+ Chuck Lever, Jeff Layton This was a rather tricky series to get the recipients correct for and my script did not realize that "supporter" was a pseudonym for "maintainer" so you were missed off the original post. Appologies! More context in cover letter: https://lore.kernel.org/all/20241014105514.3206191-1-ryan.roberts@xxxxxxx/ On 14/10/2024 11:58, Ryan Roberts wrote: > To prepare for supporting boot-time page size selection, refactor code > to remove assumptions about PAGE_SIZE being compile-time constant. Code > intended to be equivalent when compile-time page size is active. > > Define NLMSG_GOODSIZE using min() instead of ifdeffery. This will now > evaluate to a compile-time constant for compile-time page size, but > evaluate at run-time when using boot-time page size. > > Rework NAPI small page frag infrastructure so that for boot-time page > size it is compiled in if 4K page size is in the possible range, but > defer deciding to use it to run time when the page size is known. No > change for compile-time page size case. > > Resize cache_defer_hash[] array for PAGE_SIZE_MAX. > > Convert a complex BUILD_BUG_ON() to runtime BUG_ON(). > > Wrap global variables that are initialized with PAGE_SIZE derived values > using DEFINE_GLOBAL_PAGE_SIZE_VAR() so their initialization can be > deferred for boot-time page size builds. > > Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx> > --- > > ***NOTE*** > Any confused maintainers may want to read the cover note here for context: > https://lore.kernel.org/all/20241014105514.3206191-1-ryan.roberts@xxxxxxx/ > > include/linux/netlink.h | 6 +----- > net/core/hotdata.c | 4 ++-- > net/core/skbuff.c | 4 ++-- > net/core/sysctl_net_core.c | 2 +- > net/sunrpc/cache.c | 3 ++- > net/unix/af_unix.c | 2 +- > 6 files changed, 9 insertions(+), 12 deletions(-) > > diff --git a/include/linux/netlink.h b/include/linux/netlink.h > index b332c2048c755..ffa1e94111f89 100644 > --- a/include/linux/netlink.h > +++ b/include/linux/netlink.h > @@ -267,11 +267,7 @@ netlink_skb_clone(struct sk_buff *skb, gfp_t gfp_mask) > * use enormous buffer sizes on recvmsg() calls just to avoid > * MSG_TRUNC when PAGE_SIZE is very large. > */ > -#if PAGE_SIZE < 8192UL > -#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE) > -#else > -#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL) > -#endif > +#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(min(PAGE_SIZE, 8192UL)) > > #define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN) > > diff --git a/net/core/hotdata.c b/net/core/hotdata.c > index d0aaaaa556f22..e1f30e87ba6e9 100644 > --- a/net/core/hotdata.c > +++ b/net/core/hotdata.c > @@ -5,7 +5,7 @@ > #include <net/hotdata.h> > #include <net/proto_memory.h> > > -struct net_hotdata net_hotdata __cacheline_aligned = { > +__DEFINE_GLOBAL_PAGE_SIZE_VAR(struct net_hotdata, net_hotdata, __cacheline_aligned, { > .offload_base = LIST_HEAD_INIT(net_hotdata.offload_base), > .ptype_all = LIST_HEAD_INIT(net_hotdata.ptype_all), > .gro_normal_batch = 8, > @@ -21,5 +21,5 @@ struct net_hotdata net_hotdata __cacheline_aligned = { > .sysctl_max_skb_frags = MAX_SKB_FRAGS, > .sysctl_skb_defer_max = 64, > .sysctl_mem_pcpu_rsv = SK_MEMORY_PCPU_RESERVE > -}; > +}); > EXPORT_SYMBOL(net_hotdata); > diff --git a/net/core/skbuff.c b/net/core/skbuff.c > index 83f8cd8aa2d16..b6c8eee0cc74b 100644 > --- a/net/core/skbuff.c > +++ b/net/core/skbuff.c > @@ -219,9 +219,9 @@ static void skb_under_panic(struct sk_buff *skb, unsigned int sz, void *addr) > #define NAPI_SKB_CACHE_BULK 16 > #define NAPI_SKB_CACHE_HALF (NAPI_SKB_CACHE_SIZE / 2) > > -#if PAGE_SIZE == SZ_4K > +#if PAGE_SIZE_MIN <= SZ_4K && SZ_4K <= PAGE_SIZE_MAX > > -#define NAPI_HAS_SMALL_PAGE_FRAG 1 > +#define NAPI_HAS_SMALL_PAGE_FRAG (PAGE_SIZE == SZ_4K) > #define NAPI_SMALL_PAGE_PFMEMALLOC(nc) ((nc).pfmemalloc) > > /* specialized page frag allocator using a single order 0 page > diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c > index 86a2476678c48..a7a2eb7581bd1 100644 > --- a/net/core/sysctl_net_core.c > +++ b/net/core/sysctl_net_core.c > @@ -33,7 +33,7 @@ static int int_3600 = 3600; > static int min_sndbuf = SOCK_MIN_SNDBUF; > static int min_rcvbuf = SOCK_MIN_RCVBUF; > static int max_skb_frags = MAX_SKB_FRAGS; > -static int min_mem_pcpu_rsv = SK_MEMORY_PCPU_RESERVE; > +static DEFINE_GLOBAL_PAGE_SIZE_VAR(int, min_mem_pcpu_rsv, SK_MEMORY_PCPU_RESERVE); > > static int net_msg_warn; /* Unused, but still a sysctl */ > > diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c > index 95ff747061046..4e682c0cd7586 100644 > --- a/net/sunrpc/cache.c > +++ b/net/sunrpc/cache.c > @@ -573,13 +573,14 @@ EXPORT_SYMBOL_GPL(cache_purge); > */ > > #define DFR_HASHSIZE (PAGE_SIZE/sizeof(struct list_head)) > +#define DFR_HASHSIZE_MAX (PAGE_SIZE_MAX/sizeof(struct list_head)) > #define DFR_HASH(item) ((((long)item)>>4 ^ (((long)item)>>13)) % DFR_HASHSIZE) > > #define DFR_MAX 300 /* ??? */ > > static DEFINE_SPINLOCK(cache_defer_lock); > static LIST_HEAD(cache_defer_list); > -static struct hlist_head cache_defer_hash[DFR_HASHSIZE]; > +static struct hlist_head cache_defer_hash[DFR_HASHSIZE_MAX]; > static int cache_defer_cnt; > > static void __unhash_deferred_req(struct cache_deferred_req *dreq) > diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c > index 0be0dcb07f7b6..1cf9f583358af 100644 > --- a/net/unix/af_unix.c > +++ b/net/unix/af_unix.c > @@ -2024,7 +2024,7 @@ static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg, > MAX_SKB_FRAGS * PAGE_SIZE); > data_len = PAGE_ALIGN(data_len); > > - BUILD_BUG_ON(SKB_MAX_ALLOC < PAGE_SIZE); > + BUG_ON(SKB_MAX_ALLOC < PAGE_SIZE); > } > > skb = sock_alloc_send_pskb(sk, len - data_len, data_len,
