Re: [PATCH] kprobe: increase kprobe_hash_table size

[Andrew Morton <akpm@linux-foundation.org>]

On Fri, 07 Nov 2008 21:33:49 -0500 Masami Hiramatsu <mhiramat@redhat.com> wrote:

> Not really. Hmm, I have to investigate more on this problem.

OK ;)

Meanwhile, how does this look?



From: Andrew Morton <akpm@linux-foundation.org>

We only need the cacheline padding on SMP kernels.  Saves 6k:

   text    data     bss     dec     hex filename
   5713     388    2632    8733    221d kernel/kprobes.o
   5713     388    8840   14941    3a5d kernel/kprobes.o

Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/kprobes.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN kernel/kprobes.c~a kernel/kprobes.c
--- a/kernel/kprobes.c~a
+++ a/kernel/kprobes.c
@@ -72,7 +72,7 @@ static bool kprobe_enabled;
 DEFINE_MUTEX(kprobe_mutex);		/* Protects kprobe_table */
 static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
 static struct {
-	spinlock_t lock ____cacheline_aligned;
+	spinlock_t lock ____cacheline_aligned_in_smp;
 } kretprobe_table_locks[KPROBE_TABLE_SIZE];
 
 static spinlock_t *kretprobe_table_lock_ptr(unsigned long hash)
_