevents_check(enum tracefs_dynevent_type types, int count)
{
struct tracefs_dynevent **devents;
@@ -1794,6 +2113,10 @@ void test_tracefs_lib(void)
fprintf(stderr, "Suite \"%s\" cannot be ceated\n", TRACEFS_SUITE);
return;
}
+ CU_add_test(suite, "trace cpu read",
+ test_trace_cpu_read);
+ CU_add_test(suite, "trace cpu pipe",
+ test_trace_cpu_pipe);
CU_add_test(suite, "trace sql",
test_trace_sql);
CU_add_test(suite, "tracing file / directory APIs",