The patch titled
Add ability to keep track of callers of symbol_(get|put) (update)
has been removed from the -mm tree. Its filename was
add-ability-to-keep-track-of-callers-of-symbol_getput-update.patch
This patch was dropped because it was folded into add-ability-to-keep-track-of-callers-of-symbol_getput.patch
------------------------------------------------------
Subject: Add ability to keep track of callers of symbol_(get|put) (update)
From: Trent Piepho <xyzzy@xxxxxxxxxxxxx>
Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/module.h | 2
kernel/module.c | 99 +++++++++++++++++++++++++++------------
2 files changed, 70 insertions(+), 31 deletions(-)
diff -puN include/linux/module.h~add-ability-to-keep-track-of-callers-of-symbol_getput-update include/linux/module.h
--- a/include/linux/module.h~add-ability-to-keep-track-of-callers-of-symbol_getput-update
+++ a/include/linux/module.h
@@ -169,7 +169,7 @@ struct notifier_block;
/* Get/put a kernel symbol (calls must be symmetric) */
void *__symbol_get(const char *symbol, struct module *user);
void *__symbol_get_gpl(const char *symbol);
-#define symbol_get(x) ((typeof(&x))(__symbol_get(MODULE_SYMBOL_PREFIX#x, \
+#define symbol_get(x) ((typeof(&x))(__symbol_get(MODULE_SYMBOL_PREFIX #x, \
THIS_MODULE)))
#ifndef __GENKSYMS__
diff -puN kernel/module.c~add-ability-to-keep-track-of-callers-of-symbol_getput-update kernel/module.c
--- a/kernel/module.c~add-ability-to-keep-track-of-callers-of-symbol_getput-update
+++ a/kernel/module.c
@@ -518,8 +518,10 @@ struct module_use
int count;
};
-/* Does a already use b? Return NULL if it doesn't, a pointer to the
- relevant module_use structure if it does. */
+/*
+ * Does a already use b? Return NULL if it doesn't, a pointer to the
+ * relevant module_use structure if it does.
+ */
static struct module_use *already_uses(struct module *a, struct module *b)
{
struct module_use *use;
@@ -534,18 +536,31 @@ static struct module_use *already_uses(s
return NULL;
}
-/* Module a uses b
- If inc is set, then the use count will be incremented. */
+/*
+ * Module a uses b. If module a is a _new_ user of module b, module b's ref
+ * count will be incremented. If a is not a new user of b, and inc is true,
+ * then the use count (i.e. how many times a uses b) will be incremented. If a
+ * is NULL, then the ref count will just always be incremented.
+ */
static int use_module(struct module *a, struct module *b, bool inc)
{
struct module_use *use;
int no_warn;
- if (b == NULL) return 1;
+ if (b == NULL)
+ return 1;
- if ((use = already_uses(a, b))) {
- if (inc) use->count++;
- DEBUGP("%s: %s already used %s, count now at %d\n", __FUNCTION__, a->name, b->name, use->count);
+ DEBUGP("%s: %s uses %s\n", __FUNCTION__, a?a->name:"(unknown)",
+ b->name);
+ if (a == NULL)
+ return strong_try_module_get(b);
+
+ use = already_uses(a, b);
+ if (use) {
+ if (inc)
+ use->count++;
+ DEBUGP("%s: %s already used %s, count now at %d\n",
+ __FUNCTION__, a->name, b->name, use->count);
return 1;
}
@@ -567,21 +582,39 @@ static int use_module(struct module *a,
return 1;
}
-/* Module a is "un-using" module b. The use count is decremented, and if
- it reaches zero the module_use is removed. Returns number of
- remaining uses. */
+/*
+ * Module a is "un-using" module b. The use count is decremented, and if
+ * it reaches zero the module_use is removed and module b's ref-count is
+ * decremented. Returns number of remaining uses. If a is NULL, then
+ * just decrement b's ref count.
+ */
static int unuse_module(struct module *a, struct module *b)
{
- struct module_use *use = already_uses(a, b);
- DEBUGP("%s: unuse %s by %s\n", __FUNCTION__, b->name, a->name);
+ struct module_use *use;
- BUG_ON(!use);
- DEBUGP("%s: %s used %s %d time(s)\n", __FUNCTION__, a->name, b->name, use->count);
- if (! --(use->count)) {
- DEBUGP("%s: removing module_use structure and sysfs link\n", __FUNCTION__);
+ DEBUGP("%s: unuse %s by %s\n", __FUNCTION__, b->name,
+ a?a->name:"(unknown)");
+ if (!a) {
+ module_put(b);
+ return 0;
+ }
+
+ use = already_uses(a, b);
+ if (!use) {
+ printk(KERN_ERR "module %s trying to un-use a module, %s, which "
+ "it is not using", a->name, b->name);
+ BUG();
+ }
+
+ DEBUGP("%s: %s used %s %d time(s)\n", __FUNCTION__,
+ a->name, b->name, use->count);
+ if (!--(use->count)) {
+ DEBUGP("%s: removing module_use structure and sysfs link\n",
+ __FUNCTION__);
list_del(&use->list);
kfree(use);
sysfs_remove_link(b->holders_dir, a->name);
+ module_put(b);
return 0;
}
return use->count;
@@ -598,9 +631,14 @@ static void module_unload_free(struct mo
list_for_each_entry(use, &i->modules_which_use_me, list) {
if (use->module_which_uses == mod) {
DEBUGP("%s unusing %s\n", mod->name, i->name);
- if (unuse_module(mod, i))
- printk(KERN_ERR "%s unloading but still has uses of %s\n", mod->name, i->name);
- module_put(i);
+ if (unuse_module(mod, i)) {
+ /* Someone messed up! */
+ printk(KERN_ERR "module %s unloading "
+ "but still has uses of %s\n",
+ mod->name, i->name);
+ while (unuse_module(mod, i))
+ ;
+ }
/* There can be at most one match. */
break;
}
@@ -789,15 +827,14 @@ void __symbol_put(const char *symbol, st
unsigned long flags;
const unsigned long *crc;
- DEBUGP("%s: putting %s by %s\n", __FUNCTION__, symbol, user?user->name:"(unknown)");
+ DEBUGP("%s: putting symbol %s by %s\n", __FUNCTION__, symbol,
+ user?user->name:"(unknown)");
spin_lock_irqsave(&modlist_lock, flags);
if (!__find_symbol(symbol, &owner, &crc, 1))
BUG();
- /* If the symbol is owned by a module, put it if no user was
- specified or if this is the last of user's uses of the module. */
- if (owner && (!user || !unuse_module(user, owner)))
- module_put(owner);
+ if (owner)
+ unuse_module(user, owner);
spin_unlock_irqrestore(&modlist_lock, flags);
}
EXPORT_SYMBOL(__symbol_put);
@@ -807,15 +844,15 @@ void __symbol_put_addr(void *addr, struc
struct module *modaddr;
unsigned long flags;
- DEBUGP("%s: putting %p by %s\n", __FUNCTION__, addr, user?user->name:"(unknown)");
+ DEBUGP("%s: putting %p by %s\n", __FUNCTION__, addr,
+ user?user->name:"(unknown)");
if (core_kernel_text((unsigned long)addr))
return;
if (!(modaddr = module_text_address((unsigned long)addr)))
BUG();
spin_lock_irqsave(&modlist_lock, flags);
- if (!user || !unuse_module(user, modaddr))
- module_put(modaddr);
+ unuse_module(user, modaddr);
spin_unlock_irqrestore(&modlist_lock, flags);
}
EXPORT_SYMBOL_GPL(__symbol_put_addr);
@@ -1267,10 +1304,12 @@ void *__symbol_get(const char *symbol, s
unsigned long value, flags;
const unsigned long *crc;
- DEBUGP("%s: get symbol %s by %s\n", __FUNCTION__, symbol, user?user->name:"(unknown)");
+ DEBUGP("%s: get symbol %s by %s\n", __FUNCTION__, symbol,
+ user?user->name:"(unknown)");
spin_lock_irqsave(&modlist_lock, flags);
value = __find_symbol(symbol, &owner, &crc, 1);
- DEBUGP("%s: symbol %s is 0WN3D by %s\n", __FUNCTION__, symbol, owner?owner->name:"yer mom");
+ DEBUGP("%s: symbol %s is 0WN3D by %s\n", __FUNCTION__, symbol,
+ value?(owner?owner->name:"yer mom"):"no one");
if (value && owner && !use_module(user, owner, true))
value = 0;
spin_unlock_irqrestore(&modlist_lock, flags);
_
Patches currently in -mm which might be from xyzzy@xxxxxxxxxxxxx are
origin.patch
git-dvb.patch
fix-constant-folding-and-poor-optimization-in-byte-swapping.patch
add-ability-to-keep-track-of-callers-of-symbol_getput.patch
add-ability-to-keep-track-of-callers-of-symbol_getput-update.patch
update-mtd-use-of-symbol_getput.patch
update-dvb-use-of-symbol_getput.patch
-
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