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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /tools/virtio/virtio-trace/trace-agent.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'tools/virtio/virtio-trace/trace-agent.c')
-rw-r--r--tools/virtio/virtio-trace/trace-agent.c272
1 files changed, 272 insertions, 0 deletions
diff --git a/tools/virtio/virtio-trace/trace-agent.c b/tools/virtio/virtio-trace/trace-agent.c
new file mode 100644
index 000000000..7e2d9bbf0
--- /dev/null
+++ b/tools/virtio/virtio-trace/trace-agent.c
@@ -0,0 +1,272 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Guest agent for virtio-trace
+ *
+ * Copyright (C) 2012 Hitachi, Ltd.
+ * Created by Yoshihiro Yunomae <yoshihiro.yunomae.ez@hitachi.com>
+ * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
+ */
+
+#define _GNU_SOURCE
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include "trace-agent.h"
+
+#define PAGE_SIZE (sysconf(_SC_PAGE_SIZE))
+#define PIPE_DEF_BUFS 16
+#define PIPE_MIN_SIZE (PAGE_SIZE*PIPE_DEF_BUFS)
+#define PIPE_MAX_SIZE (1024*1024)
+#define TRACEFS "/sys/kernel/tracing"
+#define DEBUGFS "/sys/kernel/debug/tracing"
+#define READ_PATH_FMT "%s/per_cpu/cpu%d/trace_pipe_raw"
+#define WRITE_PATH_FMT "/dev/virtio-ports/trace-path-cpu%d"
+#define CTL_PATH "/dev/virtio-ports/agent-ctl-path"
+
+pthread_mutex_t mutex_notify = PTHREAD_MUTEX_INITIALIZER;
+pthread_cond_t cond_wakeup = PTHREAD_COND_INITIALIZER;
+
+static int get_total_cpus(void)
+{
+ int nr_cpus = (int)sysconf(_SC_NPROCESSORS_CONF);
+
+ if (nr_cpus <= 0) {
+ pr_err("Could not read cpus\n");
+ goto error;
+ } else if (nr_cpus > MAX_CPUS) {
+ pr_err("Exceed max cpus(%d)\n", (int)MAX_CPUS);
+ goto error;
+ }
+
+ return nr_cpus;
+
+error:
+ exit(EXIT_FAILURE);
+}
+
+static void *agent_info_new(void)
+{
+ struct agent_info *s;
+ int i;
+
+ s = zalloc(sizeof(struct agent_info));
+ if (s == NULL) {
+ pr_err("agent_info zalloc error\n");
+ exit(EXIT_FAILURE);
+ }
+
+ s->pipe_size = PIPE_INIT;
+ s->use_stdout = false;
+ s->cpus = get_total_cpus();
+ s->ctl_fd = -1;
+
+ /* read/write threads init */
+ for (i = 0; i < s->cpus; i++)
+ s->rw_ti[i] = rw_thread_info_new();
+
+ return s;
+}
+
+static unsigned long parse_size(const char *arg)
+{
+ unsigned long value, round;
+ char *ptr;
+
+ value = strtoul(arg, &ptr, 10);
+ switch (*ptr) {
+ case 'K': case 'k':
+ value <<= 10;
+ break;
+ case 'M': case 'm':
+ value <<= 20;
+ break;
+ default:
+ break;
+ }
+
+ if (value > PIPE_MAX_SIZE) {
+ pr_err("Pipe size must be less than 1MB\n");
+ goto error;
+ } else if (value < PIPE_MIN_SIZE) {
+ pr_err("Pipe size must be over 64KB\n");
+ goto error;
+ }
+
+ /* Align buffer size with page unit */
+ round = value & (PAGE_SIZE - 1);
+ value = value - round;
+
+ return value;
+error:
+ return 0;
+}
+
+static void usage(char const *prg)
+{
+ pr_err("usage: %s [-h] [-o] [-s <size of pipe>]\n", prg);
+}
+
+static const char *make_path(int cpu_num, bool this_is_write_path)
+{
+ int ret;
+ char *buf;
+
+ buf = zalloc(PATH_MAX);
+ if (buf == NULL) {
+ pr_err("Could not allocate buffer\n");
+ goto error;
+ }
+
+ if (this_is_write_path)
+ /* write(output) path */
+ ret = snprintf(buf, PATH_MAX, WRITE_PATH_FMT, cpu_num);
+ else {
+ /* read(input) path */
+ ret = snprintf(buf, PATH_MAX, READ_PATH_FMT, TRACEFS, cpu_num);
+ if (ret > 0 && access(buf, F_OK) != 0)
+ ret = snprintf(buf, PATH_MAX, READ_PATH_FMT, DEBUGFS, cpu_num);
+ }
+
+ if (ret <= 0) {
+ pr_err("Failed to generate %s path(CPU#%d):%d\n",
+ this_is_write_path ? "read" : "write", cpu_num, ret);
+ goto error;
+ }
+
+ return buf;
+
+error:
+ free(buf);
+ return NULL;
+}
+
+static const char *make_input_path(int cpu_num)
+{
+ return make_path(cpu_num, false);
+}
+
+static const char *make_output_path(int cpu_num)
+{
+ return make_path(cpu_num, true);
+}
+
+static void *agent_info_init(struct agent_info *s)
+{
+ int cpu;
+ const char *in_path = NULL;
+ const char *out_path = NULL;
+
+ /* init read/write threads */
+ for (cpu = 0; cpu < s->cpus; cpu++) {
+ /* set read(input) path per read/write thread */
+ in_path = make_input_path(cpu);
+ if (in_path == NULL)
+ goto error;
+
+ /* set write(output) path per read/write thread*/
+ if (!s->use_stdout) {
+ out_path = make_output_path(cpu);
+ if (out_path == NULL)
+ goto error;
+ } else
+ /* stdout mode */
+ pr_debug("stdout mode\n");
+
+ rw_thread_init(cpu, in_path, out_path, s->use_stdout,
+ s->pipe_size, s->rw_ti[cpu]);
+ }
+
+ /* init controller of read/write threads */
+ s->ctl_fd = rw_ctl_init((const char *)CTL_PATH);
+
+ return NULL;
+
+error:
+ exit(EXIT_FAILURE);
+}
+
+static void *parse_args(int argc, char *argv[], struct agent_info *s)
+{
+ int cmd;
+ unsigned long size;
+
+ while ((cmd = getopt(argc, argv, "hos:")) != -1) {
+ switch (cmd) {
+ /* stdout mode */
+ case 'o':
+ s->use_stdout = true;
+ break;
+ /* size of pipe */
+ case 's':
+ size = parse_size(optarg);
+ if (size == 0)
+ goto error;
+ s->pipe_size = size;
+ break;
+ case 'h':
+ default:
+ usage(argv[0]);
+ goto error;
+ }
+ }
+
+ agent_info_init(s);
+
+ return NULL;
+
+error:
+ exit(EXIT_FAILURE);
+}
+
+static void agent_main_loop(struct agent_info *s)
+{
+ int cpu;
+ pthread_t rw_thread_per_cpu[MAX_CPUS];
+
+ /* Start all read/write threads */
+ for (cpu = 0; cpu < s->cpus; cpu++)
+ rw_thread_per_cpu[cpu] = rw_thread_run(s->rw_ti[cpu]);
+
+ rw_ctl_loop(s->ctl_fd);
+
+ /* Finish all read/write threads */
+ for (cpu = 0; cpu < s->cpus; cpu++) {
+ int ret;
+
+ ret = pthread_join(rw_thread_per_cpu[cpu], NULL);
+ if (ret != 0) {
+ pr_err("pthread_join() error:%d (cpu %d)\n", ret, cpu);
+ exit(EXIT_FAILURE);
+ }
+ }
+}
+
+static void agent_info_free(struct agent_info *s)
+{
+ int i;
+
+ close(s->ctl_fd);
+ for (i = 0; i < s->cpus; i++) {
+ close(s->rw_ti[i]->in_fd);
+ close(s->rw_ti[i]->out_fd);
+ close(s->rw_ti[i]->read_pipe);
+ close(s->rw_ti[i]->write_pipe);
+ free(s->rw_ti[i]);
+ }
+ free(s);
+}
+
+int main(int argc, char *argv[])
+{
+ struct agent_info *s = NULL;
+
+ s = agent_info_new();
+ parse_args(argc, argv, s);
+
+ agent_main_loop(s);
+
+ agent_info_free(s);
+
+ return 0;
+}