Remove percpu comment

dm-compress/lbd.c

@@ -45,34 +45,6 @@ struct lbd {
     u32                         c_len;
 };
 
-/*
- * Allocating lz4_wrkmem percpu:
- *
- * If the alloc is per-instance, it would need to be allocated in compress.c
- * and passed around.  The easiest way to pass it around is likely to make it
- * part of a struct.  We can't use struct compress because that is private.
- * So we would need to create a struct (say, compress_percpu).
- *
- * If the alloc is global, we can just declare it file-local.  But it would
- * need to be the largest possible size.  Which means we probably don't want
- * to use alloc_percpu_gfp() directly, because 1mb chunks are probably not
- * that common.  So suppose we allocate a percpu vector of page ptrs.
- *
- * #define COMPRESS_MAX_INPUT_SIZE (1 << LBLK_SHIFT_MAX)
- * #define COMPRESS_LZ4_BOUND      LZ4_COMPRESSBOUND(COMPRESS_MAX_INPUT_SIZE)
- * #define WRKMEM_PAGES            DIV_ROUND_UP(COMPRESS_LZ4_BOUND, PAGE_SIZE)
- * typedef struct page*[WRKMEM_PAGES] lz4_wrkmem_pagev_t;
- *
- * g_lz4_wrkmem = alloc_percpu_gfp(lz4_wrkmem_pagev_t, GFP_IO);
- *
- * That's not bad at all.  But how do we alloc (and free) the actual pages?
- *
- * pagev = get_cpu_var(g_lz4_wrkmem);
- * put_cpu_var(pagev);
- *
- * free_percpu(g_lz4_wrkmem);
- */
-
 static inline bool
 lblk_is_zeros(struct cbd_params* params, struct lbd* lbd)
 {