Directory lookups show up in profiling. The queue files are responsible
for a large proportion of file-related system calls in udev coldplug.
Instead of creating a file for each event, append their details to a
log file. The file is periodically rebuilt (garbage-collected) to
prevent it from growing indefinitely.
This single queue file replaces both the queue directory and the
uevent_seqnum file. On desktop systems the file tends not to grow
beyond one page. So it should also save a small amount of memory in
tmpfs.
Tests on a running EeePC indicate average savings of 5% *udevd* cpu time
as measured by oprofile. __link_path_walk is reduced from 1.5% to
1.3%. It is not completely clear where the rest of the gains come from.
In tests running ~400 events, the queue file is rebuilt about 5 times.
Signed-off-by: Alan Jenkins <alan-jenkins@xxxxxxxxxxxxxx>
---
udev/Makefile.am | 1 +
udev/lib/libudev-private.h | 12 +-
udev/lib/libudev-queue-export.c | 447 ++++++++++++++++++++++++++++++++++++++
udev/lib/libudev-queue-private.h | 51 +++++
udev/lib/libudev-queue.c | 311 ++++++++++++++++++--------
udev/lib/libudev.h | 2 +
udev/udevadm-settle.c | 22 +--
udev/udevd.c | 154 +------------
8 files changed, 744 insertions(+), 256 deletions(-)
create mode 100644 udev/lib/libudev-queue-export.c
create mode 100644 udev/lib/libudev-queue-private.h
diff --git a/udev/Makefile.am b/udev/Makefile.am
index fa8279d..6cd2f23 100644
--- a/udev/Makefile.am
+++ b/udev/Makefile.am
@@ -30,6 +30,7 @@ common_files = \
lib/libudev-monitor.c \
lib/libudev-enumerate.c \
lib/libudev-queue.c \
+ lib/libudev-queue-export.c \
lib/libudev-ctrl.c
if USE_SELINUX
diff --git a/udev/lib/libudev-private.h b/udev/lib/libudev-private.h
index 9ec5e1a..aa57b8b 100644
--- a/udev/lib/libudev-private.h
+++ b/udev/lib/libudev-private.h
@@ -149,11 +149,13 @@ void udev_list_entry_set_flag(struct udev_list_entry *list_entry, int flag);
entry != NULL; \
entry = tmp, tmp = udev_list_entry_get_next(tmp))
-/* libudev-queue */
-int udev_queue_export_udev_seqnum(struct udev_queue *udev_queue, unsigned long long int seqnum);
-int udev_queue_export_device_queued(struct udev_queue *udev_queue, struct udev_device *udev_device);
-int udev_queue_export_device_finished(struct udev_queue *udev_queue, struct udev_device *udev_device);
-int udev_queue_export_device_failed(struct udev_queue *udev_queue, struct udev_device *udev_device);
+/* libudev-queue-export */
+struct udev_queue_export *udev_queue_export_new(struct udev *udev);
+void udev_queue_export_unref(struct udev_queue_export *udev_queue_export);
+void udev_queue_export_cleanup(struct udev_queue_export *udev_queue_export);
+int udev_queue_export_device_queued(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device);
+int udev_queue_export_device_finished(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device);
+int udev_queue_export_device_failed(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device);
/* libudev-utils */
#define UTIL_PATH_SIZE 1024
diff --git a/udev/lib/libudev-queue-export.c b/udev/lib/libudev-queue-export.c
new file mode 100644
index 0000000..1b5610f
--- /dev/null
+++ b/udev/lib/libudev-queue-export.c
@@ -0,0 +1,447 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008 Kay Sievers <kay.sievers@xxxxxxxx>
+ * Copyright (C) 2009 Alan Jenkins <alan-jenkins@xxxxxxxxxxxxxx>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <limits.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <assert.h>
+
+#include "udev.h"
+#include "libudev-queue-private.h"
+
+static int rebuild_queue_file(struct udev_queue_export *udev_queue_export);
+
+struct udev_queue_export {
+ struct udev *udev;
+ int failed_count; /* number of failed events exported */
+ int queued_count; /* number of unfinished events exported in queue file */
+ FILE *queue_file;
+ unsigned long long int seqnum_max; /* earliest sequence number in queue file */
+ unsigned long long int seqnum_min; /* latest sequence number in queue file */
+ int waste_bytes; /* queue file bytes wasted on finished events */
+};
+
+struct udev_queue_export *udev_queue_export_new(struct udev *udev)
+{
+ struct udev_queue_export *udev_queue_export;
+ unsigned long long int initial_seqnum;
+
+ if (udev == NULL)
+ return NULL;
+
+ udev_queue_export = calloc(1, sizeof(struct udev_queue_export));
+ if (udev_queue_export == NULL)
+ return NULL;
+ udev_queue_export->udev = udev;
+
+ initial_seqnum = udev_get_kernel_seqnum(udev);
+ udev_queue_export->seqnum_min = initial_seqnum;
+ udev_queue_export->seqnum_max = initial_seqnum;
+
+ udev_queue_export_cleanup(udev_queue_export);
+ if (rebuild_queue_file(udev_queue_export) != 0) {
+ free(udev_queue_export);
+ return NULL;
+ }
+
+ return udev_queue_export;
+}
+
+void udev_queue_export_unref(struct udev_queue_export *udev_queue_export)
+{
+ if (udev_queue_export == NULL)
+ return;
+ if (udev_queue_export->queue_file != NULL)
+ fclose(udev_queue_export->queue_file);
+ free(udev_queue_export);
+}
+
+void udev_queue_export_cleanup(struct udev_queue_export *udev_queue_export)
+{
+ char filename[UTIL_PATH_SIZE];
+
+ util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_queue_export->udev), "/.udev/queue.tmp", NULL);
+ unlink(filename);
+
+ util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_queue_export->udev), "/.udev/queue.bin", NULL);
+ unlink(filename);
+}
+
+
+static int skip_to(FILE *file, long offset)
+{
+ long old_offset;
+
+ /* fseek may drop buffered data, avoid it for small seeks */
+ old_offset = ftell(file);
+ if (offset > old_offset && old_offset - offset <= BUFSIZ) {
+ size_t skip_bytes = old_offset - offset;
+ char buf[skip_bytes];
+
+ if (fread(buf, skip_bytes, 1, file) != skip_bytes)
+ return -1;
+ }
+
+ return fseek(file, offset, SEEK_SET);
+}
+
+struct queue_devpaths {
+ int devpaths_first; /* index of first queued event */
+ int devpaths_size;
+ long devpaths[]; /* seqnum -> offset of devpath in queue file (or 0) */
+};
+
+/*
+ * Returns a table mapping seqnum to devpath file offset for currently queued events.
+ * devpaths[i] represents the event with seqnum = i + udev_queue_export->seqnum_min.
+ */
+static struct queue_devpaths *build_index(struct udev_queue_export *udev_queue_export)
+{
+ struct queue_devpaths *devpaths;
+ unsigned long long int range;
+ long devpath_offset;
+ ssize_t devpath_len;
+ unsigned long long int seqnum;
+ unsigned long long int n;
+ int i;
+
+ /* seek to the first event in the file */
+ rewind(udev_queue_export->queue_file);
+ read_seqnum(udev_queue_export->queue_file, &seqnum);
+
+ /* allocate the table */
+ range = udev_queue_export->seqnum_min - udev_queue_export->seqnum_max;
+ if (range - 1 > INT_MAX) {
+ err(udev_queue_export->udev, "queue file overflow\n");
+ return NULL;
+ }
+ devpaths = calloc(1, sizeof(struct queue_devpaths) + (range + 1) * sizeof(long));
+ if (index == NULL)
+ return NULL;
+ devpaths->devpaths_size = range + 1;
+
+ /* read all records and populate the table */
+ while(1) {
+ if (read_seqnum(udev_queue_export->queue_file, &seqnum) < 0)
+ break;
+ n = seqnum - udev_queue_export->seqnum_max;
+ if (n >= devpaths->devpaths_size)
+ goto read_error;
+
+ devpath_offset = ftell(udev_queue_export->queue_file);
+ devpath_len = skip_devpath(udev_queue_export->queue_file);
+ if (devpath_len < 0)
+ goto read_error;
+
+ if (devpath_len > 0)
+ devpaths->devpaths[n] = devpath_offset;
+ else
+ devpaths->devpaths[n] = 0;
+ }
+
+ /* find first queued event */
+ for (i = 0; i < devpaths->devpaths_size; i++) {
+ if (devpaths->devpaths[i] != 0)
+ break;
+ }
+ devpaths->devpaths_first = i;
+
+ return devpaths;
+
+read_error:
+ err(udev_queue_export->udev, "queue file corrupted\n");
+ free(devpaths);
+ return NULL;
+}
+
+static int rebuild_queue_file(struct udev_queue_export *udev_queue_export)
+{
+ unsigned long long int seqnum;
+ struct queue_devpaths *devpaths = NULL;
+ char filename[UTIL_PATH_SIZE];
+ char filename_tmp[UTIL_PATH_SIZE];
+ FILE *new_queue_file = NULL;
+ int i;
+
+ /* read old queue file */
+ if (udev_queue_export->queue_file != NULL) {
+ dbg(udev_queue_export->udev, "compacting queue file, freeing %d bytes\n",
+ udev_queue_export->waste_bytes);
+
+ devpaths = build_index(udev_queue_export);
+ if (devpaths != NULL)
+ udev_queue_export->seqnum_max += devpaths->devpaths_first;
+ }
+ if (devpaths == NULL) {
+ dbg(udev_queue_export->udev, "creating empty queue file\n");
+ udev_queue_export->queued_count = 0;
+ udev_queue_export->seqnum_max = udev_queue_export->seqnum_min;
+ }
+
+ /* create new queue file */
+ util_strscpyl(filename_tmp, sizeof(filename_tmp), udev_get_dev_path(udev_queue_export->udev), "/.udev/queue.tmp", NULL);
+ new_queue_file = fopen(filename_tmp, "w+");
+ if (new_queue_file == NULL)
+ goto error;
+ seqnum = udev_queue_export->seqnum_max;
+ fwrite(&seqnum, 1, sizeof(unsigned long long int), new_queue_file);
+
+ /* copy unfinished events only to the new file */
+ if (devpaths != NULL) {
+ for (i = devpaths->devpaths_first; i < devpaths->devpaths_size; i++) {
+ char devpath[UTIL_PATH_SIZE];
+ int err;
+ unsigned short devpath_len;
+
+ if (devpaths->devpaths[i] != 0)
+ {
+ skip_to(udev_queue_export->queue_file, devpaths->devpaths[i]);
+ err = read_devpath(udev_queue_export->queue_file, devpath, sizeof(devpath));
+ devpath_len = err;
+
+ fwrite(&seqnum, sizeof(unsigned long long int), 1, new_queue_file);
+ fwrite(&devpath_len, sizeof(unsigned short), 1, new_queue_file);
+ fwrite(devpath, 1, devpath_len, new_queue_file);
+ }
+ seqnum++;
+ }
+ free(devpaths);
+ devpaths = NULL;
+ }
+ fflush(new_queue_file);
+ if (ferror(new_queue_file))
+ goto error;
+
+ /* rename the new file on top of the old one */
+ util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_queue_export->udev), "/.udev/queue.bin", NULL);
+ if (rename(filename_tmp, filename) != 0)
+ goto error;
+
+ if (udev_queue_export->queue_file != NULL)
+ fclose(udev_queue_export->queue_file);
+ udev_queue_export->queue_file = new_queue_file;
+ udev_queue_export->waste_bytes = 0;
+
+ return 0;
+
+error:
+ err(udev_queue_export->udev, "failed to create queue file: %m\n");
+ udev_queue_export_cleanup(udev_queue_export);
+
+ if (udev_queue_export->queue_file != NULL) {
+ fclose(udev_queue_export->queue_file);
+ udev_queue_export->queue_file = NULL;
+ }
+ if (new_queue_file != NULL)
+ fclose(new_queue_file);
+
+ if (devpaths != NULL)
+ free(devpaths);
+ udev_queue_export->queued_count = 0;
+ udev_queue_export->waste_bytes = 0;
+ udev_queue_export->seqnum_max = udev_queue_export->seqnum_min;
+
+ return -1;
+}
+
+static int write_queue_record(struct udev_queue_export *udev_queue_export,
+ unsigned long long int seqnum, const char *devpath, size_t devpath_len)
+{
+ unsigned short len;
+
+ if (udev_queue_export->queue_file == NULL) {
+ dbg(udev_queue_export->udev, "can't record event: queue file not available\n");
+ return -1;
+ }
+
+ if (fwrite(&seqnum, sizeof(unsigned long long int), 1, udev_queue_export->queue_file) != 1)
+ goto write_error;
+
+ len = (devpath_len < USHRT_MAX) ? devpath_len : USHRT_MAX;
+ if (fwrite(&len, sizeof(unsigned short), 1, udev_queue_export->queue_file) != 1)
+ goto write_error;
+ if (fwrite(devpath, 1, len, udev_queue_export->queue_file) != len)
+ goto write_error;
+
+ /* *must* flush output; caller may fork */
+ if (fflush(udev_queue_export->queue_file) != 0)
+ goto write_error;
+
+ return 0;
+
+write_error:
+ /* if we failed half way through writing a record to a file,
+ we should not try to write any further records to it. */
+ err(udev_queue_export->udev, "error writing to queue file: %m\n");
+ fclose(udev_queue_export->queue_file);
+ udev_queue_export->queue_file = NULL;
+
+ return -1;
+}
+
+
+enum device_state {
+ DEVICE_QUEUED,
+ DEVICE_FINISHED,
+ DEVICE_FAILED,
+};
+
+static inline size_t queue_record_size(size_t devpath_len)
+{
+ return sizeof(unsigned long long int) + sizeof(unsigned short int) + devpath_len;
+}
+
+static int update_queue(struct udev_queue_export *udev_queue_export,
+ struct udev_device *udev_device, enum device_state state)
+{
+ unsigned long long int seqnum = udev_device_get_seqnum(udev_device);
+ const char *devpath = NULL;
+ size_t devpath_len = 0;
+ int bytes;
+ int err;
+
+ if (state == DEVICE_QUEUED) {
+ devpath = udev_device_get_devpath(udev_device);
+ devpath_len = strlen(devpath);
+ }
+
+ /* recover from an earlier failed rebuild */
+ if (udev_queue_export->queue_file == NULL) {
+ if (rebuild_queue_file(udev_queue_export) != 0)
+ return -1;
+ }
+
+ /* when the queue files grow too large, they must be garbage collected and rebuilt */
+ bytes = ftell(udev_queue_export->queue_file) + queue_record_size(devpath_len);
+
+ /* if we're removing the last event from the queue, that's the best time to rebuild it */
+ if (state != DEVICE_QUEUED && udev_queue_export->queued_count == 1 && bytes > 2048) {
+ /* because we don't need to read the old queue file */
+ fclose(udev_queue_export->queue_file);
+ udev_queue_export->queue_file = NULL;
+ rebuild_queue_file(udev_queue_export);
+ return 0;
+ }
+
+ /* try to rebuild the queue files before they grow larger than one page. */
+ if ((udev_queue_export->waste_bytes > bytes / 2) && bytes > 4096)
+ rebuild_queue_file(udev_queue_export);
+
+ /* don't record a finished event, if we already dropped the event in a failed rebuild */
+ if (seqnum < udev_queue_export->seqnum_max)
+ return 0;
+
+ /* now write to the queue */
+ if (state == DEVICE_QUEUED) {
+ udev_queue_export->queued_count++;
+ udev_queue_export->seqnum_min = seqnum;
+ } else {
+ udev_queue_export->waste_bytes += queue_record_size(devpath_len) + queue_record_size(0);
+ udev_queue_export->queued_count--;
+ }
+ err = write_queue_record(udev_queue_export, seqnum, devpath, devpath_len);
+
+ /* try to handle ENOSPC */
+ if (err != 0 && udev_queue_export->queued_count == 0) {
+ udev_queue_export_cleanup(udev_queue_export);
+ err = rebuild_queue_file(udev_queue_export);
+ }
+
+ return err;
+}
+
+static void update_failed(struct udev_queue_export *udev_queue_export,
+ struct udev_device *udev_device, enum device_state state)
+{
+ struct udev *udev = udev_device_get_udev(udev_device);
+ char filename[UTIL_PATH_SIZE];
+ char *s;
+ size_t l;
+
+ if (state != DEVICE_FAILED && udev_queue_export->failed_count == 0)
+ return;
+
+ /* location of failed file */
+ s = filename;
+ l = util_strpcpyl(&s, sizeof(filename), udev_get_dev_path(udev_queue_export->udev), "/.udev/failed/", NULL);
+ util_path_encode(udev_device_get_devpath(udev_device), s, l);
+
+ switch (state) {
+ case DEVICE_FAILED:
+ /* record event in the failed directory */
+ if (udev_queue_export->failed_count == 0)
+ util_create_path(udev, filename);
+ udev_queue_export->failed_count++;
+
+ udev_selinux_setfscreatecon(udev, filename, S_IFLNK);
+ symlink(udev_device_get_devpath(udev_device), filename);
+ udev_selinux_resetfscreatecon(udev);
+ break;
+
+ case DEVICE_QUEUED:
+ /* delete failed file */
+ if (unlink(filename) == 0) {
+ util_delete_path(udev, filename);
+ udev_queue_export->failed_count--;
+ }
+ break;
+
+ case DEVICE_FINISHED:
+ if (udev_device_get_devpath_old(udev_device) != NULL) {
+ /* "move" event - rename failed file to current name, do not delete failed */
+ char filename_old[UTIL_PATH_SIZE];
+
+ s = filename_old;
+ l = util_strpcpyl(&s, sizeof(filename_old), udev_get_dev_path(udev_queue_export->udev), "/.udev/failed/", NULL);
+ util_path_encode(udev_device_get_devpath_old(udev_device), s, l);
+
+ if (rename(filename_old, filename) == 0)
+ info(udev, "renamed devpath, moved failed state of '%s' to %s'\n",
+ udev_device_get_devpath_old(udev_device), udev_device_get_devpath(udev_device));
+ }
+ break;
+ }
+
+ return;
+}
+
+static int update(struct udev_queue_export *udev_queue_export,
+ struct udev_device *udev_device, enum device_state state)
+{
+ update_failed(udev_queue_export, udev_device, state);
+
+ if (update_queue(udev_queue_export, udev_device, state) != 0)
+ return -1;
+
+ return 0;
+}
+
+int udev_queue_export_device_queued(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device)
+{
+ return update(udev_queue_export, udev_device, DEVICE_QUEUED);
+}
+
+int udev_queue_export_device_finished(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device)
+{
+ return update(udev_queue_export, udev_device, DEVICE_FINISHED);
+}
+
+int udev_queue_export_device_failed(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device)
+{
+ return update(udev_queue_export, udev_device, DEVICE_FAILED);
+}
diff --git a/udev/lib/libudev-queue-private.h b/udev/lib/libudev-queue-private.h
new file mode 100644
index 0000000..13c8b5f
--- /dev/null
+++ b/udev/lib/libudev-queue-private.h
@@ -0,0 +1,51 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008 Kay Sievers <kay.sievers@xxxxxxxx>
+ * Copyright (C) 2009 Alan Jenkins <alan-jenkins@xxxxxxxxxxxxxx>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ */
+
+#ifndef _LIBUDEV_QUEUE_PRIVATE_H_
+#define _LIBUDEV_PRIVATE_H_
+
+/*
+ * DISCLAIMER - The file format mentioned here is private to udev/libudev,
+ * and may be changed without notice.
+ *
+ *
+ * The udev event queue is exported as a binary log file.
+ * Each log record consists of a sequence number followed by the device path.
+ *
+ * When a new event is queued, its details are appended to the log.
+ * When the event finishes, a second record is appended to the log
+ * with the same sequence number but a null devpath.
+ *
+ * Example:
+ * {1, "/devices/virtual/mem/null" },
+ * {2, "/devices/virtual/mem/zero" },
+ * {1, "" },
+ * Event 2 is still queued, but event 1 has been finished
+ *
+ * The queue does not grow indefinitely. It is periodically re-created
+ * to remove finished events. Atomic rename() makes this transparent to readers.
+ *
+ *
+ * The queue file starts with a single sequence number which specifies the
+ * minimum sequence number in the log that follows. Any events prior to this
+ * sequence number have already finished.
+ */
+
+extern int read_seqnum(FILE *queue_file, unsigned long long int *seqnum);
+
+/* return value is the length of devpath */
+extern ssize_t read_devpath(FILE *queue_file, char *devpath, size_t size);
+extern ssize_t skip_devpath(FILE *queue_file);
+
+extern unsigned long long int udev_get_kernel_seqnum(struct udev *udev);
+
+#endif
diff --git a/udev/lib/libudev-queue.c b/udev/lib/libudev-queue.c
index 8dce6c3..b8c411c 100644
--- a/udev/lib/libudev-queue.c
+++ b/udev/lib/libudev-queue.c
@@ -2,6 +2,7 @@
* libudev - interface to udev device information
*
* Copyright (C) 2008 Kay Sievers <kay.sievers@xxxxxxxx>
+ * Copyright (C) 2009 Alan Jenkins <alan-jenkins@xxxxxxxxxxxxxx>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@@ -17,15 +18,16 @@
#include <string.h>
#include <dirent.h>
#include <fcntl.h>
+#include <limits.h>
#include <sys/stat.h>
#include "libudev.h"
#include "libudev-private.h"
+#include "libudev-queue-private.h"
struct udev_queue {
struct udev *udev;
int refcount;
- unsigned long long int last_seen_udev_seqnum;
struct udev_list_node queue_list;
struct udev_list_node failed_list;
};
@@ -74,7 +76,7 @@ struct udev *udev_queue_get_udev(struct udev_queue *udev_queue)
return udev_queue->udev;
}
-unsigned long long int udev_queue_get_kernel_seqnum(struct udev_queue *udev_queue)
+unsigned long long int udev_get_kernel_seqnum(struct udev *udev)
{
char filename[UTIL_PATH_SIZE];
unsigned long long int seqnum;
@@ -82,9 +84,7 @@ unsigned long long int udev_queue_get_kernel_seqnum(struct udev_queue *udev_queu
char buf[32];
ssize_t len;
- if (udev_queue == NULL)
- return -EINVAL;
- util_strscpyl(filename, sizeof(filename), udev_get_sys_path(udev_queue->udev), "/kernel/uevent_seqnum", NULL);
+ util_strscpyl(filename, sizeof(filename), udev_get_sys_path(udev), "/kernel/uevent_seqnum", NULL);
fd = open(filename, O_RDONLY);
if (fd < 0)
return 0;
@@ -94,130 +94,271 @@ unsigned long long int udev_queue_get_kernel_seqnum(struct udev_queue *udev_queu
return 0;
buf[len-1] = '\0';
seqnum = strtoull(buf, NULL, 10);
- dbg(udev_queue->udev, "seqnum=%llu\n", seqnum);
return seqnum;
}
-unsigned long long int udev_queue_get_udev_seqnum(struct udev_queue *udev_queue)
+unsigned long long int udev_queue_get_kernel_seqnum(struct udev_queue *udev_queue)
{
- char filename[UTIL_PATH_SIZE];
unsigned long long int seqnum;
- int fd;
- char buf[32];
- ssize_t len;
if (udev_queue == NULL)
return -EINVAL;
- util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_queue->udev), "/.udev/uevent_seqnum", NULL);
- fd = open(filename, O_RDONLY);
- if (fd < 0)
- return 0;
- len = read(fd, buf, sizeof(buf));
- close(fd);
- if (len <= 2)
- return 0;
- buf[len-1] = '\0';
- seqnum = strtoull(buf, NULL, 10);
+
+ seqnum = udev_get_kernel_seqnum(udev_queue->udev);
dbg(udev_queue->udev, "seqnum=%llu\n", seqnum);
- udev_queue->last_seen_udev_seqnum = seqnum;
return seqnum;
}
-int udev_queue_get_udev_is_active(struct udev_queue *udev_queue)
+int read_seqnum(FILE *queue_file, unsigned long long int *seqnum)
+{
+ if (fread(seqnum, sizeof(unsigned long long int), 1, queue_file) != 1)
+ return -1;
+
+ return 0;
+}
+
+ssize_t skip_devpath(FILE *queue_file)
+{
+ unsigned short int len;
+
+ if (fread(&len, sizeof(unsigned short int), 1, queue_file) == 1) {
+ char devpath[len];
+
+ /* use fread to skip, fseek might drop buffered data */
+ if (fread(devpath, 1, len, queue_file) == len)
+ return len;
+ }
+
+ return -1;
+}
+
+ssize_t read_devpath(FILE *queue_file, char *devpath, size_t size)
+{
+ unsigned short int read_bytes = 0;
+ unsigned short int len;
+
+ if (fread(&len, sizeof(unsigned short int), 1, queue_file) != 1)
+ return -1;
+
+ read_bytes = (len < size - 1) ? len : size - 1;
+ if (fread(devpath, 1, read_bytes, queue_file) != read_bytes)
+ return -1;
+ devpath[read_bytes] = '\0';
+
+ /* if devpath was too long, skip unread characters */
+ if (read_bytes != len) {
+ unsigned short int skip_bytes = len - read_bytes;
+ char buf[skip_bytes];
+
+ if (fread(buf, 1, skip_bytes, queue_file) != skip_bytes)
+ return -1;
+ }
+
+ return read_bytes;
+}
+
+static FILE *open_queue_file(struct udev_queue *udev_queue, unsigned long long int *seqnum_start)
{
char filename[UTIL_PATH_SIZE];
- struct stat statbuf;
+ FILE *queue_file;
- if (udev_queue == NULL)
+ util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_queue->udev), "/.udev/queue.bin", NULL);
+ queue_file = fopen(filename, "r");
+ if (queue_file == NULL)
+ return NULL;
+
+ if (read_seqnum(queue_file, seqnum_start) < 0) {
+ err(udev_queue->udev, "corrupt queue file\n");
+ fclose(queue_file);
+ return NULL;
+ }
+
+ return queue_file;
+}
+
+
+unsigned long long int udev_queue_get_udev_seqnum(struct udev_queue *udev_queue)
+{
+ unsigned long long int seqnum_udev;
+ FILE *queue_file;
+
+ queue_file = open_queue_file(udev_queue, &seqnum_udev);
+ if (queue_file == NULL)
return 0;
- util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_queue->udev), "/.udev/uevent_seqnum", NULL);
- if (stat(filename, &statbuf) == 0)
- return 1;
- return 0;
+
+ while (1) {
+ unsigned long long int seqnum;
+ ssize_t devpath_len;
+
+ if (read_seqnum(queue_file, &seqnum) < 0)
+ break;
+ devpath_len = skip_devpath(queue_file);
+ if (devpath_len < 0)
+ break;
+ if (devpath_len > 0)
+ seqnum_udev = seqnum;
+ }
+
+ fclose(queue_file);
+ return seqnum_udev;
+}
+
+int udev_queue_get_udev_is_active(struct udev_queue *udev_queue)
+{
+ unsigned long long int seqnum_start;
+ FILE *queue_file;
+
+ queue_file = open_queue_file(udev_queue, &seqnum_start);
+ if (queue_file == NULL)
+ return 0;
+
+ fclose(queue_file);
+ return 1;
}
int udev_queue_get_queue_is_empty(struct udev_queue *udev_queue)
{
- char queuename[UTIL_PATH_SIZE];
- struct stat statbuf;
unsigned long long int seqnum_kernel;
+ unsigned long long int seqnum_udev = 0;
+ int queued = 0;
+ int is_empty = 0;
+ FILE *queue_file;
if (udev_queue == NULL)
return -EINVAL;
- util_strscpyl(queuename, sizeof(queuename), udev_get_dev_path(udev_queue->udev), "/.udev/queue", NULL);
- if (stat(queuename, &statbuf) == 0) {
+ queue_file = open_queue_file(udev_queue, &seqnum_udev);
+ if (queue_file == NULL)
+ return 1;
+
+ while (1) {
+ unsigned long long int seqnum;
+ ssize_t devpath_len;
+
+ if (read_seqnum(queue_file, &seqnum) < 0)
+ break;
+ devpath_len = skip_devpath(queue_file);
+ if (devpath_len < 0)
+ break;
+
+ if (devpath_len > 0) {
+ queued++;
+ seqnum_udev = seqnum;
+ } else {
+ queued--;
+ }
+ }
+
+ if (queued > 0) {
dbg(udev_queue->udev, "queue is not empty\n");
- return 0;
+ goto out;
}
+
seqnum_kernel = udev_queue_get_kernel_seqnum(udev_queue);
- if (seqnum_kernel <= udev_queue->last_seen_udev_seqnum) {
- dbg(udev_queue->udev, "queue is empty\n");
- return 1;
- }
- /* update udev seqnum, and check if udev is still running */
- if (udev_queue_get_udev_seqnum(udev_queue) == 0)
- if (!udev_queue_get_udev_is_active(udev_queue))
- return 1;
- if (seqnum_kernel <= udev_queue->last_seen_udev_seqnum) {
- dbg(udev_queue->udev, "queue is empty\n");
- return 1;
+ if (seqnum_udev < seqnum_kernel) {
+ dbg(udev_queue->udev, "queue is empty but kernel events still pending [%llu]<->[%llu]\n",
+ seqnum_kernel, seqnum_udev);
+ goto out;
}
- dbg(udev_queue->udev, "queue is empty, but kernel events still pending [%llu]<->[%llu]\n",
- seqnum_kernel, udev_queue->last_seen_udev_seqnum);
- return 0;
+
+ dbg(udev_queue->udev, "queue is empty\n");
+ is_empty = 1;
+
+out:
+ fclose(queue_file);
+ return is_empty;
}
-int udev_queue_get_seqnum_is_finished(struct udev_queue *udev_queue, unsigned long long int seqnum)
+int udev_queue_get_seqnums_are_finished(struct udev_queue *udev_queue,
+ unsigned long long int start, unsigned long long int end)
{
- char filename[UTIL_PATH_SIZE];
- struct stat statbuf;
+ unsigned long long int seqnum = 0;
+ ssize_t devpath_len;
+ int unfinished;
+ FILE *queue_file;
if (udev_queue == NULL)
return -EINVAL;
- /* did it reach the queue? */
- if (seqnum > udev_queue->last_seen_udev_seqnum)
- if (seqnum > udev_queue_get_udev_seqnum(udev_queue))
- return 0;
- /* is it still in the queue? */
- snprintf(filename, sizeof(filename), "%s/.udev/queue/%llu",
- udev_get_dev_path(udev_queue->udev), seqnum);
- if (lstat(filename, &statbuf) == 0)
+ queue_file = open_queue_file(udev_queue, &seqnum);
+ if (queue_file == NULL)
+ return 1;
+ if (start < seqnum)
+ start = seqnum;
+ if (start > end)
+ return 1;
+ if (end - start > INT_MAX - 1)
+ return -EOVERFLOW;
+ unfinished = (end - start) + 1;
+
+ while (unfinished > 0) {
+ if (read_seqnum(queue_file, &seqnum) < 0)
+ break;
+ devpath_len = skip_devpath(queue_file);
+ if (devpath_len < 0)
+ break;
+
+ if (devpath_len == 0) {
+ if (seqnum >= start && seqnum <= end)
+ unfinished--;
+ }
+ }
+ fclose(queue_file);
+
+ return (unfinished == 0);
+}
+
+int udev_queue_get_seqnum_is_finished(struct udev_queue *udev_queue, unsigned long long int seqnum)
+{
+ if (!udev_queue_get_seqnums_are_finished(udev_queue, seqnum, seqnum))
return 0;
+
dbg(udev_queue->udev, "seqnum: %llu finished\n", seqnum);
return 1;
}
struct udev_list_entry *udev_queue_get_queued_list_entry(struct udev_queue *udev_queue)
{
- char path[UTIL_PATH_SIZE];
- DIR *dir;
- struct dirent *dent;
+ unsigned long long int seqnum;
+ FILE *queue_file;
if (udev_queue == NULL)
return NULL;
udev_list_cleanup_entries(udev_queue->udev, &udev_queue->queue_list);
- util_strscpyl(path, sizeof(path), udev_get_dev_path(udev_queue->udev), "/.udev/queue", NULL);
- dir = opendir(path);
- if (dir == NULL)
+
+ queue_file = open_queue_file(udev_queue, &seqnum);
+ if (queue_file == NULL)
return NULL;
- for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+
+ while (1) {
char syspath[UTIL_PATH_SIZE];
char *s;
size_t l;
ssize_t len;
+ char seqnum_str[32];
+ struct udev_list_entry *list_entry;
+
+ if (read_seqnum(queue_file, &seqnum) < 0)
+ break;
+ snprintf(seqnum_str, sizeof(seqnum_str), "%llu", seqnum);
- if (dent->d_name[0] == '.')
- continue;
s = syspath;
l = util_strpcpyl(&s, sizeof(syspath), udev_get_sys_path(udev_queue->udev), NULL);
- len = readlinkat(dirfd(dir), dent->d_name, s, l);
- if (len < 0 || (size_t)len >= l)
- continue;
- s[len] = '\0';
- dbg(udev_queue->udev, "found '%s' [%s]\n", syspath, dent->d_name);
- udev_list_entry_add(udev_queue->udev, &udev_queue->queue_list, syspath, dent->d_name, 0, 0);
+ len = read_devpath(queue_file, s, l);
+ if (len < 0)
+ break;
+
+ if (len > 0) {
+ udev_list_entry_add(udev_queue->udev, &udev_queue->queue_list, syspath, seqnum_str, 0, 0);
+ } else {
+ udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_queue->queue_list)) {
+ if (strcmp(seqnum_str, udev_list_entry_get_value(list_entry)) == 0) {
+ udev_list_entry_delete(list_entry);
+ break;
+ }
+ }
+ }
}
- closedir(dir);
+ fclose(queue_file);
+
return udev_list_get_entry(&udev_queue->queue_list);
}
@@ -259,23 +400,3 @@ struct udev_list_entry *udev_queue_get_failed_list_entry(struct udev_queue *udev
closedir(dir);
return udev_list_get_entry(&udev_queue->failed_list);
}
-
-int udev_queue_export_udev_seqnum(struct udev_queue *udev_queue, unsigned long long int seqnum)
-{
- return -1;
-}
-
-int udev_queue_export_device_queued(struct udev_queue *udev_queue, struct udev_device *udev_device)
-{
- return -1;
-}
-
-int udev_queue_export_device_finished(struct udev_queue *udev_queue, struct udev_device *udev_device)
-{
- return -1;
-}
-
-int udev_queue_export_device_failed(struct udev_queue *udev_queue, struct udev_device *udev_device)
-{
- return -1;
-}
diff --git a/udev/lib/libudev.h b/udev/lib/libudev.h
index 9346eb4..a68540f 100644
--- a/udev/lib/libudev.h
+++ b/udev/lib/libudev.h
@@ -115,6 +115,8 @@ unsigned long long int udev_queue_get_udev_seqnum(struct udev_queue *udev_queue)
int udev_queue_get_udev_is_active(struct udev_queue *udev_queue);
int udev_queue_get_queue_is_empty(struct udev_queue *udev_queue);
int udev_queue_get_seqnum_is_finished(struct udev_queue *udev_queue, unsigned long long int seqnum);
+int udev_queue_get_seqnums_are_finished(struct udev_queue *udev_queue,
+ unsigned long long int start, unsigned long long int end);
struct udev_list_entry *udev_queue_get_queued_list_entry(struct udev_queue *udev_queue);
struct udev_list_entry *udev_queue_get_failed_list_entry(struct udev_queue *udev_queue);
#endif
diff --git a/udev/udevadm-settle.c b/udev/udevadm-settle.c
index 52d9c0b..b416806 100644
--- a/udev/udevadm-settle.c
+++ b/udev/udevadm-settle.c
@@ -173,24 +173,16 @@ int udevadm_settle(struct udev *udev, int argc, char *argv[])
}
while (!is_timeout) {
- /* exit if queue is empty */
- if (udev_queue_get_queue_is_empty(udev_queue))
- break;
-
- /* if asked for, wait for a specific sequence of events */
if (start > 0) {
- unsigned long long seq;
- int finished;
-
- finished = 0;
- for (seq = start; seq <= end; seq++) {
- finished = udev_queue_get_seqnum_is_finished(udev_queue, seq);
- if (!finished)
- break;
- }
- if (finished)
+ /* if asked for, wait for a specific sequence of events */
+ if (udev_queue_get_seqnums_are_finished(udev_queue, start, end) == 1)
+ break;
+ } else {
+ /* exit if queue is empty */
+ if (udev_queue_get_queue_is_empty(udev_queue))
break;
}
+
usleep(1000 * 1000 / LOOP_PER_SECOND);
}
diff --git a/udev/udevd.c b/udev/udevd.c
index ebe3999..96aa747 100644
--- a/udev/udevd.c
+++ b/udev/udevd.c
@@ -65,6 +65,7 @@ static void reap_sigchilds(void);
static int debug_trace;
static struct udev_rules *rules;
+static struct udev_queue_export *udev_queue_export;
static struct udev_ctrl *udev_ctrl;
static struct udev_monitor *kernel_monitor;
static volatile sig_atomic_t sigchilds_waiting;
@@ -78,12 +79,6 @@ static int max_childs;
static int childs;
static struct udev_list_node event_list;
-enum event_state {
- EVENT_QUEUED,
- EVENT_FINISHED,
- EVENT_FAILED,
-};
-
static struct udev_event *node_to_event(struct udev_list_node *node)
{
char *event;
@@ -93,76 +88,15 @@ static struct udev_event *node_to_event(struct udev_list_node *node)
return (struct udev_event *)event;
}
-static void export_event_state(struct udev_event *event, enum event_state state)
-{
- char filename[UTIL_PATH_SIZE];
- char filename_failed[UTIL_PATH_SIZE];
- char *s;
- size_t l;
-
- /* location of queue file */
- snprintf(filename, sizeof(filename), "%s/.udev/queue/%llu",
- udev_get_dev_path(event->udev), udev_device_get_seqnum(event->dev));
-
- /* location of failed file */
- s = filename_failed;
- l = util_strpcpyl(&s, sizeof(filename_failed), udev_get_dev_path(event->udev), "/.udev/failed/", NULL);
- util_path_encode(udev_device_get_devpath(event->dev), s, l);
-
- switch (state) {
- case EVENT_QUEUED:
- if(unlink(filename_failed) == 0)
- util_delete_path(event->udev, filename_failed);
- util_create_path(event->udev, filename);
- udev_selinux_setfscreatecon(event->udev, filename, S_IFLNK);
- symlink(udev_device_get_devpath(event->dev), filename);
- udev_selinux_resetfscreatecon(event->udev);
- break;
- case EVENT_FINISHED:
- if (udev_device_get_devpath_old(event->dev) != NULL) {
- /* "move" event - rename failed file to current name, do not delete failed */
- char filename_failed_old[UTIL_PATH_SIZE];
-
- s = filename_failed_old;
- l = util_strpcpyl(&s, sizeof(filename_failed_old), udev_get_dev_path(event->udev), "/.udev/failed/", NULL);
- util_path_encode(udev_device_get_devpath_old(event->dev), s, l);
- if (rename(filename_failed_old, filename_failed) == 0)
- info(event->udev, "renamed devpath, moved failed state of '%s' to %s'\n",
- udev_device_get_devpath_old(event->dev), udev_device_get_devpath(event->dev));
- } else {
- if (unlink(filename_failed) == 0)
- util_delete_path(event->udev, filename_failed);
- }
-
- unlink(filename);
-
- /* clean up possibly empty queue directory */
- if (udev_list_is_empty(&event_list))
- util_delete_path(event->udev, filename);
- break;
- case EVENT_FAILED:
- /* move failed event to the failed directory */
- util_create_path(event->udev, filename_failed);
- rename(filename, filename_failed);
-
- /* clean up possibly empty queue directory */
- if (udev_list_is_empty(&event_list))
- util_delete_path(event->udev, filename);
- break;
- }
-
- return;
-}
-
static void event_queue_delete(struct udev_event *event)
{
udev_list_node_remove(&event->node);
/* mark as failed, if "add" event returns non-zero */
if (event->exitstatus && strcmp(udev_device_get_action(event->dev), "add") == 0)
- export_event_state(event, EVENT_FAILED);
+ udev_queue_export_device_failed(udev_queue_export, event->dev);
else
- export_event_state(event, EVENT_FINISHED);
+ udev_queue_export_device_finished(udev_queue_export, event->dev);
udev_device_unref(event->dev);
udev_event_unref(event);
@@ -201,6 +135,7 @@ static void event_fork(struct udev_event *event)
switch (pid) {
case 0:
/* child */
+ udev_queue_export_unref(udev_queue_export);
udev_ctrl_unref(udev_ctrl);
logging_close();
logging_init("udevd-event");
@@ -267,27 +202,12 @@ static void event_fork(struct udev_event *event)
static void event_queue_insert(struct udev_event *event)
{
- char filename[UTIL_PATH_SIZE];
- int fd;
-
event->queue_time = time(NULL);
- export_event_state(event, EVENT_QUEUED);
+ udev_queue_export_device_queued(udev_queue_export, event->dev);
info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(event->dev),
udev_device_get_action(event->dev), udev_device_get_subsystem(event->dev));
- util_strscpyl(filename, sizeof(filename), udev_get_dev_path(event->udev), "/.udev/uevent_seqnum", NULL);
- fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
- if (fd >= 0) {
- char str[32];
- int len;
-
- len = sprintf(str, "%llu\n", udev_device_get_seqnum(event->dev));
- write(fd, str, len);
- close(fd);
- }
-
-
udev_list_node_append(&event->node, &event_list);
run_exec_q = 1;
@@ -639,59 +559,6 @@ static void reap_sigchilds(void)
}
}
-static void cleanup_queue_dir(struct udev *udev)
-{
- char dirname[UTIL_PATH_SIZE];
- char filename[UTIL_PATH_SIZE];
- DIR *dir;
-
- util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/uevent_seqnum", NULL);
- unlink(filename);
-
- util_strscpyl(dirname, sizeof(dirname), udev_get_dev_path(udev), "/.udev/queue", NULL);
- dir = opendir(dirname);
- if (dir != NULL) {
- while (1) {
- struct dirent *dent;
-
- dent = readdir(dir);
- if (dent == NULL || dent->d_name[0] == '\0')
- break;
- if (dent->d_name[0] == '.')
- continue;
- unlinkat(dirfd(dir), dent->d_name, 0);
- }
- closedir(dir);
- rmdir(dirname);
- }
-}
-
-static void export_initial_seqnum(struct udev *udev)
-{
- char filename[UTIL_PATH_SIZE];
- int fd;
- char seqnum[32];
- ssize_t len = 0;
-
- util_strscpyl(filename, sizeof(filename), udev_get_sys_path(udev), "/kernel/uevent_seqnum", NULL);
- fd = open(filename, O_RDONLY);
- if (fd >= 0) {
- len = read(fd, seqnum, sizeof(seqnum)-1);
- close(fd);
- }
- if (len <= 0) {
- strcpy(seqnum, "0\n");
- len = 3;
- }
- util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/uevent_seqnum", NULL);
- util_create_path(udev, filename);
- fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
- if (fd >= 0) {
- write(fd, seqnum, len);
- close(fd);
- }
-}
-
static void startup_log(struct udev *udev)
{
FILE *f;
@@ -839,8 +706,11 @@ int main(int argc, char *argv[])
goto exit;
}
udev_list_init(&event_list);
- cleanup_queue_dir(udev);
- export_initial_seqnum(udev);
+ udev_queue_export = udev_queue_export_new(udev);
+ if (udev_queue_export == NULL) {
+ err(udev, "error creating queue file\n");
+ goto exit;
+ }
if (daemonize) {
pid_t pid;
@@ -1029,9 +899,11 @@ handle_signals:
settle_pid = 0;
}
}
- cleanup_queue_dir(udev);
+ udev_queue_export_cleanup(udev_queue_export);
rc = 0;
exit:
+
+ udev_queue_export_unref(udev_queue_export);
udev_rules_unref(rules);
udev_ctrl_unref(udev_ctrl);
if (inotify_fd >= 0)
--
1.6.0.4
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