From 163ab96b52ae2bb2d8f188cd29f0b570610f9007 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Sun, 6 Oct 2019 21:09:27 -0700 Subject: [PATCH] net: sockmap: use bitmap for copy info Don't use bool array in struct sk_msg_sg, save 12 bytes. Signed-off-by: Jakub Kicinski Reviewed-by: Dirk van der Merwe Signed-off-by: David S. Miller --- include/linux/skmsg.h | 12 ++++++++---- net/core/filter.c | 4 ++-- 2 files changed, 10 insertions(+), 6 deletions(-) diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h index e4b3fb4bb77c..fe80d537945d 100644 --- a/include/linux/skmsg.h +++ b/include/linux/skmsg.h @@ -28,13 +28,14 @@ struct sk_msg_sg { u32 end; u32 size; u32 copybreak; - bool copy[MAX_MSG_FRAGS]; + unsigned long copy; /* The extra element is used for chaining the front and sections when * the list becomes partitioned (e.g. end < start). The crypto APIs * require the chaining. */ struct scatterlist data[MAX_MSG_FRAGS + 1]; }; +static_assert(BITS_PER_LONG >= MAX_MSG_FRAGS); /* UAPI in filter.c depends on struct sk_msg_sg being first element. */ struct sk_msg { @@ -227,7 +228,7 @@ static inline void sk_msg_compute_data_pointers(struct sk_msg *msg) { struct scatterlist *sge = sk_msg_elem(msg, msg->sg.start); - if (msg->sg.copy[msg->sg.start]) { + if (test_bit(msg->sg.start, &msg->sg.copy)) { msg->data = NULL; msg->data_end = NULL; } else { @@ -246,7 +247,7 @@ static inline void sk_msg_page_add(struct sk_msg *msg, struct page *page, sg_set_page(sge, page, len, offset); sg_unmark_end(sge); - msg->sg.copy[msg->sg.end] = true; + __set_bit(msg->sg.end, &msg->sg.copy); msg->sg.size += len; sk_msg_iter_next(msg, end); } @@ -254,7 +255,10 @@ static inline void sk_msg_page_add(struct sk_msg *msg, struct page *page, static inline void sk_msg_sg_copy(struct sk_msg *msg, u32 i, bool copy_state) { do { - msg->sg.copy[i] = copy_state; + if (copy_state) + __set_bit(i, &msg->sg.copy); + else + __clear_bit(i, &msg->sg.copy); sk_msg_iter_var_next(i); if (i == msg->sg.end) break; diff --git a/net/core/filter.c b/net/core/filter.c index ed6563622ce3..46196e212413 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2245,7 +2245,7 @@ BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start, * account for the headroom. */ bytes_sg_total = start - offset + bytes; - if (!msg->sg.copy[i] && bytes_sg_total <= len) + if (!test_bit(i, &msg->sg.copy) && bytes_sg_total <= len) goto out; /* At this point we need to linearize multiple scatterlist @@ -2450,7 +2450,7 @@ BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start, /* Place newly allocated data buffer */ sk_mem_charge(msg->sk, len); msg->sg.size += len; - msg->sg.copy[new] = false; + __clear_bit(new, &msg->sg.copy); sg_set_page(&msg->sg.data[new], page, len + copy, 0); if (rsge.length) { get_page(sg_page(&rsge));