From 93aaae2e01e57483256b7da05c9a7ebd65ad4686 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 19 Nov 2010 09:49:59 -0800 Subject: filter: optimize sk_run_filter Remove pc variable to avoid arithmetic to compute fentry at each filter instruction. Jumps directly manipulate fentry pointer. As the last instruction of filter[] is guaranteed to be a RETURN, and all jumps are before the last instruction, we dont need to check filter bounds (number of instructions in filter array) at each iteration, so we remove it from sk_run_filter() params. On x86_32 remove f_k var introduced in commit 57fe93b374a6b871 (filter: make sure filters dont read uninitialized memory) Note : We could use a CONFIG_ARCH_HAS_{FEW|MANY}_REGISTERS in order to avoid too many ifdefs in this code. This helps compiler to use cpu registers to hold fentry and A accumulator. On x86_32, this saves 401 bytes, and more important, sk_run_filter() runs much faster because less register pressure (One less conditional branch per BPF instruction) # size net/core/filter.o net/core/filter_pre.o text data bss dec hex filename 2948 0 0 2948 b84 net/core/filter.o 3349 0 0 3349 d15 net/core/filter_pre.o on x86_64 : # size net/core/filter.o net/core/filter_pre.o text data bss dec hex filename 5173 0 0 5173 1435 net/core/filter.o 5224 0 0 5224 1468 net/core/filter_pre.o Signed-off-by: Eric Dumazet Acked-by: Changli Gao Signed-off-by: David S. Miller --- net/core/timestamping.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core/timestamping.c') diff --git a/net/core/timestamping.c b/net/core/timestamping.c index 0ae6c22da85b..dac7ed687f60 100644 --- a/net/core/timestamping.c +++ b/net/core/timestamping.c @@ -31,7 +31,7 @@ static unsigned int classify(struct sk_buff *skb) if (likely(skb->dev && skb->dev->phydev && skb->dev->phydev->drv)) - return sk_run_filter(skb, ptp_filter, ARRAY_SIZE(ptp_filter)); + return sk_run_filter(skb, ptp_filter); else return PTP_CLASS_NONE; } -- cgit v1.2.3 From 62ab0812137ec4f9884dd7de346238841ac03283 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 6 Dec 2010 20:50:09 +0000 Subject: filter: constify sk_run_filter() sk_run_filter() doesnt write on skb, change its prototype to reflect this. Fix two af_packet comments. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/timestamping.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core/timestamping.c') diff --git a/net/core/timestamping.c b/net/core/timestamping.c index dac7ed687f60..b124d28ff1c8 100644 --- a/net/core/timestamping.c +++ b/net/core/timestamping.c @@ -26,7 +26,7 @@ static struct sock_filter ptp_filter[] = { PTP_FILTER }; -static unsigned int classify(struct sk_buff *skb) +static unsigned int classify(const struct sk_buff *skb) { if (likely(skb->dev && skb->dev->phydev && -- cgit v1.2.3 From a19faf0250e09b16cac169354126404bc8aa342b Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 5 Dec 2010 18:50:32 +0000 Subject: net: fix skb_defer_rx_timestamp() After commit c1f19b51d1d8 (net: support time stamping in phy devices.), kernel might crash if CONFIG_NETWORK_PHY_TIMESTAMPING=y and skb_defer_rx_timestamp() handles a packet without an ethernet header. Fixes kernel bugzilla #24102 Reference: https://bugzilla.kernel.org/show_bug.cgi?id=24102 Reported-and-tested-by: Andrew Watts Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/timestamping.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'net/core/timestamping.c') diff --git a/net/core/timestamping.c b/net/core/timestamping.c index 0ae6c22da85b..c19bb4ee405e 100644 --- a/net/core/timestamping.c +++ b/net/core/timestamping.c @@ -96,11 +96,13 @@ bool skb_defer_rx_timestamp(struct sk_buff *skb) struct phy_device *phydev; unsigned int type; - skb_push(skb, ETH_HLEN); + if (skb_headroom(skb) < ETH_HLEN) + return false; + __skb_push(skb, ETH_HLEN); type = classify(skb); - skb_pull(skb, ETH_HLEN); + __skb_pull(skb, ETH_HLEN); switch (type) { case PTP_CLASS_V1_IPV4: -- cgit v1.2.3