* [RFC PATCH v7 01/13] trace-cmd: Minor cleanup in tracecmd_start_recording()
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 02/13] trace-cmd: Minor cleanup in print_stat() Slavomir Kaslev
` (11 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
Initialize `struct timespec req` only once instead of on every loop iteration
since `sleep` is being constant throughout tracecmd_start_recording() execution.
No changes in behavior intended.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
lib/trace-cmd/trace-recorder.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/lib/trace-cmd/trace-recorder.c b/lib/trace-cmd/trace-recorder.c
index 0b8d98a..0bd0657 100644
--- a/lib/trace-cmd/trace-recorder.c
+++ b/lib/trace-cmd/trace-recorder.c
@@ -466,7 +466,10 @@ long tracecmd_flush_recording(struct tracecmd_recorder *recorder)
int tracecmd_start_recording(struct tracecmd_recorder *recorder, unsigned long sleep)
{
- struct timespec req;
+ struct timespec req = {
+ .tv_sec = sleep / 1000000,
+ .tv_nsec = (sleep % 1000000) * 1000,
+ };
long read = 1;
long ret;
@@ -474,11 +477,9 @@ int tracecmd_start_recording(struct tracecmd_recorder *recorder, unsigned long s
do {
/* Only sleep if we did not read anything last time */
- if (!read && sleep) {
- req.tv_sec = sleep / 1000000;
- req.tv_nsec = (sleep % 1000000) * 1000;
+ if (!read && sleep)
nanosleep(&req, NULL);
- }
+
read = 0;
do {
if (recorder->flags & TRACECMD_RECORD_NOSPLICE)
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 02/13] trace-cmd: Minor cleanup in print_stat()
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 01/13] trace-cmd: Minor cleanup in tracecmd_start_recording() Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 03/13] trace-cmd: Detect if vsockets are available Slavomir Kaslev
` (10 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
Do an early out in print_stat() when `quiet` is set instead of rechecking it on
each loop iteration.
No changes in behavior intended.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
tracecmd/trace-record.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index 8beefab..88b4a55 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -3106,13 +3106,14 @@ static void print_stat(struct buffer_instance *instance)
{
int cpu;
+ if (quiet)
+ return;
+
if (!is_top_instance(instance))
- if (!quiet)
- printf("\nBuffer: %s\n\n", instance->name);
+ printf("\nBuffer: %s\n\n", instance->name);
for (cpu = 0; cpu < instance->cpu_count; cpu++)
- if (!quiet)
- trace_seq_do_printf(&instance->s_print[cpu]);
+ trace_seq_do_printf(&instance->s_print[cpu]);
}
enum {
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 03/13] trace-cmd: Detect if vsockets are available
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 01/13] trace-cmd: Minor cleanup in tracecmd_start_recording() Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 02/13] trace-cmd: Minor cleanup in print_stat() Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 04/13] trace-cmd: Add tracecmd_create_recorder_virt function Slavomir Kaslev
` (9 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Detect and define VSOCK if vsockets are available on the system.
This macro is used to disable VM remote tracing features on older kernels.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
Makefile | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/Makefile b/Makefile
index b780718..99e4f39 100644
--- a/Makefile
+++ b/Makefile
@@ -204,6 +204,13 @@ CFLAGS ?= -g -Wall
CPPFLAGS ?=
LDFLAGS ?=
+VSOCK_DEFINED := $(shell if (echo "\#include <linux/vm_sockets.h>" | $(CC) -E - >/dev/null 2>&1) ; then echo 1; else echo 0 ; fi)
+
+export VSOCK_DEFINED
+ifeq ($(VSOCK_DEFINED), 1)
+CFLAGS += -DVSOCK
+endif
+
export CFLAGS
export INCLUDES
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 04/13] trace-cmd: Add tracecmd_create_recorder_virt function
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
` (2 preceding siblings ...)
2019-02-18 14:54 ` [RFC PATCH v7 03/13] trace-cmd: Detect if vsockets are available Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 05/13] trace-cmd: Add TRACE_REQ and TRACE_RESP messages Slavomir Kaslev
` (8 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
Add tracecmd_create_recorder_virt function that will be used for
tracing VM guests.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
include/trace-cmd/trace-cmd.h | 1 +
lib/trace-cmd/trace-recorder.c | 53 ++++++++++++++++++++++++----------
2 files changed, 39 insertions(+), 15 deletions(-)
diff --git a/include/trace-cmd/trace-cmd.h b/include/trace-cmd/trace-cmd.h
index ca4452b..5961355 100644
--- a/include/trace-cmd/trace-cmd.h
+++ b/include/trace-cmd/trace-cmd.h
@@ -277,6 +277,7 @@ enum {
void tracecmd_free_recorder(struct tracecmd_recorder *recorder);
struct tracecmd_recorder *tracecmd_create_recorder(const char *file, int cpu, unsigned flags);
struct tracecmd_recorder *tracecmd_create_recorder_fd(int fd, int cpu, unsigned flags);
+struct tracecmd_recorder *tracecmd_create_recorder_virt(const char *file, int cpu, unsigned flags, int trace_fd);
struct tracecmd_recorder *tracecmd_create_recorder_maxkb(const char *file, int cpu, unsigned flags, int maxkb);
struct tracecmd_recorder *tracecmd_create_buffer_recorder_fd(int fd, int cpu, unsigned flags, const char *buffer);
struct tracecmd_recorder *tracecmd_create_buffer_recorder(const char *file, int cpu, unsigned flags, const char *buffer);
diff --git a/lib/trace-cmd/trace-recorder.c b/lib/trace-cmd/trace-recorder.c
index 0bd0657..1b84bb5 100644
--- a/lib/trace-cmd/trace-recorder.c
+++ b/lib/trace-cmd/trace-recorder.c
@@ -154,16 +154,22 @@ tracecmd_create_buffer_recorder_fd2(int fd, int fd2, int cpu, unsigned flags,
recorder->fd1 = fd;
recorder->fd2 = fd2;
- if (flags & TRACECMD_RECORD_SNAPSHOT)
- ret = asprintf(&path, "%s/per_cpu/cpu%d/snapshot_raw", buffer, cpu);
- else
- ret = asprintf(&path, "%s/per_cpu/cpu%d/trace_pipe_raw", buffer, cpu);
- if (ret < 0)
- goto out_free;
+ if (buffer) {
+ if (flags & TRACECMD_RECORD_SNAPSHOT)
+ ret = asprintf(&path, "%s/per_cpu/cpu%d/snapshot_raw",
+ buffer, cpu);
+ else
+ ret = asprintf(&path, "%s/per_cpu/cpu%d/trace_pipe_raw",
+ buffer, cpu);
+ if (ret < 0)
+ goto out_free;
+
+ recorder->trace_fd = open(path, O_RDONLY);
+ free(path);
- recorder->trace_fd = open(path, O_RDONLY);
- if (recorder->trace_fd < 0)
- goto out_free;
+ if (recorder->trace_fd < 0)
+ goto out_free;
+ }
if ((recorder->flags & TRACECMD_RECORD_NOSPLICE) == 0) {
ret = pipe(recorder->brass);
@@ -183,13 +189,9 @@ tracecmd_create_buffer_recorder_fd2(int fd, int fd2, int cpu, unsigned flags,
recorder->pipe_size = pipe_size;
}
- free(path);
-
return recorder;
out_free:
- free(path);
-
tracecmd_free_recorder(recorder);
return NULL;
}
@@ -200,8 +202,9 @@ tracecmd_create_buffer_recorder_fd(int fd, int cpu, unsigned flags, const char *
return tracecmd_create_buffer_recorder_fd2(fd, -1, cpu, flags, buffer, 0);
}
-struct tracecmd_recorder *
-tracecmd_create_buffer_recorder(const char *file, int cpu, unsigned flags, const char *buffer)
+static struct tracecmd_recorder *
+__tracecmd_create_buffer_recorder(const char *file, int cpu, unsigned flags,
+ const char *buffer)
{
struct tracecmd_recorder *recorder;
int fd;
@@ -264,6 +267,26 @@ tracecmd_create_buffer_recorder_maxkb(const char *file, int cpu, unsigned flags,
goto out;
}
+struct tracecmd_recorder *
+tracecmd_create_buffer_recorder(const char *file, int cpu, unsigned flags,
+ const char *buffer)
+{
+ return __tracecmd_create_buffer_recorder(file, cpu, flags, buffer);
+}
+
+struct tracecmd_recorder *
+tracecmd_create_recorder_virt(const char *file, int cpu, unsigned flags,
+ int trace_fd)
+{
+ struct tracecmd_recorder *recorder;
+
+ recorder = __tracecmd_create_buffer_recorder(file, cpu, flags, NULL);
+ if (recorder)
+ recorder->trace_fd = trace_fd;
+
+ return recorder;
+}
+
struct tracecmd_recorder *tracecmd_create_recorder_fd(int fd, int cpu, unsigned flags)
{
const char *tracing;
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 05/13] trace-cmd: Add TRACE_REQ and TRACE_RESP messages
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
` (3 preceding siblings ...)
2019-02-18 14:54 ` [RFC PATCH v7 04/13] trace-cmd: Add tracecmd_create_recorder_virt function Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 06/13] trace-cmd: Add buffer instance flags for tracing in guest and agent context Slavomir Kaslev
` (7 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
Add TRACE_REQ and TRACE_RESP messages which are used for initiating guest VM
tracing.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
include/trace-cmd/trace-cmd.h | 12 ++
tracecmd/trace-msg.c | 211 +++++++++++++++++++++++++++++++++-
2 files changed, 222 insertions(+), 1 deletion(-)
diff --git a/include/trace-cmd/trace-cmd.h b/include/trace-cmd/trace-cmd.h
index 5961355..6a21e66 100644
--- a/include/trace-cmd/trace-cmd.h
+++ b/include/trace-cmd/trace-cmd.h
@@ -331,6 +331,18 @@ int tracecmd_msg_collect_data(struct tracecmd_msg_handle *msg_handle, int ofd);
bool tracecmd_msg_done(struct tracecmd_msg_handle *msg_handle);
void tracecmd_msg_set_done(struct tracecmd_msg_handle *msg_handle);
+int tracecmd_msg_send_trace_req(struct tracecmd_msg_handle *msg_handle,
+ int argc, char **argv);
+int tracecmd_msg_recv_trace_req(struct tracecmd_msg_handle *msg_handle,
+ int *argc, char ***argv);
+
+int tracecmd_msg_send_trace_resp(struct tracecmd_msg_handle *msg_handle,
+ int nr_cpus, int page_size,
+ unsigned int *ports);
+int tracecmd_msg_recv_trace_resp(struct tracecmd_msg_handle *msg_handle,
+ int *nr_cpus, int *page_size,
+ unsigned int **ports);
+
/* --- Plugin handling --- */
extern struct tep_plugin_option trace_ftrace_options[];
diff --git a/tracecmd/trace-msg.c b/tracecmd/trace-msg.c
index 51d0ac8..8ce1f98 100644
--- a/tracecmd/trace-msg.c
+++ b/tracecmd/trace-msg.c
@@ -16,6 +16,7 @@
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
+#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/types.h>
@@ -64,6 +65,17 @@ struct tracecmd_msg_rinit {
be32 cpus;
} __attribute__((packed));
+struct tracecmd_msg_trace_req {
+ be32 flags;
+ be32 argc;
+} __attribute__((packed));
+
+struct tracecmd_msg_trace_resp {
+ be32 flags;
+ be32 cpus;
+ be32 page_size;
+} __attribute__((packed));
+
struct tracecmd_msg_header {
be32 size;
be32 cmd;
@@ -76,7 +88,9 @@ struct tracecmd_msg_header {
C(RINIT, 2, sizeof(struct tracecmd_msg_rinit)), \
C(SEND_DATA, 3, 0), \
C(FIN_DATA, 4, 0), \
- C(NOT_SUPP, 5, 0),
+ C(NOT_SUPP, 5, 0), \
+ C(TRACE_REQ, 6, sizeof(struct tracecmd_msg_trace_req)), \
+ C(TRACE_RESP, 7, sizeof(struct tracecmd_msg_trace_resp)),
#undef C
#define C(a,b,c) MSG_##a = b
@@ -108,6 +122,8 @@ struct tracecmd_msg {
union {
struct tracecmd_msg_tinit tinit;
struct tracecmd_msg_rinit rinit;
+ struct tracecmd_msg_trace_req trace_req;
+ struct tracecmd_msg_trace_resp trace_resp;
};
union {
struct tracecmd_msg_opt *opt;
@@ -723,3 +739,196 @@ error:
msg_free(&msg);
return ret;
}
+
+static int make_trace_req(struct tracecmd_msg *msg, int argc, char **argv)
+{
+ size_t args_size = 0;
+ char *p;
+ int i;
+
+ for (i = 0; i < argc; i++)
+ args_size += strlen(argv[i]) + 1;
+
+ msg->hdr.size = htonl(ntohl(msg->hdr.size) + args_size);
+ msg->trace_req.argc = htonl(argc);
+ msg->buf = calloc(args_size, 1);
+ if (!msg->buf)
+ return -ENOMEM;
+
+ p = msg->buf;
+ for (i = 0; i < argc; i++)
+ p = stpcpy(p, argv[i]) + 1;
+
+ return 0;
+}
+
+int tracecmd_msg_send_trace_req(struct tracecmd_msg_handle *msg_handle,
+ int argc, char **argv)
+{
+ struct tracecmd_msg msg;
+ int ret;
+
+ tracecmd_msg_init(MSG_TRACE_REQ, &msg);
+ ret = make_trace_req(&msg, argc, argv);
+ if (ret < 0)
+ return ret;
+
+ return tracecmd_msg_send(msg_handle->fd, &msg);
+}
+
+ /*
+ * NOTE: On success, the returned `argv` should be freed with:
+ * free(argv[0]);
+ * free(argv);
+ */
+int tracecmd_msg_recv_trace_req(struct tracecmd_msg_handle *msg_handle,
+ int *argc, char ***argv)
+{
+ struct tracecmd_msg msg;
+ char *p, *buf_end, **args;
+ int i, ret, nr_args;
+ ssize_t buf_len;
+
+ ret = tracecmd_msg_recv(msg_handle->fd, &msg);
+ if (ret < 0)
+ return ret;
+
+ if (ntohl(msg.hdr.cmd) != MSG_TRACE_REQ) {
+ ret = -ENOTSUP;
+ goto out;
+ }
+
+ nr_args = ntohl(msg.trace_req.argc);
+ if (nr_args <= 0) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ buf_len = ntohl(msg.hdr.size) - MSG_HDR_LEN - ntohl(msg.hdr.cmd_size);
+ buf_end = (char *)msg.buf + buf_len;
+ if (buf_len <= 0 && ((char *)msg.buf)[buf_len-1] != '\0') {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ args = calloc(nr_args, sizeof(*args));
+ if (!args) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ p = msg.buf;
+ for (i = 0; i < nr_args; i++) {
+ if (p >= buf_end) {
+ ret = -EINVAL;
+ goto out_args;
+ }
+ args[i] = p;
+ p = strchr(p, '\0');
+ if (!p) {
+ ret = -EINVAL;
+ goto out_args;
+ }
+ p++;
+ }
+
+ *argc = nr_args;
+ *argv = args;
+
+ /*
+ * On success we're passing msg.buf to the caller through argv[0] so we
+ * reset it here before calling msg_free().
+ */
+ msg.buf = NULL;
+ msg_free(&msg);
+ return 0;
+
+out_args:
+ free(args);
+out:
+ error_operation(&msg);
+ if (ret == -EOPNOTSUPP)
+ handle_unexpected_msg(msg_handle, &msg);
+ msg_free(&msg);
+ return ret;
+}
+
+static int make_trace_resp(struct tracecmd_msg *msg,
+ int page_size, int nr_cpus, unsigned int *ports)
+{
+ int ports_size = nr_cpus * sizeof(*msg->port_array);
+ int i;
+
+ msg->hdr.size = htonl(ntohl(msg->hdr.size) + ports_size);
+ msg->trace_resp.cpus = htonl(nr_cpus);
+ msg->trace_resp.page_size = htonl(page_size);
+
+ msg->port_array = malloc(ports_size);
+ if (!msg->port_array)
+ return -ENOMEM;
+
+ for (i = 0; i < nr_cpus; i++)
+ msg->port_array[i] = htonl(ports[i]);
+
+ return 0;
+}
+
+int tracecmd_msg_send_trace_resp(struct tracecmd_msg_handle *msg_handle,
+ int nr_cpus, int page_size,
+ unsigned int *ports)
+{
+ struct tracecmd_msg msg;
+ int ret;
+
+ tracecmd_msg_init(MSG_TRACE_RESP, &msg);
+ ret = make_trace_resp(&msg, page_size, nr_cpus, ports);
+ if (ret < 0)
+ return ret;
+
+ return tracecmd_msg_send(msg_handle->fd, &msg);
+}
+
+int tracecmd_msg_recv_trace_resp(struct tracecmd_msg_handle *msg_handle,
+ int *nr_cpus, int *page_size,
+ unsigned int **ports)
+{
+ struct tracecmd_msg msg;
+ ssize_t buf_len;
+ int i, ret;
+
+ ret = tracecmd_msg_recv(msg_handle->fd, &msg);
+ if (ret < 0)
+ return ret;
+
+ if (ntohl(msg.hdr.cmd) != MSG_TRACE_RESP) {
+ ret = -ENOTSUP;
+ goto out;
+ }
+
+ buf_len = ntohl(msg.hdr.size) - MSG_HDR_LEN - ntohl(msg.hdr.cmd_size);
+ if (buf_len <= 0 ||
+ buf_len != sizeof(*msg.port_array) * ntohl(msg.trace_resp.cpus)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ *nr_cpus = ntohl(msg.trace_resp.cpus);
+ *page_size = ntohl(msg.trace_resp.page_size);
+ *ports = calloc(*nr_cpus, sizeof(**ports));
+ if (!*ports) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ for (i = 0; i < *nr_cpus; i++)
+ (*ports)[i] = ntohl(msg.port_array[i]);
+
+ msg_free(&msg);
+ return 0;
+
+out:
+ error_operation(&msg);
+ if (ret == -EOPNOTSUPP)
+ handle_unexpected_msg(msg_handle, &msg);
+ msg_free(&msg);
+ return ret;
+}
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 06/13] trace-cmd: Add buffer instance flags for tracing in guest and agent context
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
` (4 preceding siblings ...)
2019-02-18 14:54 ` [RFC PATCH v7 05/13] trace-cmd: Add TRACE_REQ and TRACE_RESP messages Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 07/13] trace-cmd: Add VM kernel tracing over vsockets transport Slavomir Kaslev
` (6 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
Add BUFFER_FL_GUEST and BUFFER_FL_AGENT flags to differentiate when
trace-record.c is being called to trace guest or the VM tracing agent.
Also disable functions talking to the local tracefs when called in recording
guest instances context.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
tracecmd/include/trace-local.h | 5 ++++
tracecmd/trace-record.c | 55 ++++++++++++++++++++++++++++++++--
2 files changed, 58 insertions(+), 2 deletions(-)
diff --git a/tracecmd/include/trace-local.h b/tracecmd/include/trace-local.h
index a1a06e9..f43c9d8 100644
--- a/tracecmd/include/trace-local.h
+++ b/tracecmd/include/trace-local.h
@@ -149,6 +149,8 @@ char *strstrip(char *str);
enum buffer_instance_flags {
BUFFER_FL_KEEP = 1 << 0,
BUFFER_FL_PROFILE = 1 << 1,
+ BUFFER_FL_GUEST = 1 << 2,
+ BUFFER_FL_AGENT = 1 << 3,
};
struct func_list {
@@ -198,6 +200,9 @@ extern struct buffer_instance *first_instance;
#define for_all_instances(i) for (i = first_instance; i; \
i = i == &top_instance ? buffer_instances : (i)->next)
+#define is_agent(instance) ((instance)->flags & BUFFER_FL_AGENT)
+#define is_guest(instance) ((instance)->flags & BUFFER_FL_GUEST)
+
struct buffer_instance *create_instance(const char *name);
void add_instance(struct buffer_instance *instance, int cpu_count);
char *get_instance_file(struct buffer_instance *instance, const char *file);
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index 88b4a55..69c8d67 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -781,6 +781,9 @@ static void __clear_trace(struct buffer_instance *instance)
FILE *fp;
char *path;
+ if (is_guest(instance))
+ return;
+
/* reset the trace */
path = get_instance_file(instance, "trace");
fp = fopen(path, "w");
@@ -1264,6 +1267,9 @@ set_plugin_instance(struct buffer_instance *instance, const char *name)
char *path;
char zero = '0';
+ if (is_guest(instance))
+ return;
+
path = get_instance_file(instance, "current_tracer");
fp = fopen(path, "w");
if (!fp) {
@@ -1360,6 +1366,9 @@ static void disable_func_stack_trace_instance(struct buffer_instance *instance)
int size;
int ret;
+ if (is_guest(instance))
+ return;
+
path = get_instance_file(instance, "current_tracer");
ret = stat(path, &st);
tracecmd_put_tracing_file(path);
@@ -1553,6 +1562,9 @@ reset_events_instance(struct buffer_instance *instance)
int i;
int ret;
+ if (is_guest(instance))
+ return;
+
if (use_old_event_method()) {
/* old way only had top instance */
if (!is_top_instance(instance))
@@ -1904,6 +1916,9 @@ static void write_tracing_on(struct buffer_instance *instance, int on)
int ret;
int fd;
+ if (is_guest(instance))
+ return;
+
fd = open_tracing_on(instance);
if (fd < 0)
return;
@@ -1923,6 +1938,9 @@ static int read_tracing_on(struct buffer_instance *instance)
char buf[10];
int ret;
+ if (is_guest(instance))
+ return -1;
+
fd = open_tracing_on(instance);
if (fd < 0)
return fd;
@@ -2156,6 +2174,9 @@ static void set_mask(struct buffer_instance *instance)
int fd;
int ret;
+ if (is_guest(instance))
+ return;
+
if (!instance->cpumask)
return;
@@ -2186,6 +2207,9 @@ static void enable_events(struct buffer_instance *instance)
{
struct event_list *event;
+ if (is_guest(instance))
+ return;
+
for (event = instance->events; event; event = event->next) {
if (!event->neg)
update_event(event, event->filter, 0, '1');
@@ -2209,6 +2233,9 @@ static void set_clock(struct buffer_instance *instance)
char *content;
char *str;
+ if (is_guest(instance))
+ return;
+
if (!instance->clock)
return;
@@ -2238,6 +2265,9 @@ static void set_max_graph_depth(struct buffer_instance *instance, char *max_grap
char *path;
int ret;
+ if (is_guest(instance))
+ return;
+
path = get_instance_file(instance, "max_graph_depth");
reset_save_file(path, RESET_DEFAULT_PRIO);
tracecmd_put_tracing_file(path);
@@ -2463,6 +2493,9 @@ static void expand_event_instance(struct buffer_instance *instance)
struct event_list *compressed_list = instance->events;
struct event_list *event;
+ if (is_guest(instance))
+ return;
+
reset_event_list(instance);
while (compressed_list) {
@@ -3337,6 +3370,9 @@ static void set_funcs(struct buffer_instance *instance)
int set_notrace = 0;
int ret;
+ if (is_guest(instance))
+ return;
+
ret = write_func_file(instance, "set_ftrace_filter", &instance->filter_funcs);
if (ret < 0)
die("set_ftrace_filter does not exist. Can not filter functions");
@@ -3633,6 +3669,9 @@ static void set_buffer_size_instance(struct buffer_instance *instance)
int ret;
int fd;
+ if (is_guest(instance))
+ return;
+
if (!buffer_size)
return;
@@ -3830,6 +3869,9 @@ static void make_instances(void)
int ret;
for_each_instance(instance) {
+ if (is_guest(instance))
+ continue;
+
path = get_instance_dir(instance);
ret = stat(path, &st);
if (ret < 0) {
@@ -3851,7 +3893,7 @@ void tracecmd_remove_instances(void)
for_each_instance(instance) {
/* Only delete what we created */
- if (instance->flags & BUFFER_FL_KEEP)
+ if (is_guest(instance) || (instance->flags & BUFFER_FL_KEEP))
continue;
if (instance->tracing_on_fd > 0) {
close(instance->tracing_on_fd);
@@ -3933,7 +3975,7 @@ static void check_function_plugin(void)
static int __check_doing_something(struct buffer_instance *instance)
{
- return (instance->flags & BUFFER_FL_PROFILE) ||
+ return is_guest(instance) || (instance->flags & BUFFER_FL_PROFILE) ||
instance->plugin || instance->events;
}
@@ -3955,6 +3997,9 @@ update_plugin_instance(struct buffer_instance *instance,
{
const char *plugin = instance->plugin;
+ if (is_guest(instance))
+ return;
+
if (!plugin)
return;
@@ -4054,6 +4099,9 @@ static void record_stats(void)
int cpu;
for_all_instances(instance) {
+ if (is_guest(instance))
+ continue;
+
s_save = instance->s_save;
s_print = instance->s_print;
for (cpu = 0; cpu < instance->cpu_count; cpu++) {
@@ -4080,6 +4128,9 @@ static void destroy_stats(void)
int cpu;
for_all_instances(instance) {
+ if (is_guest(instance))
+ continue;
+
for (cpu = 0; cpu < instance->cpu_count; cpu++) {
trace_seq_destroy(&instance->s_save[cpu]);
trace_seq_destroy(&instance->s_print[cpu]);
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 07/13] trace-cmd: Add VM kernel tracing over vsockets transport
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
` (5 preceding siblings ...)
2019-02-18 14:54 ` [RFC PATCH v7 06/13] trace-cmd: Add buffer instance flags for tracing in guest and agent context Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 08/13] trace-cmd: Use splice(2) for vsockets if available Slavomir Kaslev
` (5 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
This patch adds VM tracing over vsockets. The new `trace-cmd agent` command
needs run on each guest we want to trace:
you@guest2 # trace-cmd agent
Then `trace-cmd record` on the host can collect data from both the host and
several guests simultaneously:
you@host $ trace-cmd record -A guest1 -e irq -e sched \
-A guest2 -p function -e all
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
tracecmd/Makefile | 6 +-
tracecmd/include/trace-local.h | 16 +
tracecmd/trace-agent.c | 225 +++++++++++++
tracecmd/trace-cmd.c | 3 +
tracecmd/trace-record.c | 596 ++++++++++++++++++++++++++++++---
tracecmd/trace-usage.c | 13 +-
6 files changed, 814 insertions(+), 45 deletions(-)
create mode 100644 tracecmd/trace-agent.c
diff --git a/tracecmd/Makefile b/tracecmd/Makefile
index 3a11024..865b1c6 100644
--- a/tracecmd/Makefile
+++ b/tracecmd/Makefile
@@ -33,13 +33,17 @@ TRACE_CMD_OBJS += trace-output.o
TRACE_CMD_OBJS += trace-usage.o
TRACE_CMD_OBJS += trace-msg.o
+ifeq ($(VSOCK_DEFINED), 1)
+TRACE_CMD_OBJS += trace-agent.o
+endif
+
ALL_OBJS := $(TRACE_CMD_OBJS:%.o=$(bdir)/%.o)
all_objs := $(sort $(ALL_OBJS))
all_deps := $(all_objs:$(bdir)/%.o=$(bdir)/.%.d)
CONFIG_INCLUDES =
-CONFIG_LIBS =
+CONFIG_LIBS = -lrt
CONFIG_FLAGS =
all: $(TARGETS)
diff --git a/tracecmd/include/trace-local.h b/tracecmd/include/trace-local.h
index f43c9d8..95cf512 100644
--- a/tracecmd/include/trace-local.h
+++ b/tracecmd/include/trace-local.h
@@ -12,6 +12,8 @@
#include "trace-cmd.h"
#include "event-utils.h"
+#define TRACE_AGENT_DEFAULT_PORT 823
+
extern int debug;
extern int quiet;
@@ -64,6 +66,8 @@ void trace_split(int argc, char **argv);
void trace_listen(int argc, char **argv);
+void trace_agent(int argc, char **argv);
+
void trace_restore(int argc, char **argv);
void trace_clear(int argc, char **argv);
@@ -88,6 +92,10 @@ void trace_list(int argc, char **argv);
void trace_usage(int argc, char **argv);
+int trace_record_agent(struct tracecmd_msg_handle *msg_handle,
+ int cpus, int *fds,
+ int argc, char **argv);
+
struct hook_list;
void trace_init_profile(struct tracecmd_input *handle, struct hook_list *hooks,
@@ -176,6 +184,7 @@ struct buffer_instance {
struct func_list *notrace_funcs;
const char *clock;
+ unsigned int *client_ports;
struct trace_seq *s_save;
struct trace_seq *s_print;
@@ -190,6 +199,13 @@ struct buffer_instance {
int tracing_on_fd;
int buffer_size;
int cpu_count;
+
+ int argc;
+ char **argv;
+
+ int cid;
+ int port;
+ int *fds;
};
extern struct buffer_instance top_instance;
diff --git a/tracecmd/trace-agent.c b/tracecmd/trace-agent.c
new file mode 100644
index 0000000..0c0873b
--- /dev/null
+++ b/tracecmd/trace-agent.c
@@ -0,0 +1,225 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 VMware Inc, Slavomir Kaslev <kaslevs@vmware.com>
+ *
+ * based on prior implementation by Yoshihiro Yunomae
+ * Copyright (C) 2013 Hitachi, Ltd.
+ * Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <linux/vm_sockets.h>
+
+#include "trace-local.h"
+#include "trace-msg.h"
+
+static int make_vsock(unsigned int port)
+{
+ struct sockaddr_vm addr = {
+ .svm_family = AF_VSOCK,
+ .svm_cid = VMADDR_CID_ANY,
+ .svm_port = port,
+ };
+ int sd;
+
+ sd = socket(AF_VSOCK, SOCK_STREAM, 0);
+ if (sd < 0)
+ return -errno;
+
+ setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &(int){1}, sizeof(int));
+
+ if (bind(sd, (struct sockaddr *)&addr, sizeof(addr)))
+ return -errno;
+
+ if (listen(sd, SOMAXCONN))
+ return -errno;
+
+ return sd;
+}
+
+static int get_vsock_port(int sd, unsigned int *port)
+{
+ struct sockaddr_vm addr;
+ socklen_t addr_len = sizeof(addr);
+
+ if (getsockname(sd, (struct sockaddr *)&addr, &addr_len))
+ return -errno;
+
+ if (addr.svm_family != AF_VSOCK)
+ return -errno;
+
+ if (port)
+ *port = addr.svm_port;
+
+ return 0;
+}
+
+static void make_vsocks(int nr, int *fds, unsigned int *ports)
+{
+ unsigned int port;
+ int i, fd, ret;
+
+ for (i = 0; i < nr; i++) {
+ fd = make_vsock(VMADDR_PORT_ANY);
+ if (fd < 0)
+ die("Failed to open vsocket");
+
+ ret = get_vsock_port(fd, &port);
+ if (ret < 0)
+ die("Failed to get vsocket address");
+
+ fds[i] = fd;
+ ports[i] = port;
+ }
+}
+
+static void agent_handle(int sd, int nr_cpus, int page_size)
+{
+ struct tracecmd_msg_handle *msg_handle;
+ unsigned int *ports;
+ char **argv = NULL;
+ int argc = 0;
+ int *fds;
+ int ret;
+
+ fds = calloc(nr_cpus, sizeof(*fds));
+ ports = calloc(nr_cpus, sizeof(*ports));
+ if (!fds || !ports)
+ die("Failed to allocate memory");
+
+ msg_handle = tracecmd_msg_handle_alloc(sd, 0);
+ if (!msg_handle)
+ die("Failed to allocate message handle");
+
+ ret = tracecmd_msg_recv_trace_req(msg_handle, &argc, &argv);
+ if (ret < 0)
+ die("Failed to receive trace request");
+
+ make_vsocks(nr_cpus, fds, ports);
+
+ ret = tracecmd_msg_send_trace_resp(msg_handle, nr_cpus, page_size, ports);
+ if (ret < 0)
+ die("Failed to send trace response");
+
+ trace_record_agent(msg_handle, nr_cpus, fds, argc, argv);
+
+ free(argv[0]);
+ free(argv);
+ free(ports);
+ free(fds);
+ tracecmd_msg_handle_close(msg_handle);
+ exit(0);
+}
+
+static volatile pid_t handler_pid;
+
+static void handle_sigchld(int sig)
+{
+ int wstatus;
+ pid_t pid;
+
+ for (;;) {
+ pid = waitpid(-1, &wstatus, WNOHANG);
+ if (pid <= 0)
+ break;
+
+ if (pid == handler_pid)
+ handler_pid = 0;
+ }
+}
+
+static void agent_serve(unsigned int port)
+{
+ int sd, cd, nr_cpus;
+ pid_t pid;
+
+ signal(SIGCHLD, handle_sigchld);
+
+ nr_cpus = count_cpus();
+ page_size = getpagesize();
+
+ sd = make_vsock(port);
+ if (sd < 0)
+ die("Failed to open vsocket");
+
+ for (;;) {
+ cd = accept(sd, NULL, NULL);
+ if (cd < 0) {
+ if (errno == EINTR)
+ continue;
+ die("accept");
+ }
+
+ if (handler_pid)
+ goto busy;
+
+ pid = fork();
+ if (pid == 0) {
+ close(sd);
+ signal(SIGCHLD, SIG_DFL);
+ agent_handle(cd, nr_cpus, page_size);
+ }
+ if (pid > 0)
+ handler_pid = pid;
+
+busy:
+ close(cd);
+ }
+}
+
+void trace_agent(int argc, char **argv)
+{
+ bool do_daemon = false;
+ unsigned int port = TRACE_AGENT_DEFAULT_PORT;
+
+ if (argc < 2)
+ usage(argv);
+
+ if (strcmp(argv[1], "agent") != 0)
+ usage(argv);
+
+ for (;;) {
+ int c, option_index = 0;
+ static struct option long_options[] = {
+ {"port", required_argument, NULL, 'p'},
+ {"help", no_argument, NULL, '?'},
+ {NULL, 0, NULL, 0}
+ };
+
+ c = getopt_long(argc-1, argv+1, "+hp:D",
+ long_options, &option_index);
+ if (c == -1)
+ break;
+ switch (c) {
+ case 'h':
+ usage(argv);
+ break;
+ case 'p':
+ port = atoi(optarg);
+ break;
+ case 'D':
+ do_daemon = true;
+ break;
+ default:
+ usage(argv);
+ }
+ }
+
+ if (optind < argc-1)
+ usage(argv);
+
+ if (do_daemon && daemon(1, 0))
+ die("daemon");
+
+ agent_serve(port);
+}
diff --git a/tracecmd/trace-cmd.c b/tracecmd/trace-cmd.c
index 797b303..3ae5e2e 100644
--- a/tracecmd/trace-cmd.c
+++ b/tracecmd/trace-cmd.c
@@ -83,6 +83,9 @@ struct command commands[] = {
{"hist", trace_hist},
{"mem", trace_mem},
{"listen", trace_listen},
+#ifdef VSOCK
+ {"agent", trace_agent},
+#endif
{"split", trace_split},
{"restore", trace_restore},
{"stack", trace_stack},
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index 69c8d67..b401fd9 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -33,6 +33,9 @@
#include <errno.h>
#include <limits.h>
#include <libgen.h>
+#ifdef VSOCK
+#include <linux/vm_sockets.h>
+#endif
#include "trace-local.h"
#include "trace-msg.h"
@@ -74,8 +77,6 @@ static int buffers;
static int clear_function_filters;
static char *host;
-static unsigned int *client_ports;
-static int sfd;
/* Max size to let a per cpu file get */
static int max_kb;
@@ -518,6 +519,22 @@ static char *get_temp_file(struct buffer_instance *instance, int cpu)
return file;
}
+static char *get_guest_file(const char *file, const char *guest)
+{
+ const char *p;
+ char *out = NULL;
+ int base_len;
+
+ p = strrchr(file, '.');
+ if (p && p != file)
+ base_len = p - file;
+ else
+ base_len = strlen(file);
+
+ asprintf(&out, "%.*s-%s%s", base_len, file, guest, file + base_len);
+ return out;
+}
+
static void put_temp_file(char *file)
{
free(file);
@@ -623,11 +640,22 @@ static void delete_thread_data(void)
}
}
+static void tell_guests_to_stop(void)
+{
+ struct buffer_instance *instance;
+
+ for_all_instances(instance) {
+ if (is_guest(instance)) {
+ tracecmd_msg_send_close_msg(instance->msg_handle);
+ tracecmd_msg_handle_close(instance->msg_handle);
+ }
+ }
+}
+
static void stop_threads(enum trace_type type)
{
struct timeval tv = { 0, 0 };
- int ret;
- int i;
+ int i, ret;
if (!recorder_threads)
return;
@@ -645,6 +673,11 @@ static void stop_threads(enum trace_type type)
ret = trace_stream_read(pids, recorder_threads, &tv);
} while (ret > 0);
}
+}
+
+static void wait_threads()
+{
+ int i;
for (i = 0; i < recorder_threads; i++) {
if (pids[i].pid > 0) {
@@ -2571,14 +2604,14 @@ static void flush(int sig)
tracecmd_stop_recording(recorder);
}
-static void connect_port(int cpu)
+static int connect_port(const char *host, unsigned int port)
{
struct addrinfo hints;
struct addrinfo *results, *rp;
- int s;
+ int s, sfd;
char buf[BUFSIZ];
- snprintf(buf, BUFSIZ, "%u", client_ports[cpu]);
+ snprintf(buf, BUFSIZ, "%u", port);
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_UNSPEC;
@@ -2605,7 +2638,190 @@ static void connect_port(int cpu)
freeaddrinfo(results);
- client_ports[cpu] = sfd;
+ return sfd;
+}
+
+#ifdef VSOCK
+static int open_vsock(unsigned int cid, unsigned int port)
+{
+ struct sockaddr_vm addr = {
+ .svm_family = AF_VSOCK,
+ .svm_cid = cid,
+ .svm_port = port,
+ };
+ int sd;
+
+ sd = socket(AF_VSOCK, SOCK_STREAM, 0);
+ if (sd < 0)
+ return -1;
+
+ if (connect(sd, (struct sockaddr *)&addr, sizeof(addr)))
+ return -1;
+
+ return sd;
+}
+#else
+static inline int open_vsock(unsigned int cid, unsigned int port)
+{
+ die("vsock is not supported");
+ return -1;
+}
+#endif
+
+static int do_accept(int sd)
+{
+ int cd;
+
+ for (;;) {
+ cd = accept(sd, NULL, NULL);
+ if (cd < 0) {
+ if (errno == EINTR)
+ continue;
+ die("accept");
+ }
+
+ return cd;
+ }
+
+ return -1;
+}
+
+static bool is_digits(const char *s)
+{
+ const char *p;
+
+ for (p = s; *p; p++)
+ if (!isdigit(*p))
+ return false;
+
+ return true;
+}
+
+struct guest {
+ char *name;
+ int cid;
+ int pid;
+};
+
+static struct guest *guests;
+static size_t guests_len;
+
+static char *get_qemu_guest_name(char *arg)
+{
+ char *tok, *end = arg;
+
+ while ((tok = strsep(&end, ","))) {
+ if (strncmp(tok, "guest=", 6) == 0)
+ return tok + 6;
+ }
+
+ return arg;
+}
+
+static void read_qemu_guests(void)
+{
+ static bool initialized;
+ struct dirent *entry;
+ char path[PATH_MAX];
+ DIR *dir;
+
+ if (initialized)
+ return;
+
+ initialized = true;
+ dir = opendir("/proc");
+ if (!dir)
+ die("opendir");
+
+ for (entry = readdir(dir); entry; entry = readdir(dir)) {
+ bool is_qemu = false, last_was_name = false;
+ struct guest guest = {};
+ char *p, *arg = NULL;
+ size_t arg_size = 0;
+ FILE *f;
+
+ if (!(entry->d_type == DT_DIR && is_digits(entry->d_name)))
+ continue;
+
+ guest.pid = atoi(entry->d_name);
+ snprintf(path, sizeof(path), "/proc/%s/cmdline", entry->d_name);
+ f = fopen(path, "r");
+ if (!f)
+ continue;
+
+ while (getdelim(&arg, &arg_size, 0, f) != -1) {
+ if (!is_qemu && strstr(arg, "qemu-system-")) {
+ is_qemu = true;
+ continue;
+ }
+
+ if (!is_qemu)
+ continue;
+
+ if (strcmp(arg, "-name") == 0) {
+ last_was_name = true;
+ continue;
+ }
+
+ if (last_was_name) {
+ guest.name = strdup(get_qemu_guest_name(arg));
+ last_was_name = false;
+ continue;
+ }
+
+ p = strstr(arg, "guest-cid=");
+ if (p) {
+ guest.cid = atoi(p + 10);
+ continue;
+ }
+ }
+
+ if (!is_qemu)
+ goto next;
+
+ guests = realloc(guests, (guests_len + 1) * sizeof(*guests));
+ if (!guests)
+ die("Can not allocate guest buffer");
+ guests[guests_len++] = guest;
+
+next:
+ free(arg);
+ fclose(f);
+ }
+
+ closedir(dir);
+}
+
+static char *parse_guest_name(char *guest, int *cid, int *port)
+{
+ size_t i;
+ char *p;
+
+ *port = -1;
+ p = strrchr(guest, ':');
+ if (p) {
+ *p = '\0';
+ *port = atoi(p + 1);
+ }
+
+ *cid = -1;
+ p = strrchr(guest, '@');
+ if (p) {
+ *p = '\0';
+ *cid = atoi(p + 1);
+ } else if (is_digits(guest))
+ *cid = atoi(guest);
+
+ read_qemu_guests();
+ for (i = 0; i < guests_len; i++) {
+ if ((*cid > 0 && *cid == guests[i].cid) ||
+ strcmp(guest, guests[i].name) == 0) {
+ *cid = guests[i].cid;
+ return guests[i].name;
+ }
+ }
+
+ return guest;
}
static void set_prio(int prio)
@@ -2652,6 +2868,17 @@ create_recorder_instance(struct buffer_instance *instance, const char *file, int
struct tracecmd_recorder *record;
char *path;
+ if (is_guest(instance)) {
+ int fd;
+
+ fd = open_vsock(instance->cid, instance->client_ports[cpu]);
+ if (fd < 0)
+ die("Failed to connect to agent");
+
+ return tracecmd_create_recorder_virt(
+ file, cpu, recorder_flags | TRACECMD_RECORD_NOSPLICE, fd);
+ }
+
if (brass)
return create_recorder_instance_pipe(instance, cpu, brass);
@@ -2676,7 +2903,7 @@ static int create_recorder(struct buffer_instance *instance, int cpu,
{
long ret;
char *file;
- int pid;
+ pid_t pid;
if (type != TRACE_TYPE_EXTRACT) {
signal(SIGUSR1, flush);
@@ -2695,19 +2922,23 @@ static int create_recorder(struct buffer_instance *instance, int cpu,
instance->cpu_count = 0;
}
- if (client_ports) {
- char *path;
+ if ((instance->client_ports && !is_guest(instance)) || is_agent(instance)) {
+ unsigned int flags = recorder_flags;
+ char *path = NULL;
+ int fd;
- connect_port(cpu);
- if (instance->name)
+ if (is_agent(instance))
+ fd = do_accept(instance->fds[cpu]);
+ else
+ fd = connect_port(host, instance->client_ports[cpu]);
+ if (fd < 0)
+ die("Failed connecting to client");
+ if (instance->name && !is_agent(instance))
path = get_instance_dir(instance);
else
path = tracecmd_find_tracing_dir();
- recorder = tracecmd_create_buffer_recorder_fd(client_ports[cpu],
- cpu, recorder_flags,
- path);
- if (instance->name)
- tracecmd_put_tracing_file(path);
+ recorder = tracecmd_create_buffer_recorder_fd(fd, cpu, flags, path);
+ tracecmd_put_tracing_file(path);
} else {
file = get_temp_file(instance, cpu);
recorder = create_recorder_instance(instance, file, cpu, brass);
@@ -2745,7 +2976,8 @@ static void check_first_msg_from_server(struct tracecmd_msg_handle *msg_handle)
die("server not tracecmd server");
}
-static void communicate_with_listener_v1(struct tracecmd_msg_handle *msg_handle)
+static void communicate_with_listener_v1(struct tracecmd_msg_handle *msg_handle,
+ unsigned int **client_ports)
{
char buf[BUFSIZ];
ssize_t n;
@@ -2788,8 +3020,8 @@ static void communicate_with_listener_v1(struct tracecmd_msg_handle *msg_handle)
/* No options */
write(msg_handle->fd, "0", 2);
- client_ports = malloc(local_cpu_count * sizeof(*client_ports));
- if (!client_ports)
+ *client_ports = malloc(local_cpu_count * sizeof(*client_ports));
+ if (!*client_ports)
die("Failed to allocate client ports for %d cpus", local_cpu_count);
/*
@@ -2807,13 +3039,14 @@ static void communicate_with_listener_v1(struct tracecmd_msg_handle *msg_handle)
if (i == BUFSIZ)
die("read bad port number");
buf[i] = 0;
- client_ports[cpu] = atoi(buf);
+ (*client_ports)[cpu] = atoi(buf);
}
}
-static void communicate_with_listener_v3(struct tracecmd_msg_handle *msg_handle)
+static void communicate_with_listener_v3(struct tracecmd_msg_handle *msg_handle,
+ unsigned int **client_ports)
{
- if (tracecmd_msg_send_init_data(msg_handle, &client_ports) < 0)
+ if (tracecmd_msg_send_init_data(msg_handle, client_ports) < 0)
die("Cannot communicate with server");
}
@@ -2864,7 +3097,7 @@ static void check_protocol_version(struct tracecmd_msg_handle *msg_handle)
}
}
-static struct tracecmd_msg_handle *setup_network(void)
+static struct tracecmd_msg_handle *setup_network(struct buffer_instance *instance)
{
struct tracecmd_msg_handle *msg_handle = NULL;
struct addrinfo hints;
@@ -2934,11 +3167,11 @@ again:
close(sfd);
goto again;
}
- communicate_with_listener_v3(msg_handle);
+ communicate_with_listener_v3(msg_handle, &instance->client_ports);
}
if (msg_handle->version == V1_PROTOCOL)
- communicate_with_listener_v1(msg_handle);
+ communicate_with_listener_v1(msg_handle, &instance->client_ports);
return msg_handle;
}
@@ -2951,7 +3184,7 @@ setup_connection(struct buffer_instance *instance, struct common_record_context
struct tracecmd_msg_handle *msg_handle;
struct tracecmd_output *network_handle;
- msg_handle = setup_network();
+ msg_handle = setup_network(instance);
/* Now create the handle through this socket */
if (msg_handle->version == V3_PROTOCOL) {
@@ -2978,28 +3211,99 @@ static void finish_network(struct tracecmd_msg_handle *msg_handle)
free(host);
}
+static void connect_to_agent(struct buffer_instance *instance)
+{
+ struct tracecmd_msg_handle *msg_handle;
+ int sd, ret, nr_cpus, page_size;
+ unsigned int *ports;
+
+ sd = open_vsock(instance->cid, instance->port);
+ if (sd < 0)
+ die("Failed to connect to vsocket @%d:%d",
+ instance->cid, instance->port);
+
+ msg_handle = tracecmd_msg_handle_alloc(sd, 0);
+ if (!msg_handle)
+ die("Failed to allocate message handle");
+
+ ret = tracecmd_msg_send_trace_req(msg_handle, instance->argc, instance->argv);
+ if (ret < 0)
+ die("Failed to send trace request");
+
+ ret = tracecmd_msg_recv_trace_resp(msg_handle, &nr_cpus, &page_size, &ports);
+ if (ret < 0)
+ die("Failed to receive trace response");
+
+ instance->client_ports = ports;
+ instance->cpu_count = nr_cpus;
+
+ /* the msg_handle now points to the guest fd */
+ instance->msg_handle = msg_handle;
+}
+
+static void setup_guest(struct buffer_instance *instance)
+{
+ struct tracecmd_msg_handle *msg_handle = instance->msg_handle;
+ char *file;
+ int fd;
+
+ /* Create a place to store the guest meta data */
+ file = get_guest_file(output_file, instance->name);
+ if (!file)
+ die("Failed to allocate memory");
+
+ fd = open(file, O_CREAT|O_WRONLY|O_TRUNC, 0644);
+ put_temp_file(file);
+ if (fd < 0)
+ die("Failed to open", file);
+
+ /* Start reading tracing metadata */
+ if (tracecmd_msg_read_data(msg_handle, fd))
+ die("Failed receiving metadata");
+ close(fd);
+}
+
+static void setup_agent(struct buffer_instance *instance, struct common_record_context *ctx)
+{
+ struct tracecmd_output *network_handle;
+
+ network_handle = tracecmd_create_init_fd_msg(instance->msg_handle,
+ listed_events);
+ add_options(network_handle, ctx);
+ tracecmd_write_cpus(network_handle, instance->cpu_count);
+ tracecmd_write_options(network_handle);
+ tracecmd_msg_finish_sending_data(instance->msg_handle);
+ instance->network_handle = network_handle;
+}
+
void start_threads(enum trace_type type, struct common_record_context *ctx)
{
struct buffer_instance *instance;
- int *brass = NULL;
int total_cpu_count = 0;
int i = 0;
int ret;
- for_all_instances(instance)
+ for_all_instances(instance) {
+ /* Start the connection now to find out how many CPUs we need */
+ if (is_guest(instance))
+ connect_to_agent(instance);
total_cpu_count += instance->cpu_count;
+ }
/* make a thread for every CPU we have */
- pids = malloc(sizeof(*pids) * total_cpu_count * (buffers + 1));
+ pids = calloc(total_cpu_count * (buffers + 1), sizeof(*pids));
if (!pids)
- die("Failed to allocat pids for %d cpus", total_cpu_count);
-
- memset(pids, 0, sizeof(*pids) * total_cpu_count * (buffers + 1));
+ die("Failed to allocate pids for %d cpus", total_cpu_count);
for_all_instances(instance) {
+ int *brass = NULL;
int x, pid;
- if (host) {
+ if (is_agent(instance)) {
+ setup_agent(instance, ctx);
+ } else if (is_guest(instance)) {
+ setup_guest(instance);
+ } else if (host) {
instance->msg_handle = setup_connection(instance, ctx);
if (!instance->msg_handle)
die("Failed to make connection");
@@ -3172,7 +3476,44 @@ static void add_options(struct tracecmd_output *handle, struct common_record_con
tracecmd_add_option(handle, TRACECMD_OPTION_TRACECLOCK, 0, NULL);
add_option_hooks(handle);
add_uname(handle);
+}
+static void write_guest_file(struct buffer_instance *instance)
+{
+ struct tracecmd_output *handle;
+ int cpu_count = instance->cpu_count;
+ char *file;
+ char **temp_files;
+ int i, fd;
+
+ file = get_guest_file(output_file, instance->name);
+ fd = open(file, O_RDWR);
+ if (fd < 0)
+ die("error opening %s", file);
+ put_temp_file(file);
+
+ handle = tracecmd_get_output_handle_fd(fd);
+ if (!handle)
+ die("error writing to %s", file);
+
+ temp_files = malloc(sizeof(*temp_files) * cpu_count);
+ if (!temp_files)
+ die("failed to allocate temp_files for %d cpus",
+ cpu_count);
+
+ for (i = 0; i < cpu_count; i++) {
+ temp_files[i] = get_temp_file(instance, i);
+ if (!temp_files[i])
+ die("failed to allocate memory");
+ }
+
+ if (tracecmd_write_cpu_data(handle, cpu_count, temp_files) < 0)
+ die("failed to write CPU data");
+ tracecmd_output_close(handle);
+
+ for (i = 0; i < cpu_count; i++)
+ put_temp_file(temp_files[i]);
+ free(temp_files);
}
static void record_data(struct common_record_context *ctx)
@@ -3186,7 +3527,9 @@ static void record_data(struct common_record_context *ctx)
int i;
for_all_instances(instance) {
- if (instance->msg_handle)
+ if (is_guest(instance))
+ write_guest_file(instance);
+ else if (host && instance->msg_handle)
finish_network(instance->msg_handle);
else
local = true;
@@ -4405,6 +4748,7 @@ void trace_stop(int argc, char **argv)
c = getopt(argc-1, argv+1, "hatB:");
if (c == -1)
break;
+
switch (c) {
case 'h':
usage(argv);
@@ -4567,6 +4911,65 @@ static void init_common_record_context(struct common_record_context *ctx,
#define IS_STREAM(ctx) ((ctx)->curr_cmd == CMD_stream)
#define IS_PROFILE(ctx) ((ctx)->curr_cmd == CMD_profile)
#define IS_RECORD(ctx) ((ctx)->curr_cmd == CMD_record)
+#define IS_RECORD_AGENT(ctx) ((ctx)->curr_cmd == CMD_record_agent)
+
+static void add_argv(struct buffer_instance *instance, char *arg, bool prepend)
+{
+ instance->argv = realloc(instance->argv,
+ (instance->argc + 1) * sizeof(char *));
+ if (!instance->argv)
+ die("Can not allocate instance args");
+ if (prepend) {
+ memmove(instance->argv + 1, instance->argv,
+ instance->argc * sizeof(*instance->argv));
+ instance->argv[0] = arg;
+ } else {
+ instance->argv[instance->argc] = arg;
+ }
+ instance->argc++;
+}
+
+static void add_arg(struct buffer_instance *instance,
+ int c, const char *opts,
+ struct option *long_options, char *optarg)
+{
+ char *ptr, *arg;
+ int i, ret;
+
+ /* Short or long arg */
+ if (!(c & 0x80)) {
+ ptr = strchr(opts, c);
+ if (!ptr)
+ return; /* Not found? */
+ ret = asprintf(&arg, "-%c", c);
+ if (ret < 0)
+ die("Can not allocate argument");
+ add_argv(instance, arg, false);
+ if (ptr[1] == ':') {
+ arg = strdup(optarg);
+ if (!arg)
+ die("Can not allocate arguments");
+ add_argv(instance, arg, false);
+ }
+ return;
+ }
+ for (i = 0; long_options[i].name; i++) {
+ if (c != long_options[i].val)
+ continue;
+ ret = asprintf(&arg, "--%s", long_options[i].name);
+ if (ret < 0)
+ die("Can not allocate argument");
+ add_argv(instance, arg, false);
+ if (long_options[i].has_arg) {
+ arg = strdup(optarg);
+ if (!arg)
+ die("Can not allocate arguments");
+ add_argv(instance, arg, false);
+ }
+ return;
+ }
+ /* Not found? */
+}
static void parse_record_options(int argc,
char **argv,
@@ -4608,10 +5011,20 @@ static void parse_record_options(int argc,
if (IS_EXTRACT(ctx))
opts = "+haf:Fp:co:O:sr:g:l:n:P:N:tb:B:ksiT";
else
- opts = "+hae:f:Fp:cC:dDGo:O:s:r:vg:l:n:P:N:tb:R:B:ksSiTm:M:H:q";
+ opts = "+hae:f:FA:p:cC:dDGo:O:s:r:vg:l:n:P:N:tb:R:B:ksSiTm:M:H:q";
c = getopt_long (argc-1, argv+1, opts, long_options, &option_index);
if (c == -1)
break;
+
+ /*
+ * If the current instance is to record a guest, then save
+ * all the arguments for this instance.
+ */
+ if (c != 'B' && c != 'A' && is_guest(ctx->instance)) {
+ add_arg(ctx->instance, c, opts, long_options, optarg);
+ continue;
+ }
+
switch (c) {
case 'h':
usage(argv);
@@ -4664,6 +5077,26 @@ static void parse_record_options(int argc,
add_trigger(event, optarg);
break;
+ case 'A': {
+ char *name = NULL;
+ int cid = -1, port = -1;
+
+ if (!IS_RECORD(ctx))
+ die("-A is only allowed for record operations");
+
+ name = parse_guest_name(optarg, &cid, &port);
+ if (!name || cid == -1)
+ die("guest %s not found", optarg);
+ if (port == -1)
+ port = TRACE_AGENT_DEFAULT_PORT;
+
+ ctx->instance = create_instance(name);
+ ctx->instance->flags |= BUFFER_FL_GUEST;
+ ctx->instance->cid = cid;
+ ctx->instance->port = port;
+ add_instance(ctx->instance, 0);
+ break;
+ }
case 'F':
test_set_event_pid();
filter_task = 1;
@@ -4734,6 +5167,8 @@ static void parse_record_options(int argc,
ctx->disable = 1;
break;
case 'o':
+ if (IS_RECORD_AGENT(ctx))
+ die("-o incompatible with agent recording");
if (host)
die("-o incompatible with -N");
if (IS_START(ctx))
@@ -4795,6 +5230,8 @@ static void parse_record_options(int argc,
case 'N':
if (!IS_RECORD(ctx))
die("-N only available with record");
+ if (IS_RECORD_AGENT(ctx))
+ die("-N incompatible with agent recording");
if (ctx->output)
die("-N incompatible with -o");
host = optarg;
@@ -4891,6 +5328,16 @@ static void parse_record_options(int argc,
}
}
+ /* If --date is specified, prepend it to all guest VM flags */
+ if (ctx->date) {
+ struct buffer_instance *instance;
+
+ for_all_instances(instance) {
+ if (is_guest(instance))
+ add_argv(instance, "--date", true);
+ }
+ }
+
if (!ctx->filtered && ctx->instance->filter_mod)
add_func(&ctx->instance->filter_funcs,
ctx->instance->filter_mod, "*");
@@ -4921,7 +5368,8 @@ static enum trace_type get_trace_cmd_type(enum trace_cmd cmd)
{CMD_stream, TRACE_TYPE_STREAM},
{CMD_extract, TRACE_TYPE_EXTRACT},
{CMD_profile, TRACE_TYPE_STREAM},
- {CMD_start, TRACE_TYPE_START}
+ {CMD_start, TRACE_TYPE_START},
+ {CMD_record_agent, TRACE_TYPE_RECORD}
};
for (int i = 0; i < ARRAY_SIZE(trace_type_per_command); i++) {
@@ -4953,12 +5401,28 @@ static void finalize_record_trace(struct common_record_context *ctx)
if (instance->flags & BUFFER_FL_KEEP)
write_tracing_on(instance,
instance->tracing_on_init_val);
+ if (is_agent(instance))
+ tracecmd_output_close(instance->network_handle);
}
if (host)
tracecmd_output_close(ctx->instance->network_handle);
}
+static bool has_local_instances(void)
+{
+ struct buffer_instance *instance;
+
+ for_all_instances(instance) {
+ if (is_guest(instance))
+ continue;
+ if (host && instance->msg_handle)
+ continue;
+ return true;
+ }
+ return false;
+}
+
/*
* This function contains common code for the following commands:
* record, start, stream, profile.
@@ -4987,7 +5451,6 @@ static void record_trace(int argc, char **argv,
/* Save the state of tracing_on before starting */
for_all_instances(instance) {
-
if (!ctx->manual && instance->flags & BUFFER_FL_PROFILE)
enable_profile(instance);
@@ -5004,14 +5467,16 @@ static void record_trace(int argc, char **argv,
page_size = getpagesize();
- fset = set_ftrace(!ctx->disable, ctx->total_disable);
+ if (!is_guest(ctx->instance))
+ fset = set_ftrace(!ctx->disable, ctx->total_disable);
tracecmd_disable_all_tracing(1);
for_all_instances(instance)
set_clock(instance);
/* Record records the date first */
- if (IS_RECORD(ctx) && ctx->date)
+ if (ctx->date &&
+ ((IS_RECORD(ctx) && has_local_instances()) || IS_RECORD_AGENT(ctx)))
ctx->date2ts = get_date_to_ts();
for_all_instances(instance) {
@@ -5046,9 +5511,13 @@ static void record_trace(int argc, char **argv,
exit(0);
}
- if (ctx->run_command)
+ if (ctx->run_command) {
run_cmd(type, (argc - optind) - 1, &argv[optind + 1]);
- else {
+ } else if (ctx->instance && is_agent(ctx->instance)) {
+ update_task_filter();
+ tracecmd_enable_tracing();
+ tracecmd_msg_wait_close(ctx->instance->msg_handle);
+ } else {
update_task_filter();
tracecmd_enable_tracing();
/* We don't ptrace ourself */
@@ -5060,6 +5529,7 @@ static void record_trace(int argc, char **argv,
trace_or_sleep(type);
}
+ tell_guests_to_stop();
tracecmd_disable_tracing();
if (!latency)
stop_threads(type);
@@ -5069,6 +5539,9 @@ static void record_trace(int argc, char **argv,
if (!keep)
tracecmd_disable_all_tracing(0);
+ if (!latency)
+ wait_threads();
+
if (IS_RECORD(ctx)) {
record_data(ctx);
delete_thread_data();
@@ -5203,3 +5676,40 @@ void trace_record(int argc, char **argv)
record_trace(argc, argv, &ctx);
exit(0);
}
+
+int trace_record_agent(struct tracecmd_msg_handle *msg_handle,
+ int cpus, int *fds,
+ int argc, char **argv)
+{
+ struct common_record_context ctx;
+ char **argv_plus;
+
+ /* Reset optind for getopt_long */
+ optind = 1;
+ /*
+ * argc is the number of elements in argv, but we need to convert
+ * argc and argv into "trace-cmd", "record", argv.
+ * where argc needs to grow by two.
+ */
+ argv_plus = calloc(argc + 2, sizeof(char *));
+ if (!argv_plus)
+ return -ENOMEM;
+
+ argv_plus[0] = "trace-cmd";
+ argv_plus[1] = "record";
+ memmove(argv_plus + 2, argv, argc * sizeof(char *));
+ argc += 2;
+
+ parse_record_options(argc, argv_plus, CMD_record_agent, &ctx);
+ if (ctx.run_command)
+ return -EINVAL;
+
+ ctx.instance->fds = fds;
+ ctx.instance->flags |= BUFFER_FL_AGENT;
+ ctx.instance->msg_handle = msg_handle;
+ msg_handle->version = V3_PROTOCOL;
+ record_trace(argc, argv, &ctx);
+
+ free(argv_plus);
+ return 0;
+}
diff --git a/tracecmd/trace-usage.c b/tracecmd/trace-usage.c
index 9ea1906..e845f50 100644
--- a/tracecmd/trace-usage.c
+++ b/tracecmd/trace-usage.c
@@ -231,11 +231,22 @@ static struct usage_help usage_help[] = {
"listen on a network socket for trace clients",
" %s listen -p port[-D][-o file][-d dir][-l logfile]\n"
" Creates a socket to listen for clients.\n"
- " -D create it in daemon mode.\n"
+ " -p port number to listen on.\n"
+ " -D run in daemon mode.\n"
" -o file name to use for clients.\n"
" -d directory to store client files.\n"
" -l logfile to write messages to.\n"
},
+#ifdef VSOCK
+ {
+ "agent",
+ "listen on a vsocket for trace clients",
+ " %s agent -p port[-D]\n"
+ " Creates a vsocket to listen for clients.\n"
+ " -p port number to listen on.\n"
+ " -D run in daemon mode.\n"
+ },
+#endif
{
"list",
"list the available events, plugins or options",
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 08/13] trace-cmd: Use splice(2) for vsockets if available
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
` (6 preceding siblings ...)
2019-02-18 14:54 ` [RFC PATCH v7 07/13] trace-cmd: Add VM kernel tracing over vsockets transport Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 09/13] trace-cmd: Add `trace-cmd setup-guest` command Slavomir Kaslev
` (4 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
Detect if splice(2) reading is supported for vsockets (Linux 4.20 and
later) and use it, or fallback to read/write-ing otherwise.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
lib/trace-cmd/trace-recorder.c | 6 ++--
tracecmd/trace-record.c | 56 ++++++++++++++++++++++++++++++++--
2 files changed, 56 insertions(+), 6 deletions(-)
diff --git a/lib/trace-cmd/trace-recorder.c b/lib/trace-cmd/trace-recorder.c
index 1b84bb5..d66f112 100644
--- a/lib/trace-cmd/trace-recorder.c
+++ b/lib/trace-cmd/trace-recorder.c
@@ -386,10 +386,8 @@ static long splice_data(struct tracecmd_recorder *recorder)
ret = splice(recorder->brass[0], NULL, recorder->fd, NULL,
read, recorder->fd_flags);
if (ret < 0) {
- if (errno != EAGAIN && errno != EINTR) {
- warning("recorder error in splice output");
- return -1;
- }
+ if (errno != EAGAIN && errno != EINTR)
+ return ret;
return total_read;
} else
update_fd(recorder, ret);
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index b401fd9..ca97758 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -2660,12 +2660,61 @@ static int open_vsock(unsigned int cid, unsigned int port)
return sd;
}
+
+static int try_splice_read_vsock(void)
+{
+ int ret, sd, brass[2];
+
+ sd = socket(AF_VSOCK, SOCK_STREAM, 0);
+ if (sd < 0)
+ return sd;
+
+ ret = pipe(brass);
+ if (ret < 0)
+ goto out_close_sd;
+
+ /*
+ * On kernels that don't support splice reading from vsockets
+ * this will fail with EINVAL, or ENOTCONN otherwise.
+ * Technically, it should never succeed but if it does, claim splice
+ * reading is supported.
+ */
+ ret = splice(sd, NULL, brass[1], NULL, 10, 0);
+ if (ret < 0)
+ ret = errno != EINVAL;
+ else
+ ret = 1;
+
+ close(brass[0]);
+ close(brass[1]);
+out_close_sd:
+ close(sd);
+ return ret;
+}
+
+static bool can_splice_read_vsock(void)
+{
+ static bool initialized, res;
+
+ if (initialized)
+ return res;
+
+ res = try_splice_read_vsock() > 0;
+ initialized = true;
+ return res;
+}
+
#else
static inline int open_vsock(unsigned int cid, unsigned int port)
{
die("vsock is not supported");
return -1;
}
+
+static bool can_splice_read_vsock(void)
+{
+ return false;
+}
#endif
static int do_accept(int sd)
@@ -2870,13 +2919,16 @@ create_recorder_instance(struct buffer_instance *instance, const char *file, int
if (is_guest(instance)) {
int fd;
+ unsigned int flags;
fd = open_vsock(instance->cid, instance->client_ports[cpu]);
if (fd < 0)
die("Failed to connect to agent");
- return tracecmd_create_recorder_virt(
- file, cpu, recorder_flags | TRACECMD_RECORD_NOSPLICE, fd);
+ flags = recorder_flags;
+ if (!can_splice_read_vsock())
+ flags |= TRACECMD_RECORD_NOSPLICE;
+ return tracecmd_create_recorder_virt(file, cpu, flags, fd);
}
if (brass)
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 09/13] trace-cmd: Add `trace-cmd setup-guest` command
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
` (7 preceding siblings ...)
2019-02-18 14:54 ` [RFC PATCH v7 08/13] trace-cmd: Use splice(2) for vsockets if available Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 10/13] trace-cmd: Try to autodetect number of guest CPUs in setup-guest if not specified Slavomir Kaslev
` (3 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
Add `trace-cmd setup-guest` command that creates the necessary FIFOs for tracing
a guest over FIFOs instead of vsockets.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
tracecmd/Makefile | 1 +
tracecmd/include/trace-local.h | 6 ++
tracecmd/trace-cmd.c | 1 +
tracecmd/trace-setup-guest.c | 176 +++++++++++++++++++++++++++++++++
tracecmd/trace-usage.c | 8 ++
5 files changed, 192 insertions(+)
create mode 100644 tracecmd/trace-setup-guest.c
diff --git a/tracecmd/Makefile b/tracecmd/Makefile
index 865b1c6..d3e3080 100644
--- a/tracecmd/Makefile
+++ b/tracecmd/Makefile
@@ -35,6 +35,7 @@ TRACE_CMD_OBJS += trace-msg.o
ifeq ($(VSOCK_DEFINED), 1)
TRACE_CMD_OBJS += trace-agent.o
+TRACE_CMD_OBJS += trace-setup-guest.o
endif
ALL_OBJS := $(TRACE_CMD_OBJS:%.o=$(bdir)/%.o)
diff --git a/tracecmd/include/trace-local.h b/tracecmd/include/trace-local.h
index 95cf512..d32ba88 100644
--- a/tracecmd/include/trace-local.h
+++ b/tracecmd/include/trace-local.h
@@ -14,6 +14,10 @@
#define TRACE_AGENT_DEFAULT_PORT 823
+#define GUEST_PIPE_NAME "trace-pipe-cpu"
+#define GUEST_DIR_FMT "/var/lib/trace-cmd/virt/%s"
+#define GUEST_FIFO_FMT GUEST_DIR_FMT "/" GUEST_PIPE_NAME "%d"
+
extern int debug;
extern int quiet;
@@ -68,6 +72,8 @@ void trace_listen(int argc, char **argv);
void trace_agent(int argc, char **argv);
+void trace_setup_guest(int argc, char **argv);
+
void trace_restore(int argc, char **argv);
void trace_clear(int argc, char **argv);
diff --git a/tracecmd/trace-cmd.c b/tracecmd/trace-cmd.c
index 3ae5e2e..4da82b4 100644
--- a/tracecmd/trace-cmd.c
+++ b/tracecmd/trace-cmd.c
@@ -85,6 +85,7 @@ struct command commands[] = {
{"listen", trace_listen},
#ifdef VSOCK
{"agent", trace_agent},
+ {"setup-guest", trace_setup_guest},
#endif
{"split", trace_split},
{"restore", trace_restore},
diff --git a/tracecmd/trace-setup-guest.c b/tracecmd/trace-setup-guest.c
new file mode 100644
index 0000000..ded510e
--- /dev/null
+++ b/tracecmd/trace-setup-guest.c
@@ -0,0 +1,176 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 VMware Inc, Slavomir Kaslev <kaslevs@vmware.com>
+ *
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <grp.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "trace-local.h"
+#include "trace-msg.h"
+
+static int make_dir(const char *path, mode_t mode)
+{
+ char buf[PATH_MAX+1], *end, *p;
+
+ end = stpncpy(buf, path, sizeof(buf));
+ for (p = buf; p < end; p++) {
+ for (; p < end && *p == '/'; p++);
+ for (; p < end && *p != '/'; p++);
+
+ *p = '\0';
+ if (mkdir(buf, mode) < 0 && errno != EEXIST)
+ return -errno;
+ *p = '/';
+ }
+
+ return 0;
+}
+
+static int make_fifo(const char *path, mode_t mode)
+{
+ struct stat st;
+ int ret;
+
+ ret = stat(path, &st);
+ if (ret == 0) {
+ if (S_ISFIFO(st.st_mode))
+ return 0;
+ return -EEXIST;
+ }
+
+ return mkfifo(path, mode);
+}
+
+static int make_guest_dir(const char *guest)
+{
+ char path[PATH_MAX];
+
+ snprintf(path, sizeof(path), GUEST_DIR_FMT, guest);
+ return make_dir(path, 0750);
+}
+
+static int make_guest_fifo(const char *guest, int cpu, mode_t mode)
+{
+ static const char *exts[] = {".in", ".out"};
+ char path[PATH_MAX];
+ int i, ret = 0;
+
+ for (i = 0; i < ARRAY_SIZE(exts); i++) {
+ snprintf(path, sizeof(path), GUEST_FIFO_FMT "%s",
+ guest, cpu, exts[i]);
+ ret = make_fifo(path, mode);
+ if (ret < 0)
+ break;
+ }
+
+ return ret;
+}
+
+static int make_guest_fifos(const char *guest, int nr_cpus, mode_t mode)
+{
+ int i, ret = 0;
+ mode_t mask;
+
+ mask = umask(0);
+ for (i = 0; i < nr_cpus; i++) {
+ ret = make_guest_fifo(guest, i, mode);
+ if (ret < 0)
+ break;
+ }
+ umask(mask);
+
+ return ret;
+}
+
+static void do_setup_guest(const char *guest, int nr_cpus, mode_t mode, gid_t gid)
+{
+ gid_t save_egid;
+ int ret;
+
+ if (gid != -1) {
+ save_egid = getegid();
+ ret = setegid(gid);
+ if (ret < 0)
+ pdie("failed to set effective group ID");
+ }
+
+ ret = make_guest_dir(guest);
+ if (ret < 0)
+ pdie("failed to create guest directory for %s", guest);
+
+ ret = make_guest_fifos(guest, nr_cpus, mode);
+ if (ret < 0)
+ pdie("failed to create FIFOs for %s", guest);
+
+ if (gid != -1) {
+ ret = setegid(save_egid);
+ if (ret < 0)
+ pdie("failed to restore effective group ID");
+ }
+}
+
+void trace_setup_guest(int argc, char **argv)
+{
+ struct group *group;
+ mode_t mode = 0660;
+ int nr_cpus = -1;
+ gid_t gid = -1;
+ char *guest;
+
+ if (argc < 2)
+ usage(argv);
+
+ if (strcmp(argv[1], "setup-guest") != 0)
+ usage(argv);
+
+ for (;;) {
+ int c, option_index = 0;
+ static struct option long_options[] = {
+ {"help", no_argument, NULL, '?'},
+ {NULL, 0, NULL, 0}
+ };
+
+ c = getopt_long(argc-1, argv+1, "+hc:p:g:",
+ long_options, &option_index);
+ if (c == -1)
+ break;
+ switch (c) {
+ case 'h':
+ usage(argv);
+ break;
+ case 'c':
+ nr_cpus = atoi(optarg);
+ break;
+ case 'p':
+ mode = strtol(optarg, NULL, 8);
+ break;
+ case 'g':
+ group = getgrnam(optarg);
+ if (!group)
+ pdie("group %s does not exist", optarg);
+ gid = group->gr_gid;
+ break;
+ default:
+ usage(argv);
+ }
+ }
+
+ if (optind != argc-2)
+ usage(argv);
+
+ guest = argv[optind+1];
+
+ if (nr_cpus <= 0)
+ pdie("invalid number of cpus for guest %s", guest);
+
+ do_setup_guest(guest, nr_cpus, mode, gid);
+}
diff --git a/tracecmd/trace-usage.c b/tracecmd/trace-usage.c
index e845f50..7a8002f 100644
--- a/tracecmd/trace-usage.c
+++ b/tracecmd/trace-usage.c
@@ -246,6 +246,14 @@ static struct usage_help usage_help[] = {
" -p port number to listen on.\n"
" -D run in daemon mode.\n"
},
+ {
+ "setup-guest",
+ "create FIFOs for tracing guest VMs",
+ " %s setup-guest -c cpus[-p perm][-g group] guest\n"
+ " -c number of guest virtual CPUs\n"
+ " -p FIFOs permissions (default: 0660)\n"
+ " -g FIFOs group owner\n"
+ },
#endif
{
"list",
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 10/13] trace-cmd: Try to autodetect number of guest CPUs in setup-guest if not specified
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
` (8 preceding siblings ...)
2019-02-18 14:54 ` [RFC PATCH v7 09/13] trace-cmd: Add `trace-cmd setup-guest` command Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 11/13] trace-cmd: Add setup-guest flag for attaching FIFOs to the guest VM config Slavomir Kaslev
` (2 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
When no number of guest CPUs is provided with the -c flag to `trace-cmd
setup-guest`, try to autodetect it using virsh for libvirt managed guests.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
tracecmd/trace-setup-guest.c | 21 +++++++++++++++++++++
tracecmd/trace-usage.c | 2 +-
2 files changed, 22 insertions(+), 1 deletion(-)
diff --git a/tracecmd/trace-setup-guest.c b/tracecmd/trace-setup-guest.c
index ded510e..789dc65 100644
--- a/tracecmd/trace-setup-guest.c
+++ b/tracecmd/trace-setup-guest.c
@@ -91,6 +91,24 @@ static int make_guest_fifos(const char *guest, int nr_cpus, mode_t mode)
return ret;
}
+static int get_guest_cpu_count(const char *guest)
+{
+ const char *cmd_fmt = "virsh vcpucount --maximum '%s' 2>/dev/null";
+ int nr_cpus = -1;
+ char cmd[1024];
+ FILE *f;
+
+ snprintf(cmd, sizeof(cmd), cmd_fmt, guest);
+ f = popen(cmd, "r");
+ if (!f)
+ return -errno;
+
+ fscanf(f, "%d", &nr_cpus);
+ pclose(f);
+
+ return nr_cpus;
+}
+
static void do_setup_guest(const char *guest, int nr_cpus, mode_t mode, gid_t gid)
{
gid_t save_egid;
@@ -169,6 +187,9 @@ void trace_setup_guest(int argc, char **argv)
guest = argv[optind+1];
+ if (nr_cpus <= 0)
+ nr_cpus = get_guest_cpu_count(guest);
+
if (nr_cpus <= 0)
pdie("invalid number of cpus for guest %s", guest);
diff --git a/tracecmd/trace-usage.c b/tracecmd/trace-usage.c
index 7a8002f..9a13d93 100644
--- a/tracecmd/trace-usage.c
+++ b/tracecmd/trace-usage.c
@@ -249,7 +249,7 @@ static struct usage_help usage_help[] = {
{
"setup-guest",
"create FIFOs for tracing guest VMs",
- " %s setup-guest -c cpus[-p perm][-g group] guest\n"
+ " %s setup-guest [-c cpus][-p perm][-g group] guest\n"
" -c number of guest virtual CPUs\n"
" -p FIFOs permissions (default: 0660)\n"
" -g FIFOs group owner\n"
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 11/13] trace-cmd: Add setup-guest flag for attaching FIFOs to the guest VM config
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
` (9 preceding siblings ...)
2019-02-18 14:54 ` [RFC PATCH v7 10/13] trace-cmd: Try to autodetect number of guest CPUs in setup-guest if not specified Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 12/13] trace-cmd: Add splice() recording from FIFO without additional pipe buffer Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 13/13] trace-cmd: Add VM tracing over FIFOs transport Slavomir Kaslev
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
This patch adds a flag for attaching the newly created FIFOs for guest tracing
as virtio serial devices to libvirt managed guests.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
tracecmd/trace-setup-guest.c | 54 ++++++++++++++++++++++++++++++++++--
tracecmd/trace-usage.c | 3 +-
2 files changed, 53 insertions(+), 4 deletions(-)
diff --git a/tracecmd/trace-setup-guest.c b/tracecmd/trace-setup-guest.c
index 789dc65..043bca2 100644
--- a/tracecmd/trace-setup-guest.c
+++ b/tracecmd/trace-setup-guest.c
@@ -109,7 +109,45 @@ static int get_guest_cpu_count(const char *guest)
return nr_cpus;
}
-static void do_setup_guest(const char *guest, int nr_cpus, mode_t mode, gid_t gid)
+static int attach_guest_fifos(const char *guest, int nr_cpus)
+{
+ const char *cmd_fmt =
+ "virsh attach-device --config '%s' '%s' >/dev/null 2>/dev/null";
+ const char *xml_fmt =
+ "<channel type='pipe'>\n"
+ " <source path='%s'/>\n"
+ " <target type='virtio' name='%s%d'/>\n"
+ "</channel>";
+ char tmp_path[PATH_MAX], path[PATH_MAX];
+ char cmd[PATH_MAX], xml[PATH_MAX];
+ int i, fd, ret = 0;
+
+ strcpy(tmp_path, "/tmp/pipexmlXXXXXX");
+ fd = mkstemp(tmp_path);
+ if (fd < 0)
+ return fd;
+
+ for (i = 0; i < nr_cpus; i++) {
+ snprintf(path, sizeof(path), GUEST_FIFO_FMT, guest, i);
+ snprintf(xml, sizeof(xml), xml_fmt, path, GUEST_PIPE_NAME, i);
+ pwrite(fd, xml, strlen(xml), 0);
+
+ snprintf(cmd, sizeof(cmd), cmd_fmt, guest, tmp_path);
+ errno = 0;
+ if (system(cmd) != 0) {
+ ret = -errno;
+ break;
+ }
+ }
+
+ close(fd);
+ unlink(tmp_path);
+
+ return ret;
+}
+
+static void do_setup_guest(const char *guest, int nr_cpus,
+ mode_t mode, gid_t gid, bool attach)
{
gid_t save_egid;
int ret;
@@ -129,6 +167,12 @@ static void do_setup_guest(const char *guest, int nr_cpus, mode_t mode, gid_t gi
if (ret < 0)
pdie("failed to create FIFOs for %s", guest);
+ if (attach) {
+ ret = attach_guest_fifos(guest, nr_cpus);
+ if (ret < 0)
+ pdie("failed to attach FIFOs to %s", guest);
+ }
+
if (gid != -1) {
ret = setegid(save_egid);
if (ret < 0)
@@ -138,6 +182,7 @@ static void do_setup_guest(const char *guest, int nr_cpus, mode_t mode, gid_t gi
void trace_setup_guest(int argc, char **argv)
{
+ bool attach = false;
struct group *group;
mode_t mode = 0660;
int nr_cpus = -1;
@@ -157,7 +202,7 @@ void trace_setup_guest(int argc, char **argv)
{NULL, 0, NULL, 0}
};
- c = getopt_long(argc-1, argv+1, "+hc:p:g:",
+ c = getopt_long(argc-1, argv+1, "+hc:p:g:a",
long_options, &option_index);
if (c == -1)
break;
@@ -177,6 +222,9 @@ void trace_setup_guest(int argc, char **argv)
pdie("group %s does not exist", optarg);
gid = group->gr_gid;
break;
+ case 'a':
+ attach = true;
+ break;
default:
usage(argv);
}
@@ -193,5 +241,5 @@ void trace_setup_guest(int argc, char **argv)
if (nr_cpus <= 0)
pdie("invalid number of cpus for guest %s", guest);
- do_setup_guest(guest, nr_cpus, mode, gid);
+ do_setup_guest(guest, nr_cpus, mode, gid, attach);
}
diff --git a/tracecmd/trace-usage.c b/tracecmd/trace-usage.c
index 9a13d93..bcfd3dc 100644
--- a/tracecmd/trace-usage.c
+++ b/tracecmd/trace-usage.c
@@ -249,10 +249,11 @@ static struct usage_help usage_help[] = {
{
"setup-guest",
"create FIFOs for tracing guest VMs",
- " %s setup-guest [-c cpus][-p perm][-g group] guest\n"
+ " %s setup-guest [-c cpus][-p perm][-g group][-a] guest\n"
" -c number of guest virtual CPUs\n"
" -p FIFOs permissions (default: 0660)\n"
" -g FIFOs group owner\n"
+ " -a Attach FIFOs to guest VM config\n"
},
#endif
{
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 12/13] trace-cmd: Add splice() recording from FIFO without additional pipe buffer
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
` (10 preceding siblings ...)
2019-02-18 14:54 ` [RFC PATCH v7 11/13] trace-cmd: Add setup-guest flag for attaching FIFOs to the guest VM config Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
2019-02-18 14:54 ` [RFC PATCH v7 13/13] trace-cmd: Add VM tracing over FIFOs transport Slavomir Kaslev
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
When `trace-cmd record` is reading tracing data over FIFO we can do a direct
splice from the FIFO to the output file descriptor instead of doing two through
an additional pipe buffer. This patch implements specialized tracecmd_recorder
data transfer version for this case.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
include/trace-cmd/trace-cmd.h | 3 +-
lib/trace-cmd/trace-recorder.c | 70 ++++++++++++++++++++++++++++------
2 files changed, 61 insertions(+), 12 deletions(-)
diff --git a/include/trace-cmd/trace-cmd.h b/include/trace-cmd/trace-cmd.h
index 6a21e66..52962e9 100644
--- a/include/trace-cmd/trace-cmd.h
+++ b/include/trace-cmd/trace-cmd.h
@@ -270,8 +270,9 @@ struct tracecmd_output *tracecmd_get_output_handle_fd(int fd);
enum {
TRACECMD_RECORD_NOSPLICE = (1 << 0), /* Use read instead of splice */
- TRACECMD_RECORD_SNAPSHOT = (1 << 1), /* extract from snapshot */
+ TRACECMD_RECORD_SNAPSHOT = (1 << 1), /* Extract from snapshot */
TRACECMD_RECORD_BLOCK = (1 << 2), /* Block on splice write */
+ TRACECMD_RECORD_NOBRASS = (1 << 3), /* Splice directly without a brass pipe */
};
void tracecmd_free_recorder(struct tracecmd_recorder *recorder);
diff --git a/lib/trace-cmd/trace-recorder.c b/lib/trace-cmd/trace-recorder.c
index d66f112..8058d71 100644
--- a/lib/trace-cmd/trace-recorder.c
+++ b/lib/trace-cmd/trace-recorder.c
@@ -8,6 +8,7 @@
#include <stdlib.h>
#include <fcntl.h>
#include <time.h>
+#include <poll.h>
#include <unistd.h>
#include <errno.h>
@@ -26,6 +27,8 @@
# define SPLICE_F_GIFT 8
#endif
+#define POLL_TIMEOUT_MS 1000
+
struct tracecmd_recorder {
int fd;
int fd1;
@@ -40,6 +43,7 @@ struct tracecmd_recorder {
int pages;
int count;
unsigned fd_flags;
+ unsigned trace_fd_flags;
unsigned flags;
};
@@ -127,6 +131,8 @@ tracecmd_create_buffer_recorder_fd2(int fd, int fd2, int cpu, unsigned flags,
if (!(recorder->flags & TRACECMD_RECORD_BLOCK))
recorder->fd_flags |= SPLICE_F_NONBLOCK;
+ recorder->trace_fd_flags = SPLICE_F_MOVE;
+
/* Init to know what to free and release */
recorder->trace_fd = -1;
recorder->brass[0] = -1;
@@ -171,7 +177,8 @@ tracecmd_create_buffer_recorder_fd2(int fd, int fd2, int cpu, unsigned flags,
goto out_free;
}
- if ((recorder->flags & TRACECMD_RECORD_NOSPLICE) == 0) {
+ if (!(recorder->flags & (TRACECMD_RECORD_NOSPLICE |
+ TRACECMD_RECORD_NOBRASS))) {
ret = pipe(recorder->brass);
if (ret < 0)
goto out_free;
@@ -372,7 +379,7 @@ static long splice_data(struct tracecmd_recorder *recorder)
long ret;
read = splice(recorder->trace_fd, NULL, recorder->brass[1], NULL,
- recorder->pipe_size, SPLICE_F_MOVE);
+ recorder->pipe_size, recorder->trace_fd_flags);
if (read < 0) {
if (errno != EAGAIN && errno != EINTR) {
warning("recorder error in splice input");
@@ -399,6 +406,39 @@ static long splice_data(struct tracecmd_recorder *recorder)
return total_read;
}
+/*
+ * Returns -1 on error.
+ * or bytes of data read.
+ */
+static long direct_splice_data(struct tracecmd_recorder *recorder)
+{
+ struct pollfd pfd = {
+ .fd = recorder->trace_fd,
+ .events = POLLIN,
+ };
+ long read;
+ int ret;
+
+ ret = poll(&pfd, 1, POLL_TIMEOUT_MS);
+ if (ret < 0)
+ return -1;
+
+ if (!(pfd.revents | POLLIN))
+ return 0;
+
+ read = splice(recorder->trace_fd, NULL, recorder->fd, NULL,
+ recorder->pipe_size, recorder->trace_fd_flags);
+ if (read < 0) {
+ if (errno == EAGAIN || errno == EINTR)
+ return 0;
+
+ warning("recorder error in splice input");
+ return -1;
+ }
+
+ return read;
+}
+
/*
* Returns -1 on error.
* or bytes of data read.
@@ -433,6 +473,17 @@ static long read_data(struct tracecmd_recorder *recorder)
return r;
}
+static long move_data(struct tracecmd_recorder *recorder)
+{
+ if (recorder->flags & TRACECMD_RECORD_NOSPLICE)
+ return read_data(recorder);
+
+ if (recorder->flags & TRACECMD_RECORD_NOBRASS)
+ return direct_splice_data(recorder);
+
+ return splice_data(recorder);
+}
+
static void set_nonblock(struct tracecmd_recorder *recorder)
{
long flags;
@@ -440,8 +491,11 @@ static void set_nonblock(struct tracecmd_recorder *recorder)
/* Do not block on reads for flushing */
flags = fcntl(recorder->trace_fd, F_GETFL);
fcntl(recorder->trace_fd, F_SETFL, flags | O_NONBLOCK);
+ recorder->trace_fd_flags |= SPLICE_F_NONBLOCK;
- /* Do not block on streams for write */
+ /* Do not block on pipes for write */
+ flags = fcntl(recorder->fd, F_GETFL);
+ fcntl(recorder->fd, F_SETFL, flags | O_NONBLOCK);
recorder->fd_flags |= SPLICE_F_NONBLOCK;
}
@@ -455,10 +509,7 @@ long tracecmd_flush_recording(struct tracecmd_recorder *recorder)
set_nonblock(recorder);
do {
- if (recorder->flags & TRACECMD_RECORD_NOSPLICE)
- ret = read_data(recorder);
- else
- ret = splice_data(recorder);
+ ret = move_data(recorder);
if (ret < 0)
return ret;
total += ret;
@@ -503,10 +554,7 @@ int tracecmd_start_recording(struct tracecmd_recorder *recorder, unsigned long s
read = 0;
do {
- if (recorder->flags & TRACECMD_RECORD_NOSPLICE)
- ret = read_data(recorder);
- else
- ret = splice_data(recorder);
+ ret = move_data(recorder);
if (ret < 0)
return ret;
read += ret;
--
2.19.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [RFC PATCH v7 13/13] trace-cmd: Add VM tracing over FIFOs transport
2019-02-18 14:54 [RFC PATCH v7 00/13] Add VM kernel tracing over vsockets and FIFOs Slavomir Kaslev
` (11 preceding siblings ...)
2019-02-18 14:54 ` [RFC PATCH v7 12/13] trace-cmd: Add splice() recording from FIFO without additional pipe buffer Slavomir Kaslev
@ 2019-02-18 14:54 ` Slavomir Kaslev
12 siblings, 0 replies; 14+ messages in thread
From: Slavomir Kaslev @ 2019-02-18 14:54 UTC (permalink / raw)
To: rostedt, rostedt; +Cc: linux-trace-devel, slavomir.kaslev
FIFOs offer ~3x the throughput of vsockets. This patch adds support for using
FIFOs to stream tracing data back to the host when tracing VMs.
Signed-off-by: Slavomir Kaslev <kaslevs@vmware.com>
---
include/trace-cmd/trace-cmd.h | 8 ++--
tracecmd/include/trace-local.h | 4 +-
tracecmd/trace-agent.c | 40 ++++++++++++++--
tracecmd/trace-msg.c | 26 ++++++----
tracecmd/trace-record.c | 87 ++++++++++++++++++++++++++++++----
5 files changed, 137 insertions(+), 28 deletions(-)
diff --git a/include/trace-cmd/trace-cmd.h b/include/trace-cmd/trace-cmd.h
index 52962e9..27ba89d 100644
--- a/include/trace-cmd/trace-cmd.h
+++ b/include/trace-cmd/trace-cmd.h
@@ -333,16 +333,16 @@ bool tracecmd_msg_done(struct tracecmd_msg_handle *msg_handle);
void tracecmd_msg_set_done(struct tracecmd_msg_handle *msg_handle);
int tracecmd_msg_send_trace_req(struct tracecmd_msg_handle *msg_handle,
- int argc, char **argv);
+ int argc, char **argv, bool use_fifos);
int tracecmd_msg_recv_trace_req(struct tracecmd_msg_handle *msg_handle,
- int *argc, char ***argv);
+ int *argc, char ***argv, bool *use_fifos);
int tracecmd_msg_send_trace_resp(struct tracecmd_msg_handle *msg_handle,
int nr_cpus, int page_size,
- unsigned int *ports);
+ unsigned int *ports, bool use_fifos);
int tracecmd_msg_recv_trace_resp(struct tracecmd_msg_handle *msg_handle,
int *nr_cpus, int *page_size,
- unsigned int **ports);
+ unsigned int **ports, bool *use_fifos);
/* --- Plugin handling --- */
extern struct tep_plugin_option trace_ftrace_options[];
diff --git a/tracecmd/include/trace-local.h b/tracecmd/include/trace-local.h
index d32ba88..d7bdb1f 100644
--- a/tracecmd/include/trace-local.h
+++ b/tracecmd/include/trace-local.h
@@ -17,6 +17,7 @@
#define GUEST_PIPE_NAME "trace-pipe-cpu"
#define GUEST_DIR_FMT "/var/lib/trace-cmd/virt/%s"
#define GUEST_FIFO_FMT GUEST_DIR_FMT "/" GUEST_PIPE_NAME "%d"
+#define VIRTIO_FIFO_FMT "/dev/virtio-ports/" GUEST_PIPE_NAME "%d"
extern int debug;
extern int quiet;
@@ -100,7 +101,7 @@ void trace_usage(int argc, char **argv);
int trace_record_agent(struct tracecmd_msg_handle *msg_handle,
int cpus, int *fds,
- int argc, char **argv);
+ int argc, char **argv, bool use_fifos);
struct hook_list;
@@ -212,6 +213,7 @@ struct buffer_instance {
int cid;
int port;
int *fds;
+ bool use_fifos;
};
extern struct buffer_instance top_instance;
diff --git a/tracecmd/trace-agent.c b/tracecmd/trace-agent.c
index 0c0873b..7389f72 100644
--- a/tracecmd/trace-agent.c
+++ b/tracecmd/trace-agent.c
@@ -83,12 +83,39 @@ static void make_vsocks(int nr, int *fds, unsigned int *ports)
}
}
+static int open_agent_fifos(int nr_cpus, int *fds)
+{
+ char path[PATH_MAX];
+ int i, fd, ret = 0;
+
+ for (i = 0; i < nr_cpus; i++) {
+ snprintf(path, sizeof(path), VIRTIO_FIFO_FMT, i);
+ fd = open(path, O_WRONLY);
+ if (fd < 0) {
+ ret = -errno;
+ break;
+ }
+
+ fds[i] = fd;
+ }
+
+ if (!ret)
+ return ret;
+
+ /* We failed to open all FIFOs so clean up and return error */
+ while (--i >= 0)
+ close(fds[i]);
+
+ return ret;
+}
+
static void agent_handle(int sd, int nr_cpus, int page_size)
{
struct tracecmd_msg_handle *msg_handle;
unsigned int *ports;
char **argv = NULL;
int argc = 0;
+ bool use_fifos;
int *fds;
int ret;
@@ -101,17 +128,22 @@ static void agent_handle(int sd, int nr_cpus, int page_size)
if (!msg_handle)
die("Failed to allocate message handle");
- ret = tracecmd_msg_recv_trace_req(msg_handle, &argc, &argv);
+ ret = tracecmd_msg_recv_trace_req(msg_handle, &argc, &argv, &use_fifos);
if (ret < 0)
die("Failed to receive trace request");
- make_vsocks(nr_cpus, fds, ports);
+ if (use_fifos && open_agent_fifos(nr_cpus, fds))
+ use_fifos = false;
+
+ if (!use_fifos)
+ make_vsocks(nr_cpus, fds, ports);
- ret = tracecmd_msg_send_trace_resp(msg_handle, nr_cpus, page_size, ports);
+ ret = tracecmd_msg_send_trace_resp(msg_handle, nr_cpus, page_size,
+ ports, use_fifos);
if (ret < 0)
die("Failed to send trace response");
- trace_record_agent(msg_handle, nr_cpus, fds, argc, argv);
+ trace_record_agent(msg_handle, nr_cpus, fds, argc, argv, use_fifos);
free(argv[0]);
free(argv);
diff --git a/tracecmd/trace-msg.c b/tracecmd/trace-msg.c
index 8ce1f98..065a01e 100644
--- a/tracecmd/trace-msg.c
+++ b/tracecmd/trace-msg.c
@@ -159,6 +159,10 @@ static int msg_write(int fd, struct tracecmd_msg *msg)
return __do_write_check(fd, msg->buf, data_size);
}
+enum msg_trace_flags {
+ MSG_TRACE_USE_FIFOS = 1 << 0,
+};
+
enum msg_opt_command {
MSGOPT_USETCP = 1,
};
@@ -740,7 +744,7 @@ error:
return ret;
}
-static int make_trace_req(struct tracecmd_msg *msg, int argc, char **argv)
+static int make_trace_req(struct tracecmd_msg *msg, int argc, char **argv, bool use_fifos)
{
size_t args_size = 0;
char *p;
@@ -750,6 +754,7 @@ static int make_trace_req(struct tracecmd_msg *msg, int argc, char **argv)
args_size += strlen(argv[i]) + 1;
msg->hdr.size = htonl(ntohl(msg->hdr.size) + args_size);
+ msg->trace_req.flags = use_fifos ? htonl(MSG_TRACE_USE_FIFOS) : htonl(0);
msg->trace_req.argc = htonl(argc);
msg->buf = calloc(args_size, 1);
if (!msg->buf)
@@ -763,13 +768,13 @@ static int make_trace_req(struct tracecmd_msg *msg, int argc, char **argv)
}
int tracecmd_msg_send_trace_req(struct tracecmd_msg_handle *msg_handle,
- int argc, char **argv)
+ int argc, char **argv, bool use_fifos)
{
struct tracecmd_msg msg;
int ret;
tracecmd_msg_init(MSG_TRACE_REQ, &msg);
- ret = make_trace_req(&msg, argc, argv);
+ ret = make_trace_req(&msg, argc, argv, use_fifos);
if (ret < 0)
return ret;
@@ -782,7 +787,7 @@ int tracecmd_msg_send_trace_req(struct tracecmd_msg_handle *msg_handle,
* free(argv);
*/
int tracecmd_msg_recv_trace_req(struct tracecmd_msg_handle *msg_handle,
- int *argc, char ***argv)
+ int *argc, char ***argv, bool *use_fifos)
{
struct tracecmd_msg msg;
char *p, *buf_end, **args;
@@ -834,6 +839,7 @@ int tracecmd_msg_recv_trace_req(struct tracecmd_msg_handle *msg_handle,
*argc = nr_args;
*argv = args;
+ *use_fifos = ntohl(msg.trace_req.flags) & MSG_TRACE_USE_FIFOS;
/*
* On success we're passing msg.buf to the caller through argv[0] so we
@@ -853,13 +859,14 @@ out:
return ret;
}
-static int make_trace_resp(struct tracecmd_msg *msg,
- int page_size, int nr_cpus, unsigned int *ports)
+static int make_trace_resp(struct tracecmd_msg *msg, int page_size, int nr_cpus,
+ unsigned int *ports, bool use_fifos)
{
int ports_size = nr_cpus * sizeof(*msg->port_array);
int i;
msg->hdr.size = htonl(ntohl(msg->hdr.size) + ports_size);
+ msg->trace_resp.flags = use_fifos ? htonl(MSG_TRACE_USE_FIFOS) : htonl(0);
msg->trace_resp.cpus = htonl(nr_cpus);
msg->trace_resp.page_size = htonl(page_size);
@@ -875,13 +882,13 @@ static int make_trace_resp(struct tracecmd_msg *msg,
int tracecmd_msg_send_trace_resp(struct tracecmd_msg_handle *msg_handle,
int nr_cpus, int page_size,
- unsigned int *ports)
+ unsigned int *ports, bool use_fifos)
{
struct tracecmd_msg msg;
int ret;
tracecmd_msg_init(MSG_TRACE_RESP, &msg);
- ret = make_trace_resp(&msg, page_size, nr_cpus, ports);
+ ret = make_trace_resp(&msg, page_size, nr_cpus, ports, use_fifos);
if (ret < 0)
return ret;
@@ -890,7 +897,7 @@ int tracecmd_msg_send_trace_resp(struct tracecmd_msg_handle *msg_handle,
int tracecmd_msg_recv_trace_resp(struct tracecmd_msg_handle *msg_handle,
int *nr_cpus, int *page_size,
- unsigned int **ports)
+ unsigned int **ports, bool *use_fifos)
{
struct tracecmd_msg msg;
ssize_t buf_len;
@@ -912,6 +919,7 @@ int tracecmd_msg_recv_trace_resp(struct tracecmd_msg_handle *msg_handle,
goto out;
}
+ *use_fifos = ntohl(msg.trace_resp.flags) & MSG_TRACE_USE_FIFOS;
*nr_cpus = ntohl(msg.trace_resp.cpus);
*page_size = ntohl(msg.trace_resp.page_size);
*ports = calloc(*nr_cpus, sizeof(**ports));
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index ca97758..ef6319f 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -76,6 +76,8 @@ static int buffers;
/* Clear all function filters */
static int clear_function_filters;
+static bool no_fifos;
+
static char *host;
/* Max size to let a per cpu file get */
@@ -2921,12 +2923,17 @@ create_recorder_instance(struct buffer_instance *instance, const char *file, int
int fd;
unsigned int flags;
- fd = open_vsock(instance->cid, instance->client_ports[cpu]);
+ if (instance->use_fifos)
+ fd = instance->fds[cpu];
+ else
+ fd = open_vsock(instance->cid, instance->client_ports[cpu]);
if (fd < 0)
die("Failed to connect to agent");
flags = recorder_flags;
- if (!can_splice_read_vsock())
+ if (instance->use_fifos)
+ flags |= TRACECMD_RECORD_NOBRASS;
+ else if (!can_splice_read_vsock())
flags |= TRACECMD_RECORD_NOSPLICE;
return tracecmd_create_recorder_virt(file, cpu, flags, fd);
}
@@ -2979,10 +2986,14 @@ static int create_recorder(struct buffer_instance *instance, int cpu,
char *path = NULL;
int fd;
- if (is_agent(instance))
- fd = do_accept(instance->fds[cpu]);
- else
+ if (is_agent(instance)) {
+ if (instance->use_fifos)
+ fd = instance->fds[cpu];
+ else
+ fd = do_accept(instance->fds[cpu]);
+ } else {
fd = connect_port(host, instance->client_ports[cpu]);
+ }
if (fd < 0)
die("Failed connecting to client");
if (instance->name && !is_agent(instance))
@@ -3263,11 +3274,42 @@ static void finish_network(struct tracecmd_msg_handle *msg_handle)
free(host);
}
+static int open_guest_fifos(const char *guest, int **fds)
+{
+ char path[PATH_MAX];
+ int i, fd, flags;
+
+ for (i = 0; ; i++) {
+ snprintf(path, sizeof(path), GUEST_FIFO_FMT ".out", guest, i);
+
+ /* O_NONBLOCK so we don't wait for writers */
+ fd = open(path, O_RDONLY | O_NONBLOCK);
+ if (fd < 0)
+ break;
+
+ /* Success, now clear O_NONBLOCK */
+ flags = fcntl(fd, F_GETFL);
+ fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
+
+ *fds = realloc(*fds, i + 1);
+ (*fds)[i] = fd;
+ }
+
+ return i;
+}
+
static void connect_to_agent(struct buffer_instance *instance)
{
struct tracecmd_msg_handle *msg_handle;
- int sd, ret, nr_cpus, page_size;
+ int sd, ret, nr_fifos, nr_cpus, page_size;
unsigned int *ports;
+ int i, *fds = NULL;
+ bool use_fifos = false;
+
+ if (!no_fifos) {
+ nr_fifos = open_guest_fifos(instance->name, &fds);
+ use_fifos = nr_fifos > 0;
+ }
sd = open_vsock(instance->cid, instance->port);
if (sd < 0)
@@ -3278,15 +3320,33 @@ static void connect_to_agent(struct buffer_instance *instance)
if (!msg_handle)
die("Failed to allocate message handle");
- ret = tracecmd_msg_send_trace_req(msg_handle, instance->argc, instance->argv);
+ ret = tracecmd_msg_send_trace_req(msg_handle, instance->argc,
+ instance->argv, use_fifos);
if (ret < 0)
die("Failed to send trace request");
- ret = tracecmd_msg_recv_trace_resp(msg_handle, &nr_cpus, &page_size, &ports);
+ ret = tracecmd_msg_recv_trace_resp(msg_handle, &nr_cpus, &page_size,
+ &ports, &use_fifos);
if (ret < 0)
die("Failed to receive trace response");
- instance->client_ports = ports;
+ if (use_fifos) {
+ if (nr_cpus != nr_fifos) {
+ warning("number of FIFOs (%d) for guest %s differs "
+ "from number of virtual CPUs (%d)",
+ nr_fifos, instance->name, nr_cpus);
+ nr_cpus = nr_cpus < nr_fifos ? nr_cpus : nr_fifos;
+ }
+ free(ports);
+ instance->fds = fds;
+ } else {
+ for (i = 0; i < nr_fifos; i++)
+ close(fds[i]);
+ free(fds);
+ instance->client_ports = ports;
+ }
+
+ instance->use_fifos = use_fifos;
instance->cpu_count = nr_cpus;
/* the msg_handle now points to the guest fd */
@@ -4785,6 +4845,7 @@ enum {
OPT_funcstack = 254,
OPT_date = 255,
OPT_module = 256,
+ OPT_nofifos = 257,
};
void trace_stop(int argc, char **argv)
@@ -5048,6 +5109,7 @@ static void parse_record_options(int argc,
{"date", no_argument, NULL, OPT_date},
{"func-stack", no_argument, NULL, OPT_funcstack},
{"nosplice", no_argument, NULL, OPT_nosplice},
+ {"nofifos", no_argument, NULL, OPT_nofifos},
{"profile", no_argument, NULL, OPT_profile},
{"stderr", no_argument, NULL, OPT_stderr},
{"by-comm", no_argument, NULL, OPT_bycomm},
@@ -5333,6 +5395,9 @@ static void parse_record_options(int argc,
case OPT_nosplice:
recorder_flags |= TRACECMD_RECORD_NOSPLICE;
break;
+ case OPT_nofifos:
+ no_fifos = true;
+ break;
case OPT_profile:
handle_init = trace_init_profile;
ctx->instance->flags |= BUFFER_FL_PROFILE;
@@ -5731,7 +5796,8 @@ void trace_record(int argc, char **argv)
int trace_record_agent(struct tracecmd_msg_handle *msg_handle,
int cpus, int *fds,
- int argc, char **argv)
+ int argc, char **argv,
+ bool use_fifos)
{
struct common_record_context ctx;
char **argv_plus;
@@ -5757,6 +5823,7 @@ int trace_record_agent(struct tracecmd_msg_handle *msg_handle,
return -EINVAL;
ctx.instance->fds = fds;
+ ctx.instance->use_fifos = use_fifos;
ctx.instance->flags |= BUFFER_FL_AGENT;
ctx.instance->msg_handle = msg_handle;
msg_handle->version = V3_PROTOCOL;
--
2.19.1
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