More clarification - this:
---
diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c
index ec945294626a..06510c8c8281 100644
--- a/net/sched/cls_fw.c
+++ b/net/sched/cls_fw.c
@@ -22,12 +22,12 @@
#include <net/pkt_cls.h>
#include <net/sch_generic.h>
-#define HTSIZE 256
+#define HTSIZE 4096
struct fw_head {
+ struct rcu_head rcu;
u32 mask;
struct fw_filter __rcu *ht[HTSIZE];
- struct rcu_head rcu;
};
----
Does not fix it..
cheers,
jamal
On 2020-08-07 11:16 a.m., Jamal Hadi Salim wrote:
Made this small change:
------
diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c
index ec945294626a..75d43ed10cd8 100644
--- a/net/sched/cls_fw.c
+++ b/net/sched/cls_fw.c
@@ -22,7 +22,7 @@
#include <net/pkt_cls.h>
#include <net/sch_generic.h>
-#define HTSIZE 256
+#define HTSIZE 4096
struct fw_head {
u32 mask;
---------
Generated compile errors as follows:
------------
DESCEND objtool
CALL scripts/atomic/check-atomics.sh
CALL scripts/checksyscalls.sh
CHK include/generated/compile.h
CC net/sched/cls_fw.o
In file included from ./include/linux/export.h:43:0,
from ./include/linux/linkage.h:7,
from ./include/linux/kernel.h:8,
from ./include/linux/list.h:9,
from ./include/linux/module.h:12,
from net/sched/cls_fw.c:13:
net/sched/cls_fw.c: In function ‘fw_destroy’:
./include/linux/compiler.h:392:38: error: call to
‘__compiletime_assert_415’ declared with attribute error: BUILD_BUG_ON
failed: !__is_kfree_rcu_offset(__builtin_offsetof(typeof(*(head)), rcu))
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
./include/linux/compiler.h:373:4: note: in definition of macro
‘__compiletime_assert’
prefix ## suffix(); \
^~~~~~
./include/linux/compiler.h:392:2: note: in expansion of macro
‘_compiletime_assert’
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^~~~~~~~~~~~~~~~~~~
./include/linux/build_bug.h:39:37: note: in expansion of macro
‘compiletime_assert’
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^~~~~~~~~~~~~~~~~~
./include/linux/build_bug.h:50:2: note: in expansion of macro
‘BUILD_BUG_ON_MSG’
BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
^~~~~~~~~~~~~~~~
./include/linux/rcupdate.h:840:3: note: in expansion of macro
‘BUILD_BUG_ON’
BUILD_BUG_ON(!__is_kfree_rcu_offset(offset)); \
^~~~~~~~~~~~
./include/linux/rcupdate.h:875:3: note: in expansion of macro ‘__kfree_rcu’
__kfree_rcu(&((___p)->rhf), offsetof(typeof(*(ptr)), rhf)); \
^~~~~~~~~~~
net/sched/cls_fw.c:151:2: note: in expansion of macro ‘kfree_rcu’
kfree_rcu(head, rcu);
^~~~~~~~~
scripts/Makefile.build:280: recipe for target 'net/sched/cls_fw.o' failed
make[2]: *** [net/sched/cls_fw.o] Error 1
scripts/Makefile.build:497: recipe for target 'net/sched' failed
make[1]: *** [net/sched] Error 2
Makefile:1771: recipe for target 'net' failed
make: *** [net] Error 2
make: *** Waiting for unfinished jobs....
----------------
Gets fixed if i reduce the hash buckets of course.
Looking at include/linux/rcupdate.h I see:
------
/*
* Does the specified offset indicate that the corresponding rcu_head
* structure can be handled by kfree_rcu()?
*/
#define __is_kfree_rcu_offset(offset) ((offset) < 4096)
------
I am guessing the hash table got too large.
Smells like hard coded expectation?
How to fix?
cheers,
jamal
