-/*
+/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
+ *
+ * lttng-statedump.c
+ *
* Linux Trace Toolkit Next Generation Kernel State Dump
*
* Copyright 2005 Jean-Hugues Deschenes <jean-hugues.deschenes@polymtl.ca>
* Eric Clement: Add listing of network IP interface
* 2006, 2007 Mathieu Desnoyers Fix kernel threads
* Various updates
- *
- * Dual LGPL v2.1/GPL v2 license.
*/
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/netdevice.h>
#include <linux/inetdevice.h>
-#include <linux/sched.h>
#include <linux/mm.h>
-#include <linux/fdtable.h>
#include <linux/swap.h>
#include <linux/wait.h>
#include <linux/mutex.h>
-
-#include "lttng-events.h"
-#include "wrapper/irqdesc.h"
-
-#ifdef CONFIG_GENERIC_HARDIRQS
+#include <linux/device.h>
+
+#include <lttng-events.h>
+#include <lttng-tracer.h>
+#include <wrapper/irqdesc.h>
+#include <wrapper/spinlock.h>
+#include <wrapper/fdtable.h>
+#include <wrapper/irq.h>
+#include <wrapper/tracepoint.h>
+#include <wrapper/genhd.h>
+#include <wrapper/file.h>
+#include <wrapper/fdtable.h>
+#include <wrapper/sched.h>
+
+#ifdef CONFIG_LTTNG_HAS_LIST_IRQ
#include <linux/irq.h>
#endif
/* Define the tracepoints, but do not build the probes */
#define CREATE_TRACE_POINTS
-#define TRACE_INCLUDE_PATH ../instrumentation/events/lttng-module
+#define TRACE_INCLUDE_PATH instrumentation/events/lttng-module
#define TRACE_INCLUDE_FILE lttng-statedump
-#include "instrumentation/events/lttng-module/lttng-statedump.h"
+#define LTTNG_INSTRUMENTATION
+#include <instrumentation/events/lttng-module/lttng-statedump.h>
+
+LTTNG_DEFINE_TRACE(lttng_statedump_block_device,
+ TP_PROTO(struct lttng_session *session,
+ dev_t dev, const char *diskname),
+ TP_ARGS(session, dev, diskname));
+
+LTTNG_DEFINE_TRACE(lttng_statedump_end,
+ TP_PROTO(struct lttng_session *session),
+ TP_ARGS(session));
+
+LTTNG_DEFINE_TRACE(lttng_statedump_interrupt,
+ TP_PROTO(struct lttng_session *session,
+ unsigned int irq, const char *chip_name,
+ struct irqaction *action),
+ TP_ARGS(session, irq, chip_name, action));
+
+LTTNG_DEFINE_TRACE(lttng_statedump_file_descriptor,
+ TP_PROTO(struct lttng_session *session,
+ struct task_struct *p, int fd, const char *filename,
+ unsigned int flags, fmode_t fmode),
+ TP_ARGS(session, p, fd, filename, flags, fmode));
+
+LTTNG_DEFINE_TRACE(lttng_statedump_start,
+ TP_PROTO(struct lttng_session *session),
+ TP_ARGS(session));
+
+LTTNG_DEFINE_TRACE(lttng_statedump_process_state,
+ TP_PROTO(struct lttng_session *session,
+ struct task_struct *p,
+ int type, int mode, int submode, int status,
+ struct pid_namespace *pid_ns),
+ TP_ARGS(session, p, type, mode, submode, status, pid_ns));
+
+LTTNG_DEFINE_TRACE(lttng_statedump_network_interface,
+ TP_PROTO(struct lttng_session *session,
+ struct net_device *dev, struct in_ifaddr *ifa),
+ TP_ARGS(session, dev, ifa));
+
+struct lttng_fd_ctx {
+ char *page;
+ struct lttng_session *session;
+ struct task_struct *p;
+ struct files_struct *files;
+};
/*
* Protected by the trace lock.
LTTNG_DEAD = 7,
};
+
+#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,11,0))
+
+#define LTTNG_PART_STRUCT_TYPE struct block_device
+
+static
+int lttng_get_part_name(struct gendisk *disk, struct block_device *part, char *name_buf)
+{
+ const char *p;
+
+ p = bdevname(part, name_buf);
+ if (!p)
+ return -ENOSYS;
+
+ return 0;
+}
+
+static
+dev_t lttng_get_part_devt(struct block_device *part)
+{
+ return part->bd_dev;
+}
+
+#else
+
+#define LTTNG_PART_STRUCT_TYPE struct hd_struct
+
+static
+int lttng_get_part_name(struct gendisk *disk, struct hd_struct *part, char *name_buf)
+{
+ const char *p;
+ struct block_device bdev;
+
+ /*
+ * Create a partial 'struct blockdevice' to use
+ * 'bdevname()' which is a simple wrapper over
+ * 'disk_name()' but has the honor to be EXPORT_SYMBOL.
+ */
+ bdev.bd_disk = disk;
+ bdev.bd_part = part;
+
+ p = bdevname(&bdev, name_buf);
+ if (!p)
+ return -ENOSYS;
+
+ return 0;
+}
+
+static
+dev_t lttng_get_part_devt(struct hd_struct *part)
+{
+ return part_devt(part);
+}
+#endif
+
+#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,12,0))
+static
+int lttng_statedump_each_block_device(struct lttng_session *session, struct gendisk *disk)
+{
+ struct block_device *part;
+ unsigned long idx;
+ int ret = 0;
+
+ /* Include partition 0 */
+ idx = 0;
+
+ rcu_read_lock();
+ xa_for_each(&disk->part_tbl, idx, part) {
+ char name_buf[BDEVNAME_SIZE];
+
+ /* Exclude non-partitions bdev and empty partitions. */
+ if (bdev_is_partition(part) && !bdev_nr_sectors(part))
+ continue;
+
+ if (lttng_get_part_name(disk, part, name_buf) == -ENOSYS) {
+ ret = -ENOSYS;
+ goto end;
+ }
+ trace_lttng_statedump_block_device(session, lttng_get_part_devt(part),
+ name_buf);
+ }
+end:
+ rcu_read_unlock();
+ return ret;
+}
+#else
+static
+int lttng_statedump_each_block_device(struct lttng_session *session, struct gendisk *disk)
+{
+ struct disk_part_iter piter;
+ LTTNG_PART_STRUCT_TYPE *part;
+
+ disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
+
+ while ((part = disk_part_iter_next(&piter))) {
+ char name_buf[BDEVNAME_SIZE];
+
+ if (lttng_get_part_name(disk, part, name_buf) == -ENOSYS) {
+ disk_part_iter_exit(&piter);
+ return -ENOSYS;
+ }
+ trace_lttng_statedump_block_device(session, lttng_get_part_devt(part),
+ name_buf);
+ }
+ disk_part_iter_exit(&piter);
+
+ return 0;
+}
+#endif
+
+static
+int lttng_enumerate_block_devices(struct lttng_session *session)
+{
+ struct class *ptr_block_class;
+ struct device_type *ptr_disk_type;
+ struct class_dev_iter iter;
+ struct device *dev;
+ int ret = 0;
+
+ ptr_block_class = wrapper_get_block_class();
+ if (!ptr_block_class) {
+ ret = -ENOSYS;
+ goto end;
+ }
+ ptr_disk_type = wrapper_get_disk_type();
+ if (!ptr_disk_type) {
+ ret = -ENOSYS;
+ goto end;
+ }
+ class_dev_iter_init(&iter, ptr_block_class, NULL, ptr_disk_type);
+ while ((dev = class_dev_iter_next(&iter))) {
+ struct gendisk *disk = dev_to_disk(dev);
+
+ /*
+ * Don't show empty devices or things that have been
+ * suppressed
+ */
+ if (get_capacity(disk) == 0 ||
+ (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
+ continue;
+
+ ret = lttng_statedump_each_block_device(session, disk);
+ }
+ class_dev_iter_exit(&iter);
+end:
+ return ret;
+}
+
#ifdef CONFIG_INET
+
static
void lttng_enumerate_device(struct lttng_session *session,
struct net_device *dev)
}
#endif /* CONFIG_INET */
+static
+int lttng_dump_one_fd(const void *p, struct file *file, unsigned int fd)
+{
+ const struct lttng_fd_ctx *ctx = p;
+ const char *s = d_path(&file->f_path, ctx->page, PAGE_SIZE);
+ unsigned int flags = file->f_flags;
+ struct fdtable *fdt;
+
+ /*
+ * We don't expose kernel internal flags, only userspace-visible
+ * flags.
+ */
+ flags &= ~FMODE_NONOTIFY;
+ fdt = files_fdtable(ctx->files);
+ /*
+ * We need to check here again whether fd is within the fdt
+ * max_fds range, because we might be seeing a different
+ * files_fdtable() than iterate_fd(), assuming only RCU is
+ * protecting the read. In reality, iterate_fd() holds
+ * file_lock, which should ensure the fdt does not change while
+ * the lock is taken, but we are not aware whether this is
+ * guaranteed or not, so play safe.
+ */
+ if (fd < fdt->max_fds && lttng_close_on_exec(fd, fdt))
+ flags |= O_CLOEXEC;
+ if (IS_ERR(s)) {
+ struct dentry *dentry = file->f_path.dentry;
+
+ /* Make sure we give at least some info */
+ spin_lock(&dentry->d_lock);
+ trace_lttng_statedump_file_descriptor(ctx->session, ctx->p, fd,
+ dentry->d_name.name, flags, file->f_mode);
+ spin_unlock(&dentry->d_lock);
+ goto end;
+ }
+ trace_lttng_statedump_file_descriptor(ctx->session, ctx->p, fd, s,
+ flags, file->f_mode);
+end:
+ return 0;
+}
static
void lttng_enumerate_task_fd(struct lttng_session *session,
struct task_struct *p, char *tmp)
{
- struct fdtable *fdt;
- struct file *filp;
- unsigned int i;
- const unsigned char *path;
+ struct lttng_fd_ctx ctx = { .page = tmp, .session = session, .p = p };
+ struct files_struct *files;
task_lock(p);
- if (!p->files)
- goto unlock_task;
- spin_lock(&p->files->file_lock);
- fdt = files_fdtable(p->files);
- for (i = 0; i < fdt->max_fds; i++) {
- filp = fcheck_files(p->files, i);
- if (!filp)
- continue;
- path = d_path(&filp->f_path, tmp, PAGE_SIZE);
- /* Make sure we give at least some info */
- trace_lttng_statedump_file_descriptor(session, p, i,
- IS_ERR(path) ?
- filp->f_dentry->d_name.name :
- path);
- }
- spin_unlock(&p->files->file_lock);
-unlock_task:
+ files = p->files;
+ if (!files)
+ goto end;
+ ctx.files = files;
+ lttng_iterate_fd(files, 0, lttng_dump_one_fd, &ctx);
+end:
task_unlock(p);
}
int lttng_enumerate_file_descriptors(struct lttng_session *session)
{
struct task_struct *p;
- char *tmp = (char *) __get_free_page(GFP_KERNEL);
+ char *tmp;
+
+ tmp = (char *) __get_free_page(GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
/* Enumerate active file descriptors */
rcu_read_lock();
return 0;
}
+#if 0
+/*
+ * FIXME: we cannot take a mmap_sem while in a RCU read-side critical section
+ * (scheduling in atomic). Normally, the tasklist lock protects this kind of
+ * iteration, but it is not exported to modules.
+ */
static
void lttng_enumerate_task_vm_maps(struct lttng_session *session,
struct task_struct *p)
down_read(&mm->mmap_sem);
while (map) {
if (map->vm_file)
- ino = map->vm_file->f_dentry->d_inode->i_ino;
+ ino = map->vm_file->lttng_f_dentry->d_inode->i_ino;
else
ino = 0;
trace_lttng_statedump_vm_map(session, p, map, ino);
rcu_read_unlock();
return 0;
}
+#endif
+
+#ifdef CONFIG_LTTNG_HAS_LIST_IRQ
+
+#if (LTTNG_LINUX_VERSION_CODE < LTTNG_KERNEL_VERSION(2,6,39))
+#define irq_desc_get_chip(desc) get_irq_desc_chip(desc)
+#endif
-#ifdef CONFIG_GENERIC_HARDIRQS
static
-void lttng_list_interrupts(struct lttng_session *session)
+int lttng_list_interrupts(struct lttng_session *session)
{
unsigned int irq;
unsigned long flags = 0;
irq_desc_get_chip(desc)->name ? : "unnamed_irq_chip";
local_irq_save(flags);
- raw_spin_lock(&desc->lock);
+ wrapper_desc_spin_lock(&desc->lock);
for (action = desc->action; action; action = action->next) {
trace_lttng_statedump_interrupt(session,
irq, irq_chip_name, action);
}
- raw_spin_unlock(&desc->lock);
+ wrapper_desc_spin_unlock(&desc->lock);
local_irq_restore(flags);
}
+ return 0;
#undef irq_to_desc
}
#else
static inline
-void list_interrupts(struct lttng_session *session)
+int lttng_list_interrupts(struct lttng_session *session)
{
+ return 0;
}
#endif
+/*
+ * Called with task lock held.
+ */
+static
+void lttng_statedump_process_ns(struct lttng_session *session,
+ struct task_struct *p,
+ enum lttng_thread_type type,
+ enum lttng_execution_mode mode,
+ enum lttng_execution_submode submode,
+ enum lttng_process_status status)
+{
+ struct pid_namespace *pid_ns;
+
+ pid_ns = task_active_pid_ns(p);
+ do {
+ trace_lttng_statedump_process_state(session,
+ p, type, mode, submode, status, pid_ns);
+ pid_ns = pid_ns ? pid_ns->parent : NULL;
+ } while (pid_ns);
+}
+
static
int lttng_enumerate_process_states(struct lttng_session *session)
{
status = LTTNG_ZOMBIE;
else if (p->exit_state == EXIT_DEAD)
status = LTTNG_DEAD;
- else if (p->state == TASK_RUNNING) {
+ else if (lttng_task_is_running(p)) {
/* Is this a forked child that has not run yet? */
if (list_empty(&p->rt.run_list))
status = LTTNG_WAIT_FORK;
* was really running at this time.
*/
status = LTTNG_WAIT_CPU;
- } else if (p->state &
+ } else if (lttng_get_task_state(p) &
(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)) {
/* Task is waiting for something to complete */
status = LTTNG_WAIT;
type = LTTNG_USER_THREAD;
else
type = LTTNG_KERNEL_THREAD;
- trace_lttng_statedump_process_state(session,
+ lttng_statedump_process_ns(session,
p, type, mode, submode, status);
task_unlock(p);
} while_each_thread(g, p);
static
int do_lttng_statedump(struct lttng_session *session)
{
- int cpu;
+ int cpu, ret;
- printk(KERN_DEBUG "LTT state dump thread start\n");
trace_lttng_statedump_start(session);
- lttng_enumerate_process_states(session);
- lttng_enumerate_file_descriptors(session);
- lttng_enumerate_vm_maps(session);
- lttng_list_interrupts(session);
- lttng_enumerate_network_ip_interface(session);
+ ret = lttng_enumerate_process_states(session);
+ if (ret)
+ return ret;
+ ret = lttng_enumerate_file_descriptors(session);
+ if (ret)
+ return ret;
+ /*
+ * FIXME
+ * ret = lttng_enumerate_vm_maps(session);
+ * if (ret)
+ * return ret;
+ */
+ ret = lttng_list_interrupts(session);
+ if (ret)
+ return ret;
+ ret = lttng_enumerate_network_ip_interface(session);
+ if (ret)
+ return ret;
+ ret = lttng_enumerate_block_devices(session);
+ switch (ret) {
+ case 0:
+ break;
+ case -ENOSYS:
+ printk(KERN_WARNING "LTTng: block device enumeration is not supported by kernel\n");
+ break;
+ default:
+ return ret;
+ }
/* TODO lttng_dump_idt_table(session); */
/* TODO lttng_dump_softirq_vec(session); */
schedule_delayed_work_on(cpu, &cpu_work[cpu], 0);
}
/* Wait for all threads to run */
- __wait_event(statedump_wq, (atomic_read(&kernel_threads_to_run) != 0));
+ __wait_event(statedump_wq, (atomic_read(&kernel_threads_to_run) == 0));
put_online_cpus();
/* Our work is done */
- printk(KERN_DEBUG "LTT state dump end\n");
trace_lttng_statedump_end(session);
return 0;
}
*/
int lttng_statedump_start(struct lttng_session *session)
{
- printk(KERN_DEBUG "LTTng: state dump begin\n");
return do_lttng_statedump(session);
}
EXPORT_SYMBOL_GPL(lttng_statedump_start);
+static
+int __init lttng_statedump_init(void)
+{
+ /*
+ * Allow module to load even if the fixup cannot be done. This
+ * will allow seemless transition when the underlying issue fix
+ * is merged into the Linux kernel, and when tracepoint.c
+ * "tracepoint_module_notify" is turned into a static function.
+ */
+ (void) wrapper_lttng_fixup_sig(THIS_MODULE);
+ return 0;
+}
+
+module_init(lttng_statedump_init);
+
+static
+void __exit lttng_statedump_exit(void)
+{
+}
+
+module_exit(lttng_statedump_exit);
+
MODULE_LICENSE("GPL and additional rights");
MODULE_AUTHOR("Jean-Hugues Deschenes");
-MODULE_DESCRIPTION("Linux Trace Toolkit Next Generation Statedump");
+MODULE_DESCRIPTION("LTTng statedump provider");
+MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
+ __stringify(LTTNG_MODULES_MINOR_VERSION) "."
+ __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
+ LTTNG_MODULES_EXTRAVERSION);
projects / lttng-modules.git / blobdiff