In message <20030520035322.27211c07.akpm@digeo.com> you write:
> Rusty Russell <rusty@rustcorp.com.au> wrote:
> >
> > [ Untested on ia64, but fairly trivial if I've broken something ].
> >
> > Name: Unification of per-cpu headers for non-SMP
> > Author: Rusty Russell
> > Status: Trivial
>
> I applied all these to the ppc64 kernel (you missed ppc64 btw) and it dies.
>
> Quite late in boot, during floppy_init->init_disk_stats->alloc_percpu.
>
> I'm reduced to debugging with printk on ppc64. __alloc_percpu() calls
> new_block(), loops around and then dies in here:
Hmm, Works For Me(TM). Here's my test code: change
init_alloc_percpu() to call test_percpu() explicitly at the end (so
before you hit the current bug).
I'll test on bk14 here, and if that passes I'll seek a PPC64 box...
Thanks!
Rusty.
Name: kmalloc testing patch
Author: Rusty Russell
Status: Tested on 2.5.69-bk13
Depends: Misc/kmalloc_percpu-full.patch.gz
D: This adds simple test code to kmalloc percpu.
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal working-2.5.69-bk13-kmalloc_percpu-full/mm/percpu.c working-2.5.69-bk13-kmalloc_percpu-debug/mm/percpu.c
--- working-2.5.69-bk13-kmalloc_percpu-full/mm/percpu.c 2003-05-20 12:54:21.000000000 +1000
+++ working-2.5.69-bk13-kmalloc_percpu-debug/mm/percpu.c 2003-05-20 12:53:47.000000000 +1000
@@ -245,6 +245,159 @@ void free_percpu(const void *freeme)
BUG();
}
+#if 1
+#include <linux/random.h>
+
+static void check_values(unsigned int *ptrs[],
+ unsigned int sizes[],
+ unsigned int num)
+{
+ unsigned int cpu, i;
+ unsigned char *ptr;
+
+ if (!ptrs[num])
+ return;
+
+ for (cpu = 0; cpu < NR_CPUS; cpu++) {
+ ptr = (unsigned char *)per_cpu_ptr(ptrs[num], cpu);
+ for (i = 0; i < sizes[num]; i++) {
+ if (ptr[i] != (unsigned char)(num + cpu))
+ BUG();
+ }
+ }
+}
+
+static void check_blocklen(void)
+{
+ struct pcpu_block *i;
+ unsigned int count = 0;
+
+ list_for_each_entry(i, &pcpu_blocks, list)
+ count++;
+
+ printk("Total blocks = %u\n", count);
+}
+
+static void dump_blocks(const char *start_or_end)
+{
+ struct pcpu_block *i;
+
+ list_for_each_entry(i, &pcpu_blocks, list) {
+ int expected_blocks = 1;
+
+ if (i->base_ptr == percpu_base)
+ expected_blocks = 2;
+ if (i->num_used != expected_blocks) {
+ printk("Block %p has %u subs at %s\n",
+ i->base_ptr, i->num_used, start_or_end);
+ }
+ }
+}
+
+static void mymemset(void *ptr, int c, unsigned long len)
+{
+ unsigned char *p = ptr;
+ while (len > 0) {
+ *p = c;
+ p++;
+ len--;
+ }
+}
+
+static int random(void)
+{
+ unsigned short s;
+
+ get_random_bytes(&s, sizeof(s));
+ return s;
+}
+
+static int test_percpu(void)
+{
+ unsigned int i, allocs, frees;
+ unsigned int *ptr;
+ static unsigned int *ptrs[PERCPU_MAX], sizes[PERCPU_MAX];
+
+ dump_blocks("start");
+ allocs = frees = 0;
+ ptr = __alloc_percpu(4, 4); allocs++;
+ printk("This cpu = %p (%u)\n",
+ __get_cpu_ptr(ptr), *__get_cpu_ptr(ptr));
+ for (i = 0; i < NR_CPUS; i++) {
+ printk("&ptr[i] == %p (%u)\n",
+ per_cpu_ptr(ptr, i), *per_cpu_ptr(ptr, i));
+ *per_cpu_ptr(ptr, i) = i;
+ }
+ free_percpu(ptr); frees++;
+
+ BUG_ON(allocs != frees);
+
+ for (i = 4; i < PERCPU_MAX; i+=27) {
+ unsigned int j;
+ ptrs[i] = __alloc_percpu(i, 4); allocs++;
+ for (j = 0; j < NR_CPUS; j++) {
+ mymemset(per_cpu_ptr(ptrs[i], j), 0, i);
+ *per_cpu_ptr(ptrs[i], j) = i;
+ }
+ }
+
+ for (i = 4; i < PERCPU_MAX; i+=27) {
+ unsigned int j;
+ for (j = 0; j < NR_CPUS; j++)
+ if (*per_cpu_ptr(ptrs[i], j) != i)
+ BUG();
+ }
+ for (i = 4; i < PERCPU_MAX; i+=27) {
+ free_percpu(ptrs[i]); frees++;
+ ptrs[i] = NULL;
+ }
+
+ BUG_ON(allocs != frees);
+
+ /* Randomized test. */
+ for (i = 0; i < 10000; i++) {
+ unsigned int j = random() % PERCPU_MAX;
+ if (!ptrs[j]) {
+ unsigned int cpu;
+
+ sizes[j] = random() % PERCPU_MAX;
+ if (sizes[j] < 4)
+ sizes[j] = 4;
+ ptrs[j] = __alloc_percpu(sizes[j], 1<<(random()%L1_CACHE_SHIFT));
+ allocs++;
+
+ for (cpu = 0; cpu < NR_CPUS; cpu++)
+ memset(per_cpu_ptr(ptrs[j], cpu), j+cpu,
+ sizes[j]);
+ } else {
+ if (random() % 1000 == 0) {
+ printk("c\n");
+ for (j = 0; j < PERCPU_MAX; j++)
+ check_values(ptrs, sizes, j);
+ } else {
+ check_values(ptrs, sizes, j);
+ free_percpu(ptrs[j]); frees++;
+ ptrs[j] = NULL;
+ }
+ }
+ if (i % (10000/10) == 0)
+ printk(".\n");
+ }
+ check_blocklen();
+
+ for (i = 0; i < PERCPU_MAX; i++) {
+ if (ptrs[i]) {
+ free_percpu(ptrs[i]); frees++;
+ ptrs[i] = NULL;
+ }
+ }
+ BUG_ON(allocs != frees);
+ dump_blocks("end");
+ return 0;
+}
+late_initcall(test_percpu);
+#endif
+
unsigned long __per_cpu_offset[NR_CPUS];
EXPORT_SYMBOL(__per_cpu_offset);
-- Anyone who quotes me in their sig is an idiot. -- Rusty Russell. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Fri May 23 2003 - 22:00:43 EST