From 78372709bf95c2ef5c886780efc268f7f052168a Mon Sep 17 00:00:00 2001 From: Michael Holzheu Date: Tue, 7 Nov 2017 19:16:25 +0100 Subject: s390/bpf: take advantage of stack_depth tracking Make use of the "stack_depth" tracking feature introduced with commit 8726679a0fa31 ("bpf: teach verifier to track stack depth") for the s390 JIT, so that stack usage can be reduced. Signed-off-by: Michael Holzheu Signed-off-by: Heiko Carstens --- arch/s390/net/bpf_jit.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'arch/s390/net/bpf_jit.h') diff --git a/arch/s390/net/bpf_jit.h b/arch/s390/net/bpf_jit.h index fda605dbc1b4..5057728b300e 100644 --- a/arch/s390/net/bpf_jit.h +++ b/arch/s390/net/bpf_jit.h @@ -52,10 +52,13 @@ extern u8 sk_load_word[], sk_load_half[], sk_load_byte[]; * * We get 160 bytes stack space from calling function, but only use * 12 * 8 byte for old backchain, r15..r6, and tail_call_cnt. + * + * The stack size used by the BPF program ("BPF stack" above) is passed + * via "aux->stack_depth". */ -#define STK_SPACE (MAX_BPF_STACK + 8 + 8 + 4 + 4 + 160) +#define STK_SPACE_ADD (8 + 8 + 4 + 4 + 160) #define STK_160_UNUSED (160 - 12 * 8) -#define STK_OFF (STK_SPACE - STK_160_UNUSED) +#define STK_OFF (STK_SPACE_ADD - STK_160_UNUSED) #define STK_OFF_TMP 160 /* Offset of tmp buffer on stack */ #define STK_OFF_HLEN 168 /* Offset of SKB header length on stack */ #define STK_OFF_SKBP 176 /* Offset of SKB pointer on stack */ -- cgit v1.2.3