From 495bd532ab4aaef46b57094d59707bad91e6ec25 Mon Sep 17 00:00:00 2001 From: Brian Behlendorf Date: Wed, 23 Mar 2011 15:45:55 -0700 Subject: [PATCH] Linux shrinker compat The Linux shrinker has gone through three API changes since 2.6.22. Rather than force every caller to understand all three APIs this change consolidates the compatibility code in to the mm-compat.h header. The caller then can then use a single spl provided shrinker API which does the right thing for your kernel. SPL_SHRINKER_CALLBACK_PROTO(shrinker_callback, cb, nr_to_scan, gfp_mask); SPL_SHRINKER_DECLARE(shrinker_struct, shrinker_callback, seeks); spl_register_shrinker(&shrinker_struct); spl_unregister_shrinker(&&shrinker_struct); spl_exec_shrinker(&shrinker_struct, nr_to_scan, gfp_mask); --- include/linux/mm_compat.h | 46 +++++++++++++++++++++++++++++++++++ module/spl/spl-kmem.c | 50 +++++++-------------------------------- 2 files changed, 55 insertions(+), 41 deletions(-) diff --git a/include/linux/mm_compat.h b/include/linux/mm_compat.h index 5c5198b90fde..7e2f6b8a5805 100644 --- a/include/linux/mm_compat.h +++ b/include/linux/mm_compat.h @@ -56,4 +56,50 @@ extern invalidate_inodes_t invalidate_inodes_fn; #define invalidate_inodes(sb) invalidate_inodes_fn(sb) #endif /* HAVE_INVALIDATE_INODES */ +#ifdef HAVE_SET_SHRINKER +typedef struct spl_shrinker { + struct shrinker *shrinker; + shrinker_t fn; + int seeks; +} spl_shrinker_t; + +static inline void +spl_register_shrinker(spl_shrinker_t *ss) +{ + ss->shrinker = set_shrinker(ss->seeks, ss->fn); +} + +static inline void +spl_unregister_shrinker(spl_shrinker_t *ss) +{ + remove_shrinker(ss->shrinker); +} + +# define SPL_SHRINKER_DECLARE(s, x, y) \ + static spl_shrinker_t s = { .shrinker = NULL, .fn = x, .seeks = y } +# define SPL_SHRINKER_CALLBACK_PROTO(fn, x, y, z) \ + static int fn(int y, unsigned int z) +# define spl_exec_shrinker(ss, nr, gfp) \ + ((spl_shrinker_t *)ss)->fn(nr, gfp) + +#else /* HAVE_SET_SHRINKER */ + +# define spl_register_shrinker(x) register_shrinker(x) +# define spl_unregister_shrinker(x) unregister_shrinker(x) +# define SPL_SHRINKER_DECLARE(s, x, y) \ + static struct shrinker s = { .shrink = x, .seeks = y } + +# ifdef HAVE_3ARGS_SHRINKER_CALLBACK +# define SPL_SHRINKER_CALLBACK_PROTO(fn, x, y, z) \ + static int fn(struct shrinker *x, int y, unsigned int z) +# define spl_exec_shrinker(ss, nr, gfp) \ + ((struct shrinker *)ss)->shrink(NULL, nr, gfp) +# else /* HAVE_3ARGS_SHRINKER_CALLBACK */ +# define SPL_SHRINKER_CALLBACK_PROTO(fn, x, y, z) \ + static int fn(int y, unsigned int z) +# define spl_exec_shrinker(ss, nr, gfp) \ + ((struct shrinker *)ss)->shrink(nr, gfp) +# endif /* HAVE_3ARGS_SHRINKER_CALLBACK */ +#endif /* HAVE_SET_SHRINKER */ + #endif /* SPL_MM_COMPAT_H */ diff --git a/module/spl/spl-kmem.c b/module/spl/spl-kmem.c index 2f533bdf619b..87594bde9339 100644 --- a/module/spl/spl-kmem.c +++ b/module/spl/spl-kmem.c @@ -819,21 +819,10 @@ struct rw_semaphore spl_kmem_cache_sem; /* Cache list lock */ static int spl_cache_flush(spl_kmem_cache_t *skc, spl_kmem_magazine_t *skm, int flush); -#ifdef HAVE_SET_SHRINKER -static struct shrinker *spl_kmem_cache_shrinker; -#else -# ifdef HAVE_3ARGS_SHRINKER_CALLBACK -static int spl_kmem_cache_generic_shrinker(struct shrinker *shrinker_cb, - int nr_to_scan, unsigned int gfp_mask); -# else -static int spl_kmem_cache_generic_shrinker( - int nr_to_scan, unsigned int gfp_mask); -# endif /* HAVE_3ARGS_SHRINKER_CALLBACK */ -static struct shrinker spl_kmem_cache_shrinker = { - .shrink = spl_kmem_cache_generic_shrinker, - .seeks = KMC_DEFAULT_SEEKS, -}; -#endif /* HAVE_SET_SHRINKER */ +SPL_SHRINKER_CALLBACK_PROTO(spl_kmem_cache_generic_shrinker, + shrinker_cb, nr_to_scan, gfp_mask); +SPL_SHRINKER_DECLARE(spl_kmem_cache_shrinker, + spl_kmem_cache_generic_shrinker, KMC_DEFAULT_SEEKS); static void * kv_alloc(spl_kmem_cache_t *skc, int size, int flags) @@ -1859,14 +1848,8 @@ EXPORT_SYMBOL(spl_kmem_cache_free); * objects should be freed, because Solaris semantics are to free * all available objects we may free more objects than requested. */ -#ifdef HAVE_3ARGS_SHRINKER_CALLBACK -static int -spl_kmem_cache_generic_shrinker(struct shrinker *shrinker_cb, - int nr_to_scan, unsigned int gfp_mask) -#else -static int -spl_kmem_cache_generic_shrinker(int nr_to_scan, unsigned int gfp_mask) -#endif /* HAVE_3ARGS_SHRINKER_CALLBACK */ +SPL_SHRINKER_CALLBACK_PROTO(spl_kmem_cache_generic_shrinker, + shrinker_cb, nr_to_scan, gfp_mask) { spl_kmem_cache_t *skc; int unused = 0; @@ -1930,11 +1913,7 @@ EXPORT_SYMBOL(spl_kmem_cache_reap_now); void spl_kmem_reap(void) { -#ifdef HAVE_3ARGS_SHRINKER_CALLBACK - spl_kmem_cache_generic_shrinker(NULL, KMC_REAP_CHUNK, GFP_KERNEL); -#else - spl_kmem_cache_generic_shrinker(KMC_REAP_CHUNK, GFP_KERNEL); -#endif /* HAVE_3ARGS_SHRINKER_CALLBACK */ + spl_exec_shrinker(&spl_kmem_cache_shrinker, KMC_REAP_CHUNK, GFP_KERNEL); } EXPORT_SYMBOL(spl_kmem_reap); @@ -2135,14 +2114,7 @@ spl_kmem_init(void) init_rwsem(&spl_kmem_cache_sem); INIT_LIST_HEAD(&spl_kmem_cache_list); -#ifdef HAVE_SET_SHRINKER - spl_kmem_cache_shrinker = set_shrinker(KMC_DEFAULT_SEEKS, - spl_kmem_cache_generic_shrinker); - if (spl_kmem_cache_shrinker == NULL) - SRETURN(rc = -ENOMEM); -#else - register_shrinker(&spl_kmem_cache_shrinker); -#endif + spl_register_shrinker(&spl_kmem_cache_shrinker); #ifdef DEBUG_KMEM kmem_alloc_used_set(0); @@ -2178,11 +2150,7 @@ spl_kmem_fini(void) #endif /* DEBUG_KMEM */ SENTRY; -#ifdef HAVE_SET_SHRINKER - remove_shrinker(spl_kmem_cache_shrinker); -#else - unregister_shrinker(&spl_kmem_cache_shrinker); -#endif + spl_unregister_shrinker(&spl_kmem_cache_shrinker); SEXIT; }