The slub_debug=PU,kmalloc-xx cannot work because in the create_kmalloc_caches() the s->name is created after the create_kmalloc_cache() is called. The name is NULL in the create_kmalloc_cache() so the kmem_cache_flags() would not set the slub_debug flags to the s->flags. The fix here set up a kmalloc_names string array for the initialization purpose and delete the dynamic name creation of kmalloc_caches.
v2->v3 - Adopted suggestion from Andrew Morton to delete the kmalloc-96/192 case and merge the code to single initialization loop. - Redefine the kmalloc_names. - Add the KMALLOC_LOOP_LOW as the for loop start index to initialize the kmalloc_caches object. v1->v2 - Adopted suggestion from Christoph to delete the dynamic name creation for kmalloc_caches. Signed-off-by: Gavin Guo <[email protected]> --- include/linux/slab.h | 22 +++++++++++++++++++ mm/slab_common.c | 62 +++++++++++++++++++++++++++++++++------------------- 2 files changed, 61 insertions(+), 23 deletions(-) diff --git a/include/linux/slab.h b/include/linux/slab.h index ffd24c8..96f0ea5 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -153,8 +153,30 @@ size_t ksize(const void *); #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN #define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN #define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN) +/* + * The KMALLOC_LOOP_LOW is the definition for the for loop index start number + * to create the kmalloc_caches object in create_kmalloc_caches(). The first + * and the second are 96 and 192. You can see that in the kmalloc_index(), if + * the KMALLOC_MIN_SIZE <= 32, then return 1 (96). If KMALLOC_MIN_SIZE <= 64, + * then return 2 (192). If the KMALLOC_MIN_SIZE is bigger than 64, we don't + * need to initialize 96 and 192. Go directly to start the KMALLOC_SHIFT_LOW. + */ +#if KMALLOC_MIN_SIZE <= 32 +#define KMALLOC_LOOP_LOW 1 +#elif KMALLOC_MIN_SIZE <= 64 +#define KMALLOC_LOOP_LOW 2 +#else +#define KMALLOC_LOOP_LOW KMALLOC_SHIFT_LOW +#endif + #else #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long) +/* + * The KMALLOC_MIN_SIZE of slub/slab/slob is 2^3/2^5/2^3. So, even slab is used. + * The KMALLOC_MIN_SIZE <= 32. The kmalloc-96 and kmalloc-192 should also be + * initialized. + */ +#define KMALLOC_LOOP_LOW 1 #endif /* diff --git a/mm/slab_common.c b/mm/slab_common.c index 999bb34..05c6439 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -784,6 +784,31 @@ struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags) } /* + * The kmalloc_names is to make slub_debug=,kmalloc-xx option work in the boot + * time. The kmalloc_index() support to 2^26=64MB. So, the final entry of the + * table is kmalloc-67108864. + */ +static struct { + const char *name; + unsigned long size; +} const kmalloc_names[] __initconst = { + {NULL, 0}, {"kmalloc-96", 96}, + {"kmalloc-192", 192}, {"kmalloc-8", 8}, + {"kmalloc-16", 16}, {"kmalloc-32", 32}, + {"kmalloc-64", 64}, {"kmalloc-128", 128}, + {"kmalloc-256", 256}, {"kmalloc-512", 512}, + {"kmalloc-1024", 1024}, {"kmalloc-2048", 2048}, + {"kmalloc-4096", 4096}, {"kmalloc-8192", 8192}, + {"kmalloc-16384", 16384}, {"kmalloc-32768", 32768}, + {"kmalloc-65536", 65536}, {"kmalloc-131072", 131072}, + {"kmalloc-262144", 262144}, {"kmalloc-524288", 524288}, + {"kmalloc-1048576", 1048576}, {"kmalloc-2097152", 2097152}, + {"kmalloc-4194304", 4194304}, {"kmalloc-8388608", 8388608}, + {"kmalloc-16777216", 16777216}, {"kmalloc-33554432", 33554432}, + {"kmalloc-67108864", 67108864} +}; + +/* * Create the kmalloc array. Some of the regular kmalloc arrays * may already have been created because they were needed to * enable allocations for slab creation. @@ -833,39 +858,30 @@ void __init create_kmalloc_caches(unsigned long flags) for (i = 128 + 8; i <= 192; i += 8) size_index[size_index_elem(i)] = 8; } - for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) { + for (i = KMALLOC_LOOP_LOW; i <= KMALLOC_SHIFT_HIGH; i++) { if (!kmalloc_caches[i]) { - kmalloc_caches[i] = create_kmalloc_cache(NULL, - 1 << i, flags); + kmalloc_caches[i] = create_kmalloc_cache( + kmalloc_names[i].name, + kmalloc_names[i].size, + flags); } /* - * Caches that are not of the two-to-the-power-of size. - * These have to be created immediately after the - * earlier power of two caches + * "i == 2" is the "kmalloc-192" case which is the last special + * case for initialization and it's the point to jump to + * allocate the minimize size of the object. In slab allocator, + * the KMALLOC_SHIFT_LOW = 5. So, it needs to skip 2^3 and 2^4 + * and go straight to allocate 2^5. If the ARCH_DMA_MINALIGN is + * defined, it may be larger than 2^5 and here is also the + * trick to skip the empty gap. */ - if (KMALLOC_MIN_SIZE <= 32 && !kmalloc_caches[1] && i == 6) - kmalloc_caches[1] = create_kmalloc_cache(NULL, 96, flags); - - if (KMALLOC_MIN_SIZE <= 64 && !kmalloc_caches[2] && i == 7) - kmalloc_caches[2] = create_kmalloc_cache(NULL, 192, flags); + if (i == 2) + i = (KMALLOC_SHIFT_LOW - 1); } /* Kmalloc array is now usable */ slab_state = UP; - for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) { - struct kmem_cache *s = kmalloc_caches[i]; - char *n; - - if (s) { - n = kasprintf(GFP_NOWAIT, "kmalloc-%d", kmalloc_size(i)); - - BUG_ON(!n); - s->name = n; - } - } - #ifdef CONFIG_ZONE_DMA for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) { struct kmem_cache *s = kmalloc_caches[i]; -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
