On 2023/05/11 22:54, Alexander Lobakin wrote: [...] >> @@ -777,12 +783,44 @@ EXPORT_SYMBOL(kmalloc_size_roundup); >> #define KMALLOC_RCL_NAME(sz) >> #endif >> >> +#ifdef CONFIG_RANDOM_KMALLOC_CACHES >> +#define __KMALLOC_RANDOM_CONCAT(a, b, c) a ## b ## c >> +#define KMALLOC_RANDOM_NAME(N, sz) __KMALLOC_RANDOM_CONCAT(KMALLOC_RANDOM_, N, _NAME)(sz) >> +#if CONFIG_RANDOM_KMALLOC_CACHES_BITS >= 1 >> +#define KMALLOC_RANDOM_1_NAME(sz) .name[KMALLOC_RANDOM_START + 0] = "kmalloc-random-01-" #sz, >> +#define KMALLOC_RANDOM_2_NAME(sz) KMALLOC_RANDOM_1_NAME(sz) .name[KMALLOC_RANDOM_START + 1] = "kmalloc-random-02-" #sz, >> +#endif >> +#if CONFIG_RANDOM_KMALLOC_CACHES_BITS >= 2 >> +#define KMALLOC_RANDOM_3_NAME(sz) KMALLOC_RANDOM_2_NAME(sz) .name[KMALLOC_RANDOM_START + 2] = "kmalloc-random-03-" #sz, >> +#define KMALLOC_RANDOM_4_NAME(sz) KMALLOC_RANDOM_3_NAME(sz) .name[KMALLOC_RANDOM_START + 3] = "kmalloc-random-04-" #sz, >> +#endif >> +#if CONFIG_RANDOM_KMALLOC_CACHES_BITS >= 3 >> +#define KMALLOC_RANDOM_5_NAME(sz) KMALLOC_RANDOM_4_NAME(sz) .name[KMALLOC_RANDOM_START + 4] = "kmalloc-random-05-" #sz, >> +#define KMALLOC_RANDOM_6_NAME(sz) KMALLOC_RANDOM_5_NAME(sz) .name[KMALLOC_RANDOM_START + 5] = "kmalloc-random-06-" #sz, >> +#define KMALLOC_RANDOM_7_NAME(sz) KMALLOC_RANDOM_6_NAME(sz) .name[KMALLOC_RANDOM_START + 6] = "kmalloc-random-07-" #sz, >> +#define KMALLOC_RANDOM_8_NAME(sz) KMALLOC_RANDOM_7_NAME(sz) .name[KMALLOC_RANDOM_START + 7] = "kmalloc-random-08-" #sz, >> +#endif >> +#if CONFIG_RANDOM_KMALLOC_CACHES_BITS >= 4 >> +#define KMALLOC_RANDOM_9_NAME(sz) KMALLOC_RANDOM_8_NAME(sz) .name[KMALLOC_RANDOM_START + 8] = "kmalloc-random-09-" #sz, >> +#define KMALLOC_RANDOM_10_NAME(sz) KMALLOC_RANDOM_9_NAME(sz) .name[KMALLOC_RANDOM_START + 9] = "kmalloc-random-10-" #sz, >> +#define KMALLOC_RANDOM_11_NAME(sz) KMALLOC_RANDOM_10_NAME(sz) .name[KMALLOC_RANDOM_START + 10] = "kmalloc-random-11-" #sz, >> +#define KMALLOC_RANDOM_12_NAME(sz) KMALLOC_RANDOM_11_NAME(sz) .name[KMALLOC_RANDOM_START + 11] = "kmalloc-random-12-" #sz, >> +#define KMALLOC_RANDOM_13_NAME(sz) KMALLOC_RANDOM_12_NAME(sz) .name[KMALLOC_RANDOM_START + 12] = "kmalloc-random-13-" #sz, >> +#define KMALLOC_RANDOM_14_NAME(sz) KMALLOC_RANDOM_13_NAME(sz) .name[KMALLOC_RANDOM_START + 13] = "kmalloc-random-14-" #sz, >> +#define KMALLOC_RANDOM_15_NAME(sz) KMALLOC_RANDOM_14_NAME(sz) .name[KMALLOC_RANDOM_START + 14] = "kmalloc-random-15-" #sz, >> +#define KMALLOC_RANDOM_16_NAME(sz) KMALLOC_RANDOM_15_NAME(sz) .name[KMALLOC_RANDOM_START + 15] = "kmalloc-random-16-" #sz, > > This all can be compressed. Only two things are variables here, so > > #define KMALLOC_RANDOM_N_NAME(cur, prev, sz) \ > KMALLOC_RANDOM_##prev##_NAME(sz), \ > .name[KMALLOC_RANDOM_START + prev] = \ > "kmalloc-random-##cur##-" #sz > > #define KMALLOC_RANDOM_16_NAME(sz) KMALLOC_RANDOM_N_NAME(16, 15, sz) > I tried this way of implementation but it didn't work: it did not propagate from 16 to 1, but stopped in the middle. I think it's because the macro is somehow (indirectly) self-referential and the preprocessor won't expand it. Check this for more info: https://gcc.gnu.org/onlinedocs/cpp/Self-Referential-Macros.html > Also I'd rather not put commas ',' at the end of each macro, they're > usually put outside where the macro is used. It seems here we have to put commas at the end. Not only it's to align with how KMALLOC_{RCL,CGROUP,DMA}_NAME are implemented, but also otherwise the expansion of INIT_KMALLOC_INFO would in some cases be like: { .name[KMALLOC_NORMAL] = "kmalloc-" #__short_size, , // an empty entry with a comma } which would cause compilation error in kmalloc_info[]'s initialization. >> +#endif >> +#else // CONFIG_RANDOM_KMALLOC_CACHES >> +#define KMALLOC_RANDOM_NAME(N, sz) >> +#endif >> + >> #define INIT_KMALLOC_INFO(__size, __short_size) \ >> { \ >> .name[KMALLOC_NORMAL] = "kmalloc-" #__short_size, \ >> KMALLOC_RCL_NAME(__short_size) \ >> KMALLOC_CGROUP_NAME(__short_size) \ >> KMALLOC_DMA_NAME(__short_size) \ >> + KMALLOC_RANDOM_NAME(CONFIG_RANDOM_KMALLOC_CACHES_NR, __short_size) \ > > Can't those names be __initconst and here you'd just do one loop from 1 > to KMALLOC_CACHES_NR, which would assign names? I'm not sure compilers > will expand that one to a compile-time constant and assigning 69 > different string pointers per one kmalloc size is a bit of a waste to me. I'm not sure if I understand the question correctly, but I believe these names have been __initconst since kmalloc_info[] is already marked with it. Please let me know if it doesn't answer your question. >> .size = __size, \ >> } >> >> @@ -878,6 +916,11 @@ new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags) >> flags |= SLAB_CACHE_DMA; >> } >> >> +#ifdef CONFIG_RANDOM_KMALLOC_CACHES >> + if (type >= KMALLOC_RANDOM_START && type <= KMALLOC_RANDOM_END) >> + flags |= SLAB_RANDOMSLAB; >> +#endif >> + >> kmalloc_caches[type][idx] = create_kmalloc_cache( >> kmalloc_info[idx].name[type], >> kmalloc_info[idx].size, flags, 0, >> @@ -904,7 +947,7 @@ void __init create_kmalloc_caches(slab_flags_t flags) >> /* >> * Including KMALLOC_CGROUP if CONFIG_MEMCG_KMEM defined >> */ >> - for (type = KMALLOC_NORMAL; type < NR_KMALLOC_TYPES; type++) { >> + for (type = KMALLOC_RANDOM_START; type < NR_KMALLOC_TYPES; type++) { > > Can't we just define something like __KMALLOC_TYPE_START at the > beginning of the enum to not search for all such places each time > something new is added? Yeah I'm okay with this. Before I apply this change I would like to know more opinions (especially from the maintainers) about it. > >> for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) { >> if (!kmalloc_caches[type][i]) >> new_kmalloc_cache(i, type, flags); >> @@ -922,6 +965,9 @@ void __init create_kmalloc_caches(slab_flags_t flags) >> new_kmalloc_cache(2, type, flags); >> } >> } >> +#ifdef CONFIG_RANDOM_KMALLOC_CACHES >> + random_kmalloc_seed = get_random_u64(); >> +#endif >> >> /* Kmalloc array is now usable */ >> slab_state = UP; >> @@ -957,7 +1003,7 @@ void *__do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller >> return ret; >> } >> >> - s = kmalloc_slab(size, flags); >> + s = kmalloc_slab(size, flags, caller); >> >> if (unlikely(ZERO_OR_NULL_PTR(s))) >> return s; > > Thanks, > Olek
