From b35fd5d5788184f685520352962f1a727ea91c1e Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Mon, 15 Apr 2013 16:20:50 +0200 Subject: [PATCH] device: use safe_list for device event, fixes some hang issues Signed-off-by: Felix Fietkau --- device.c | 81 ++++++++++++++++++++++++++++++---------------------------------- device.h | 7 +++--- vlan.c | 2 +- 3 files changed, 43 insertions(+), 47 deletions(-) diff --git a/device.c b/device.c index 9ef444e..1c0736f 100644 --- a/device.c +++ b/device.c @@ -180,36 +180,22 @@ static void __init dev_init(void) avl_init(&devices, avl_strcmp, true, NULL); } - -static void __device_broadcast_event(struct list_head *head, enum device_event ev) +static int device_broadcast_cb(void *ctx, struct safe_list *list) { - struct device_user *dep; - static uint8_t idx[__DEV_EVENT_MAX]; - bool found; - - idx[ev]++; - do { - found = false; - - list_for_each_entry(dep, head, list) { - if (!dep->cb) - continue; + struct device_user *dep = container_of(list, struct device_user, list); + int *ev = ctx; - if (dep->ev_idx[ev] == idx[ev]) - continue; - - dep->cb(dep, ev); - dep->ev_idx[ev] = idx[ev]; - found = true; - break; - } - } while (found); + if (dep->cb) + dep->cb(dep, *ev); + return 0; } void device_broadcast_event(struct device *dev, enum device_event ev) { - __device_broadcast_event(&dev->aliases, ev); - __device_broadcast_event(&dev->users, ev); + int dev_ev = ev; + + safe_list_for_each(&dev->aliases, device_broadcast_cb, &dev_ev); + safe_list_for_each(&dev->users, device_broadcast_cb, &dev_ev); } int device_claim(struct device_user *dep) @@ -276,8 +262,8 @@ void device_init_virtual(struct device *dev, const struct device_type *type, con strncpy(dev->ifname, name, IFNAMSIZ); D(DEVICE, "Initialize device '%s'\n", dev->ifname); - INIT_LIST_HEAD(&dev->users); - INIT_LIST_HEAD(&dev->aliases); + INIT_SAFE_LIST(&dev->users); + INIT_SAFE_LIST(&dev->aliases); dev->type = type; if (!dev->set_state) @@ -356,19 +342,21 @@ device_delete(struct device *dev) dev->avl.key = NULL; } -void device_cleanup(struct device *dev) +static int device_cleanup_cb(void *ctx, struct safe_list *list) { - struct device_user *dep, *tmp; - - D(DEVICE, "Clean up device '%s'\n", dev->ifname); - list_for_each_entry_safe(dep, tmp, &dev->users, list) { - if (!dep->cb) - continue; - + struct device_user *dep = container_of(list, struct device_user, list); + if (dep->cb) dep->cb(dep, DEV_EVENT_REMOVE); - device_release(dep); - } + device_release(dep); + return 0; +} + +void device_cleanup(struct device *dev) +{ + D(DEVICE, "Clean up device '%s'\n", dev->ifname); + safe_list_for_each(&dev->users, device_cleanup_cb, NULL); + safe_list_for_each(&dev->aliases, device_cleanup_cb, NULL); device_delete(dev); } @@ -407,7 +395,10 @@ static int device_refcount(struct device *dev) struct list_head *list; int count = 0; - list_for_each(list, &dev->users) + list_for_each(list, &dev->users.list) + count++; + + list_for_each(list, &dev->aliases.list) count++; return count; @@ -415,7 +406,7 @@ static int device_refcount(struct device *dev) void device_add_user(struct device_user *dep, struct device *dev) { - struct list_head *head; + struct safe_list *head; if (dep->dev) device_remove_user(dep); @@ -429,7 +420,8 @@ void device_add_user(struct device_user *dep, struct device *dev) head = &dev->aliases; else head = &dev->users; - list_add_tail(&dep->list, head); + + safe_list_add(&dep->list, head); D(DEVICE, "Add user for device '%s', refcount=%d\n", dev->ifname, device_refcount(dev)); if (dep->cb && dev->present) { @@ -452,7 +444,9 @@ device_free(struct device *dev) static void __device_free_unused(struct device *dev) { - if (!list_empty(&dev->users) || dev->current_config || __devlock) + if (!safe_list_empty(&dev->users) || + !safe_list_empty(&dev->aliases) || + dev->current_config || __devlock) return; device_free(dev); @@ -469,7 +463,7 @@ void device_remove_user(struct device_user *dep) if (dep->claimed) device_release(dep); - list_del(&dep->list); + safe_list_del(&dep->list); dep->dev = NULL; D(DEVICE, "Remove user for device '%s', refcount=%d\n", dev->ifname, device_refcount(dev)); __device_free_unused(dev); @@ -545,9 +539,10 @@ device_replace(struct device *dev, struct device *odev) if (present) device_set_present(odev, false); - list_for_each_entry_safe(dep, tmp, &odev->users, list) { + list_for_each_entry_safe(dep, tmp, &odev->users.list, list.list) { device_release(dep); - list_move_tail(&dep->list, &dev->users); + safe_list_del(&dep->list); + safe_list_add(&dep->list, &dev->users); dep->dev = dev; } device_free(odev); diff --git a/device.h b/device.h index 1f852ab..1068a46 100644 --- a/device.h +++ b/device.h @@ -15,6 +15,7 @@ #define __LL_H #include +#include #include struct device; @@ -83,7 +84,7 @@ enum device_event { * device dependency with callbacks */ struct device_user { - struct list_head list; + struct safe_list list; bool claimed; bool hotplug; @@ -110,8 +111,8 @@ struct device { const struct device_type *type; struct avl_node avl; - struct list_head users; - struct list_head aliases; + struct safe_list users; + struct safe_list aliases; char ifname[IFNAMSIZ + 1]; int ifindex; diff --git a/vlan.c b/vlan.c index ee0652f..4589675 100644 --- a/vlan.c +++ b/vlan.c @@ -99,7 +99,7 @@ static struct device *get_vlan_device(struct device *dev, int id, bool create) struct device_user *dep; /* look for an existing interface before creating a new one */ - list_for_each_entry(dep, &dev->users, list) { + list_for_each_entry(dep, &dev->users.list, list.list) { if (dep->cb != vlan_dev_cb) continue; -- 2.11.0