From: Doug Thompson Date: Thu, 26 Jul 2007 17:41:15 +0000 (-0700) Subject: drivers/edac: fix edac_pci sysfs X-Git-Tag: v2.6.23-rc2~204 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d4c1465b7de9686c4c5aa533b15c09ab014aab3a;p=linux-2.6 drivers/edac: fix edac_pci sysfs This patch fixes sysfs exit code for the EDAC PCI device in a similiar manner and the previous fixes for EDAC_MC and EDAC_DEVICE. It removes the old (and incorrect) completion model and uses reference counts on per instance kobjects and on the edac core module. This pattern was applied to the edac_mc and edac_device code, but the EDAC PCI code was missed. In addition, this fixes a system hang after a low level driver was unloaded. (A cleanup function was called twice, which really screwed things up) Cc: Greg KH Cc: Alan Cox Signed-off-by: Doug Thompson Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/edac/edac_module.h b/drivers/edac/edac_module.h index 3664ae9ccd..cbc419c8eb 100644 --- a/drivers/edac/edac_module.h +++ b/drivers/edac/edac_module.h @@ -66,6 +66,10 @@ extern int edac_sysfs_pci_setup(void); extern void edac_sysfs_pci_teardown(void); extern int edac_pci_get_check_errors(void); extern int edac_pci_get_poll_msec(void); +extern void edac_pci_remove_sysfs(struct edac_pci_ctl_info *pci); +extern void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg); +extern void edac_pci_handle_npe(struct edac_pci_ctl_info *pci, + const char *msg); #else /* CONFIG_PCI */ /* pre-process these away */ #define edac_pci_do_parity_check() @@ -74,6 +78,8 @@ extern int edac_pci_get_poll_msec(void); #define edac_sysfs_pci_teardown() #define edac_pci_get_check_errors() #define edac_pci_get_poll_msec() +#define edac_pci_handle_pe() +#define edac_pci_handle_npe() #endif /* CONFIG_PCI */ #endif /* __EDAC_MODULE_H__ */ diff --git a/drivers/edac/edac_pci.c b/drivers/edac/edac_pci.c index d9cd5e048c..5dee9f5041 100644 --- a/drivers/edac/edac_pci.c +++ b/drivers/edac/edac_pci.c @@ -31,20 +31,12 @@ static DEFINE_MUTEX(edac_pci_ctls_mutex); static struct list_head edac_pci_list = LIST_HEAD_INIT(edac_pci_list); -static inline void edac_lock_pci_list(void) -{ - mutex_lock(&edac_pci_ctls_mutex); -} - -static inline void edac_unlock_pci_list(void) -{ - mutex_unlock(&edac_pci_ctls_mutex); -} - /* - * The alloc() and free() functions for the 'edac_pci' control info - * structure. The chip driver will allocate one of these for each - * edac_pci it is going to control/register with the EDAC CORE. + * edac_pci_alloc_ctl_info + * + * The alloc() function for the 'edac_pci' control info + * structure. The chip driver will allocate one of these for each + * edac_pci it is going to control/register with the EDAC CORE. */ struct edac_pci_ctl_info *edac_pci_alloc_ctl_info(unsigned int sz_pvt, const char *edac_pci_name) @@ -53,47 +45,59 @@ struct edac_pci_ctl_info *edac_pci_alloc_ctl_info(unsigned int sz_pvt, void *pvt; unsigned int size; + debugf1("%s()\n", __func__); + pci = (struct edac_pci_ctl_info *)0; pvt = edac_align_ptr(&pci[1], sz_pvt); size = ((unsigned long)pvt) + sz_pvt; - if ((pci = kzalloc(size, GFP_KERNEL)) == NULL) + /* Alloc the needed control struct memory */ + pci = kzalloc(size, GFP_KERNEL); + if (pci == NULL) return NULL; + /* Now much private space */ pvt = sz_pvt ? ((char *)pci) + ((unsigned long)pvt) : NULL; pci->pvt_info = pvt; - pci->op_state = OP_ALLOC; snprintf(pci->name, strlen(edac_pci_name) + 1, "%s", edac_pci_name); return pci; } - EXPORT_SYMBOL_GPL(edac_pci_alloc_ctl_info); /* * edac_pci_free_ctl_info() - * frees the memory allocated by edac_pci_alloc_ctl_info() function + * + * Last action on the pci control structure. + * + * call the remove sysfs informaton, which will unregister + * this control struct's kobj. When that kobj's ref count + * goes to zero, its release function will be call and then + * kfree() the memory. */ void edac_pci_free_ctl_info(struct edac_pci_ctl_info *pci) { - kfree(pci); -} + debugf1("%s()\n", __func__); + edac_pci_remove_sysfs(pci); +} EXPORT_SYMBOL_GPL(edac_pci_free_ctl_info); /* * find_edac_pci_by_dev() * scans the edac_pci list for a specific 'struct device *' + * + * return NULL if not found, or return control struct pointer */ static struct edac_pci_ctl_info *find_edac_pci_by_dev(struct device *dev) { struct edac_pci_ctl_info *pci; struct list_head *item; - debugf3("%s()\n", __func__); + debugf1("%s()\n", __func__); list_for_each(item, &edac_pci_list) { pci = list_entry(item, struct edac_pci_ctl_info, link); @@ -118,10 +122,13 @@ static int add_edac_pci_to_global_list(struct edac_pci_ctl_info *pci) struct list_head *item, *insert_before; struct edac_pci_ctl_info *rover; + debugf1("%s()\n", __func__); + insert_before = &edac_pci_list; /* Determine if already on the list */ - if (unlikely((rover = find_edac_pci_by_dev(pci->dev)) != NULL)) + rover = find_edac_pci_by_dev(pci->dev); + if (unlikely(rover != NULL)) goto fail0; /* Insert in ascending order by 'pci_idx', so find position */ @@ -157,6 +164,8 @@ fail1: /* * complete_edac_pci_list_del + * + * RCU completion callback to indicate item is deleted */ static void complete_edac_pci_list_del(struct rcu_head *head) { @@ -169,6 +178,8 @@ static void complete_edac_pci_list_del(struct rcu_head *head) /* * del_edac_pci_from_global_list + * + * remove the PCI control struct from the global list */ static void del_edac_pci_from_global_list(struct edac_pci_ctl_info *pci) { @@ -207,35 +218,52 @@ struct edac_pci_ctl_info *edac_pci_find(int idx) return NULL; } - EXPORT_SYMBOL_GPL(edac_pci_find); /* * edac_pci_workq_function() - * performs the operation scheduled by a workq request + * + * periodic function that performs the operation + * scheduled by a workq request, for a given PCI control struct */ static void edac_pci_workq_function(struct work_struct *work_req) { struct delayed_work *d_work = (struct delayed_work *)work_req; struct edac_pci_ctl_info *pci = to_edac_pci_ctl_work(d_work); + int msec; + unsigned long delay; - edac_lock_pci_list(); + debugf3("%s() checking\n", __func__); - if ((pci->op_state == OP_RUNNING_POLL) && - (pci->edac_check != NULL) && (edac_pci_get_check_errors())) - pci->edac_check(pci); + mutex_lock(&edac_pci_ctls_mutex); - edac_unlock_pci_list(); + if (pci->op_state == OP_RUNNING_POLL) { + /* we might be in POLL mode, but there may NOT be a poll func + */ + if ((pci->edac_check != NULL) && edac_pci_get_check_errors()) + pci->edac_check(pci); + + /* if we are on a one second period, then use round */ + msec = edac_pci_get_poll_msec(); + if (msec == 1000) + delay = round_jiffies(msecs_to_jiffies(msec)); + else + delay = msecs_to_jiffies(msec); + + /* Reschedule only if we are in POLL mode */ + queue_delayed_work(edac_workqueue, &pci->work, delay); + } - /* Reschedule */ - queue_delayed_work(edac_workqueue, &pci->work, - msecs_to_jiffies(edac_pci_get_poll_msec())); + mutex_unlock(&edac_pci_ctls_mutex); } /* * edac_pci_workq_setup() * initialize a workq item for this edac_pci instance * passing in the new delay period in msec + * + * locking model: + * called when 'edac_pci_ctls_mutex' is locked */ static void edac_pci_workq_setup(struct edac_pci_ctl_info *pci, unsigned int msec) @@ -255,6 +283,8 @@ static void edac_pci_workq_teardown(struct edac_pci_ctl_info *pci) { int status; + debugf0("%s()\n", __func__); + status = cancel_delayed_work(&pci->work); if (status == 0) flush_workqueue(edac_workqueue); @@ -262,19 +292,25 @@ static void edac_pci_workq_teardown(struct edac_pci_ctl_info *pci) /* * edac_pci_reset_delay_period + * + * called with a new period value for the workq period + * a) stop current workq timer + * b) restart workq timer with new value */ void edac_pci_reset_delay_period(struct edac_pci_ctl_info *pci, unsigned long value) { - edac_lock_pci_list(); + debugf0("%s()\n", __func__); edac_pci_workq_teardown(pci); + /* need to lock for the setup */ + mutex_lock(&edac_pci_ctls_mutex); + edac_pci_workq_setup(pci, value); - edac_unlock_pci_list(); + mutex_unlock(&edac_pci_ctls_mutex); } - EXPORT_SYMBOL_GPL(edac_pci_reset_delay_period); /* @@ -294,14 +330,13 @@ int edac_pci_add_device(struct edac_pci_ctl_info *pci, int edac_idx) debugf0("%s()\n", __func__); pci->pci_idx = edac_idx; + pci->start_time = jiffies; - edac_lock_pci_list(); + mutex_lock(&edac_pci_ctls_mutex); if (add_edac_pci_to_global_list(pci)) goto fail0; - pci->start_time = jiffies; - if (edac_pci_create_sysfs(pci)) { edac_pci_printk(pci, KERN_WARNING, "failed to create sysfs pci\n"); @@ -323,16 +358,16 @@ int edac_pci_add_device(struct edac_pci_ctl_info *pci, int edac_idx) pci->ctl_name, dev_name(pci), edac_op_state_to_string(pci->op_state)); - edac_unlock_pci_list(); + mutex_unlock(&edac_pci_ctls_mutex); return 0; + /* error unwind stack */ fail1: del_edac_pci_from_global_list(pci); fail0: - edac_unlock_pci_list(); + mutex_unlock(&edac_pci_ctls_mutex); return 1; } - EXPORT_SYMBOL_GPL(edac_pci_add_device); /* @@ -354,22 +389,25 @@ struct edac_pci_ctl_info *edac_pci_del_device(struct device *dev) debugf0("%s()\n", __func__); - edac_lock_pci_list(); + mutex_lock(&edac_pci_ctls_mutex); - if ((pci = find_edac_pci_by_dev(dev)) == NULL) { - edac_unlock_pci_list(); + /* ensure the control struct is on the global list + * if not, then leave + */ + pci = find_edac_pci_by_dev(dev); + if (pci == NULL) { + mutex_unlock(&edac_pci_ctls_mutex); return NULL; } pci->op_state = OP_OFFLINE; - edac_pci_workq_teardown(pci); - - edac_pci_remove_sysfs(pci); - del_edac_pci_from_global_list(pci); - edac_unlock_pci_list(); + mutex_unlock(&edac_pci_ctls_mutex); + + /* stop the workq timer */ + edac_pci_workq_teardown(pci); edac_printk(KERN_INFO, EDAC_PCI, "Removed device %d for %s %s: DEV %s\n", @@ -377,14 +415,20 @@ struct edac_pci_ctl_info *edac_pci_del_device(struct device *dev) return pci; } - EXPORT_SYMBOL_GPL(edac_pci_del_device); +/* + * edac_pci_generic_check + * + * a Generic parity check API + */ void edac_pci_generic_check(struct edac_pci_ctl_info *pci) { + debugf4("%s()\n", __func__); edac_pci_do_parity_check(); } +/* free running instance index counter */ static int edac_pci_idx; #define EDAC_PCI_GENCTL_NAME "EDAC PCI controller" @@ -392,6 +436,17 @@ struct edac_pci_gen_data { int edac_idx; }; +/* + * edac_pci_create_generic_ctl + * + * A generic constructor for a PCI parity polling device + * Some systems have more than one domain of PCI busses. + * For systems with one domain, then this API will + * provide for a generic poller. + * + * This routine calls the edac_pci_alloc_ctl_info() for + * the generic device, with default values + */ struct edac_pci_ctl_info *edac_pci_create_generic_ctl(struct device *dev, const char *mod_name) { @@ -421,13 +476,18 @@ struct edac_pci_ctl_info *edac_pci_create_generic_ctl(struct device *dev, return pci; } - EXPORT_SYMBOL_GPL(edac_pci_create_generic_ctl); +/* + * edac_pci_release_generic_ctl + * + * The release function of a generic EDAC PCI polling device + */ void edac_pci_release_generic_ctl(struct edac_pci_ctl_info *pci) { + debugf0("%s() pci mod=%s\n", __func__, pci->mod_name); + edac_pci_del_device(pci->dev); edac_pci_free_ctl_info(pci); } - EXPORT_SYMBOL_GPL(edac_pci_release_generic_ctl); diff --git a/drivers/edac/edac_pci_sysfs.c b/drivers/edac/edac_pci_sysfs.c index fac94cae2c..69f5dddabd 100644 --- a/drivers/edac/edac_pci_sysfs.c +++ b/drivers/edac/edac_pci_sysfs.c @@ -13,22 +13,25 @@ #include "edac_core.h" #include "edac_module.h" +/* Turn off this whole feature if PCI is not configured */ #ifdef CONFIG_PCI #define EDAC_PCI_SYMLINK "device" -static int check_pci_errors; /* default YES check PCI parity */ -static int edac_pci_panic_on_pe; /* default no panic on PCI Parity */ -static int edac_pci_log_pe = 1; /* log PCI parity errors */ +/* data variables exported via sysfs */ +static int check_pci_errors; /* default NO check PCI parity */ +static int edac_pci_panic_on_pe; /* default NO panic on PCI Parity */ +static int edac_pci_log_pe = 1; /* log PCI parity errors */ static int edac_pci_log_npe = 1; /* log PCI non-parity error errors */ +static int edac_pci_poll_msec = 1000; /* one second workq period */ + static atomic_t pci_parity_count = ATOMIC_INIT(0); static atomic_t pci_nonparity_count = ATOMIC_INIT(0); -static int edac_pci_poll_msec = 1000; -static struct kobject edac_pci_kobj; /* /sys/devices/system/edac/pci */ -static struct completion edac_pci_kobj_complete; +static struct kobject edac_pci_top_main_kobj; static atomic_t edac_pci_sysfs_refcount = ATOMIC_INIT(0); +/* getter functions for the data variables */ int edac_pci_get_check_errors(void) { return check_pci_errors; @@ -74,17 +77,22 @@ static void edac_pci_instance_release(struct kobject *kobj) { struct edac_pci_ctl_info *pci; - debugf1("%s()\n", __func__); + debugf0("%s()\n", __func__); + /* Form pointer to containing struct, the pci control struct */ pci = to_instance(kobj); - complete(&pci->kobj_complete); + + /* decrement reference count on top main kobj */ + kobject_put(&edac_pci_top_main_kobj); + + kfree(pci); /* Free the control struct */ } /* instance specific attribute structure */ struct instance_attribute { struct attribute attr; - ssize_t(*show) (struct edac_pci_ctl_info *, char *); - ssize_t(*store) (struct edac_pci_ctl_info *, const char *, size_t); + ssize_t(*show) (struct edac_pci_ctl_info *, char *); + ssize_t(*store) (struct edac_pci_ctl_info *, const char *, size_t); }; /* Function to 'show' fields from the edac_pci 'instance' structure */ @@ -112,6 +120,7 @@ static ssize_t edac_pci_instance_store(struct kobject *kobj, return -EIO; } +/* fs_ops table */ static struct sysfs_ops pci_instance_ops = { .show = edac_pci_instance_show, .store = edac_pci_instance_store @@ -134,48 +143,82 @@ static struct instance_attribute *pci_instance_attr[] = { NULL }; -/* the ktype for pci instance */ +/* the ktype for a pci instance */ static struct kobj_type ktype_pci_instance = { .release = edac_pci_instance_release, .sysfs_ops = &pci_instance_ops, .default_attrs = (struct attribute **)pci_instance_attr, }; +/* + * edac_pci_create_instance_kobj + * + * construct one EDAC PCI instance's kobject for use + */ static int edac_pci_create_instance_kobj(struct edac_pci_ctl_info *pci, int idx) { + struct kobject *main_kobj; int err; - pci->kobj.parent = &edac_pci_kobj; + debugf0("%s()\n", __func__); + + /* Set the parent and the instance's ktype */ + pci->kobj.parent = &edac_pci_top_main_kobj; pci->kobj.ktype = &ktype_pci_instance; err = kobject_set_name(&pci->kobj, "pci%d", idx); if (err) return err; + /* First bump the ref count on the top main kobj, which will + * track the number of PCI instances we have, and thus nest + * properly on keeping the module loaded + */ + main_kobj = kobject_get(&edac_pci_top_main_kobj); + if (!main_kobj) { + err = -ENODEV; + goto error_out; + } + + /* And now register this new kobject under the main kobj */ err = kobject_register(&pci->kobj); if (err != 0) { debugf2("%s() failed to register instance pci%d\n", __func__, idx); - return err; + kobject_put(&edac_pci_top_main_kobj); + goto error_out; } debugf1("%s() Register instance 'pci%d' kobject\n", __func__, idx); return 0; + + /* Error unwind statck */ +error_out: + return err; } -static void -edac_pci_delete_instance_kobj(struct edac_pci_ctl_info *pci, int idx) +/* + * edac_pci_unregister_sysfs_instance_kobj + * + * unregister the kobj for the EDAC PCI instance + */ +void edac_pci_unregister_sysfs_instance_kobj(struct edac_pci_ctl_info *pci) { - init_completion(&pci->kobj_complete); + debugf0("%s()\n", __func__); + + /* Unregister the instance kobject and allow its release + * function release the main reference count and then + * kfree the memory + */ kobject_unregister(&pci->kobj); - wait_for_completion(&pci->kobj_complete); } /***************************** EDAC PCI sysfs root **********************/ #define to_edacpci(k) container_of(k, struct edac_pci_ctl_info, kobj) #define to_edacpci_attr(a) container_of(a, struct edac_pci_attr, attr) +/* simple show/store functions for attributes */ static ssize_t edac_pci_int_show(void *ptr, char *buffer) { int *value = ptr; @@ -267,118 +310,189 @@ static struct edac_pci_dev_attribute *edac_pci_attr[] = { NULL, }; -/* No memory to release */ -static void edac_pci_release(struct kobject *kobj) +/* + * edac_pci_release_main_kobj + * + * This release function is called when the reference count to the + * passed kobj goes to zero. + * + * This kobj is the 'main' kobject that EDAC PCI instances + * link to, and thus provide for proper nesting counts + */ +static void edac_pci_release_main_kobj(struct kobject *kobj) { - struct edac_pci_ctl_info *pci; - pci = to_edacpci(kobj); + debugf0("%s() here to module_put(THIS_MODULE)\n", __func__); - debugf1("%s()\n", __func__); - complete(&pci->kobj_complete); + /* last reference to top EDAC PCI kobject has been removed, + * NOW release our ref count on the core module + */ + module_put(THIS_MODULE); } -static struct kobj_type ktype_edac_pci = { - .release = edac_pci_release, +/* ktype struct for the EDAC PCI main kobj */ +static struct kobj_type ktype_edac_pci_main_kobj = { + .release = edac_pci_release_main_kobj, .sysfs_ops = &edac_pci_sysfs_ops, .default_attrs = (struct attribute **)edac_pci_attr, }; /** - * edac_sysfs_pci_setup() + * edac_pci_main_kobj_setup() * * setup the sysfs for EDAC PCI attributes * assumes edac_class has already been initialized */ -int edac_pci_register_main_kobj(void) +int edac_pci_main_kobj_setup(void) { int err; struct sysdev_class *edac_class; - debugf1("%s()\n", __func__); + debugf0("%s()\n", __func__); + + /* check and count if we have already created the main kobject */ + if (atomic_inc_return(&edac_pci_sysfs_refcount) != 1) + return 0; + /* First time, so create the main kobject and its + * controls and atributes + */ edac_class = edac_get_edac_class(); if (edac_class == NULL) { debugf1("%s() no edac_class\n", __func__); - return -ENODEV; + err = -ENODEV; + goto decrement_count_fail; } - edac_pci_kobj.ktype = &ktype_edac_pci; + /* Need the kobject hook ups, and name setting */ + edac_pci_top_main_kobj.ktype = &ktype_edac_pci_main_kobj; + edac_pci_top_main_kobj.parent = &edac_class->kset.kobj; - edac_pci_kobj.parent = &edac_class->kset.kobj; - - err = kobject_set_name(&edac_pci_kobj, "pci"); + err = kobject_set_name(&edac_pci_top_main_kobj, "pci"); if (err) - return err; + goto decrement_count_fail; + + /* Bump the reference count on this module to ensure the + * modules isn't unloaded until we deconstruct the top + * level main kobj for EDAC PCI + */ + if (!try_module_get(THIS_MODULE)) { + debugf1("%s() try_module_get() failed\n", __func__); + err = -ENODEV; + goto decrement_count_fail; + } /* Instanstiate the pci object */ /* FIXME: maybe new sysdev_create_subdir() */ - err = kobject_register(&edac_pci_kobj); - + err = kobject_register(&edac_pci_top_main_kobj); if (err) { debugf1("Failed to register '.../edac/pci'\n"); - return err; + goto kobject_register_fail; } + /* At this point, to 'release' the top level kobject + * for EDAC PCI, then edac_pci_main_kobj_teardown() + * must be used, for resources to be cleaned up properly + */ debugf1("Registered '.../edac/pci' kobject\n"); return 0; + + /* Error unwind statck */ +kobject_register_fail: + module_put(THIS_MODULE); + +decrement_count_fail: + /* if are on this error exit, nothing to tear down */ + atomic_dec(&edac_pci_sysfs_refcount); + + return err; } /* - * edac_pci_unregister_main_kobj() + * edac_pci_main_kobj_teardown() * - * perform the sysfs teardown for the PCI attributes + * if no longer linked (needed) remove the top level EDAC PCI + * kobject with its controls and attributes */ -void edac_pci_unregister_main_kobj(void) +static void edac_pci_main_kobj_teardown(void) { debugf0("%s()\n", __func__); - init_completion(&edac_pci_kobj_complete); - kobject_unregister(&edac_pci_kobj); - wait_for_completion(&edac_pci_kobj_complete); + + /* Decrement the count and only if no more controller instances + * are connected perform the unregisteration of the top level + * main kobj + */ + if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) { + debugf0("%s() called kobject_unregister on main kobj\n", + __func__); + kobject_unregister(&edac_pci_top_main_kobj); + } } +/* + * + * edac_pci_create_sysfs + * + * Create the controls/attributes for the specified EDAC PCI device + */ int edac_pci_create_sysfs(struct edac_pci_ctl_info *pci) { int err; struct kobject *edac_kobj = &pci->kobj; - if (atomic_inc_return(&edac_pci_sysfs_refcount) == 1) { - err = edac_pci_register_main_kobj(); - if (err) { - atomic_dec(&edac_pci_sysfs_refcount); - return err; - } - } + debugf0("%s() idx=%d\n", __func__, pci->pci_idx); - err = edac_pci_create_instance_kobj(pci, pci->pci_idx); - if (err) { - if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) - edac_pci_unregister_main_kobj(); - } + /* create the top main EDAC PCI kobject, IF needed */ + err = edac_pci_main_kobj_setup(); + if (err) + return err; - debugf0("%s() idx=%d\n", __func__, pci->pci_idx); + /* Create this instance's kobject under the MAIN kobject */ + err = edac_pci_create_instance_kobj(pci, pci->pci_idx); + if (err) + goto unregister_cleanup; err = sysfs_create_link(edac_kobj, &pci->dev->kobj, EDAC_PCI_SYMLINK); if (err) { debugf0("%s() sysfs_create_link() returned err= %d\n", __func__, err); - return err; + goto symlink_fail; } return 0; + + /* Error unwind stack */ +symlink_fail: + edac_pci_unregister_sysfs_instance_kobj(pci); + +unregister_cleanup: + edac_pci_main_kobj_teardown(); + + return err; } +/* + * edac_pci_remove_sysfs + * + * remove the controls and attributes for this EDAC PCI device + */ void edac_pci_remove_sysfs(struct edac_pci_ctl_info *pci) { - debugf0("%s()\n", __func__); - - edac_pci_delete_instance_kobj(pci, pci->pci_idx); + debugf0("%s() index=%d\n", __func__, pci->pci_idx); + /* Remove the symlink */ sysfs_remove_link(&pci->kobj, EDAC_PCI_SYMLINK); - if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) - edac_pci_unregister_main_kobj(); + /* remove this PCI instance's sysfs entries */ + edac_pci_unregister_sysfs_instance_kobj(pci); + + /* Call the main unregister function, which will determine + * if this 'pci' is the last instance. + * If it is, the main kobject will be unregistered as a result + */ + debugf0("%s() calling edac_pci_main_kobj_teardown()\n", __func__); + edac_pci_main_kobj_teardown(); } /************************ PCI error handling *************************/ @@ -414,13 +528,14 @@ static u16 get_pci_parity_status(struct pci_dev *dev, int secondary) return status; } -typedef void (*pci_parity_check_fn_t) (struct pci_dev * dev); /* Clear any PCI parity errors logged by this device. */ static void edac_pci_dev_parity_clear(struct pci_dev *dev) { u8 header_type; + debugf0("%s()\n", __func__); + get_pci_parity_status(dev, 0); /* read the device TYPE, looking for bridges */ @@ -433,17 +548,28 @@ static void edac_pci_dev_parity_clear(struct pci_dev *dev) /* * PCI Parity polling * + * Fucntion to retrieve the current parity status + * and decode it + * */ static void edac_pci_dev_parity_test(struct pci_dev *dev) { + unsigned long flags; u16 status; u8 header_type; - /* read the STATUS register on this device - */ + /* stop any interrupts until we can acquire the status */ + local_irq_save(flags); + + /* read the STATUS register on this device */ status = get_pci_parity_status(dev, 0); - debugf2("PCI STATUS= 0x%04x %s\n", status, dev->dev.bus_id); + /* read the device TYPE, looking for bridges */ + pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type); + + local_irq_restore(flags); + + debugf4("PCI STATUS= 0x%04x %s\n", status, dev->dev.bus_id); /* check the status reg for errors */ if (status) { @@ -471,16 +597,14 @@ static void edac_pci_dev_parity_test(struct pci_dev *dev) } } - /* read the device TYPE, looking for bridges */ - pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type); - debugf2("PCI HEADER TYPE= 0x%02x %s\n", header_type, dev->dev.bus_id); + debugf4("PCI HEADER TYPE= 0x%02x %s\n", header_type, dev->dev.bus_id); if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE) { /* On bridges, need to examine secondary status register */ status = get_pci_parity_status(dev, 1); - debugf2("PCI SEC_STATUS= 0x%04x %s\n", status, dev->dev.bus_id); + debugf4("PCI SEC_STATUS= 0x%04x %s\n", status, dev->dev.bus_id); /* check the secondary status reg for errors */ if (status) { @@ -510,9 +634,12 @@ static void edac_pci_dev_parity_test(struct pci_dev *dev) } } +/* reduce some complexity in definition of the iterator */ +typedef void (*pci_parity_check_fn_t) (struct pci_dev *dev); + /* * pci_dev parity list iterator - * Scan the PCI device list for one iteration, looking for SERRORs + * Scan the PCI device list for one pass, looking for SERRORs * Master Parity ERRORS or Parity ERRORs on primary or secondary devices */ static inline void edac_pci_dev_parity_iterator(pci_parity_check_fn_t fn) @@ -535,22 +662,22 @@ static inline void edac_pci_dev_parity_iterator(pci_parity_check_fn_t fn) */ void edac_pci_do_parity_check(void) { - unsigned long flags; int before_count; debugf3("%s()\n", __func__); + /* if policy has PCI check off, leave now */ if (!check_pci_errors) return; before_count = atomic_read(&pci_parity_count); /* scan all PCI devices looking for a Parity Error on devices and - * bridges + * bridges. + * The iterator calls pci_get_device() which might sleep, thus + * we cannot disable interrupts in this scan. */ - local_irq_save(flags); edac_pci_dev_parity_iterator(edac_pci_dev_parity_test); - local_irq_restore(flags); /* Only if operator has selected panic on PCI Error */ if (edac_pci_get_panic_on_pe()) { @@ -560,6 +687,12 @@ void edac_pci_do_parity_check(void) } } +/* + * edac_pci_clear_parity_errors + * + * function to perform an iteration over the PCI devices + * and clearn their current status + */ void edac_pci_clear_parity_errors(void) { /* Clear any PCI bus parity errors that devices initially have logged @@ -567,6 +700,12 @@ void edac_pci_clear_parity_errors(void) */ edac_pci_dev_parity_iterator(edac_pci_dev_parity_clear); } + +/* + * edac_pci_handle_pe + * + * Called to handle a PARITY ERROR event + */ void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg) { @@ -584,9 +723,14 @@ void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg) */ edac_pci_do_parity_check(); } - EXPORT_SYMBOL_GPL(edac_pci_handle_pe); + +/* + * edac_pci_handle_npe + * + * Called to handle a NON-PARITY ERROR event + */ void edac_pci_handle_npe(struct edac_pci_ctl_info *pci, const char *msg) { @@ -604,7 +748,6 @@ void edac_pci_handle_npe(struct edac_pci_ctl_info *pci, const char *msg) */ edac_pci_do_parity_check(); } - EXPORT_SYMBOL_GPL(edac_pci_handle_npe); /*