lkml.org 
[lkml]   [2021]   [Mar]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH bpf-next v2] bpf: Simplify expression for identify bpf mem type
Date
Added BPF_LD_ST_SIZE_MASK macro as mask of size modifier that help to
reduce the evaluation of expressions in if statements,
and remove BPF_SIZE_MASK in netronome driver.

Signed-off-by: Jianlin Lv <Jianlin.Lv@arm.com>
---
v2: Move the bpf_LD_ST_SIZE_MASK macro definition to include/linux/bpf.h
---
drivers/net/ethernet/netronome/nfp/bpf/main.h | 8 +++-----
include/linux/bpf.h | 1 +
kernel/bpf/verifier.c | 12 ++++--------
3 files changed, 8 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.h b/drivers/net/ethernet/netronome/nfp/bpf/main.h
index d0e17eebddd9..e90981e69763 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/main.h
+++ b/drivers/net/ethernet/netronome/nfp/bpf/main.h
@@ -346,8 +346,6 @@ struct nfp_insn_meta {
struct list_head l;
};

-#define BPF_SIZE_MASK 0x18
-
static inline u8 mbpf_class(const struct nfp_insn_meta *meta)
{
return BPF_CLASS(meta->insn.code);
@@ -375,7 +373,7 @@ static inline bool is_mbpf_alu(const struct nfp_insn_meta *meta)

static inline bool is_mbpf_load(const struct nfp_insn_meta *meta)
{
- return (meta->insn.code & ~BPF_SIZE_MASK) == (BPF_LDX | BPF_MEM);
+ return (meta->insn.code & ~BPF_LD_ST_SIZE_MASK) == (BPF_LDX | BPF_MEM);
}

static inline bool is_mbpf_jmp32(const struct nfp_insn_meta *meta)
@@ -395,7 +393,7 @@ static inline bool is_mbpf_jmp(const struct nfp_insn_meta *meta)

static inline bool is_mbpf_store(const struct nfp_insn_meta *meta)
{
- return (meta->insn.code & ~BPF_SIZE_MASK) == (BPF_STX | BPF_MEM);
+ return (meta->insn.code & ~BPF_LD_ST_SIZE_MASK) == (BPF_STX | BPF_MEM);
}

static inline bool is_mbpf_load_pkt(const struct nfp_insn_meta *meta)
@@ -430,7 +428,7 @@ static inline bool is_mbpf_classic_store_pkt(const struct nfp_insn_meta *meta)

static inline bool is_mbpf_atomic(const struct nfp_insn_meta *meta)
{
- return (meta->insn.code & ~BPF_SIZE_MASK) == (BPF_STX | BPF_ATOMIC);
+ return (meta->insn.code & ~BPF_LD_ST_SIZE_MASK) == (BPF_STX | BPF_ATOMIC);
}

static inline bool is_mbpf_mul(const struct nfp_insn_meta *meta)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index a25730eaa148..e85924719c65 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -995,6 +995,7 @@ struct bpf_array {
BPF_F_RDONLY_PROG | \
BPF_F_WRONLY | \
BPF_F_WRONLY_PROG)
+#define BPF_LD_ST_SIZE_MASK 0x18 /* mask of size modifier */

#define BPF_MAP_CAN_READ BIT(0)
#define BPF_MAP_CAN_WRITE BIT(1)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index f9096b049cd6..29fdfdb8abfa 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -11384,15 +11384,11 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
for (i = 0; i < insn_cnt; i++, insn++) {
bpf_convert_ctx_access_t convert_ctx_access;

- if (insn->code == (BPF_LDX | BPF_MEM | BPF_B) ||
- insn->code == (BPF_LDX | BPF_MEM | BPF_H) ||
- insn->code == (BPF_LDX | BPF_MEM | BPF_W) ||
- insn->code == (BPF_LDX | BPF_MEM | BPF_DW))
+ /* opcode: BPF_MEM | <size> | BPF_LDX */
+ if ((insn->code & ~BPF_LD_ST_SIZE_MASK) == (BPF_LDX | BPF_MEM))
type = BPF_READ;
- else if (insn->code == (BPF_STX | BPF_MEM | BPF_B) ||
- insn->code == (BPF_STX | BPF_MEM | BPF_H) ||
- insn->code == (BPF_STX | BPF_MEM | BPF_W) ||
- insn->code == (BPF_STX | BPF_MEM | BPF_DW))
+ /* opcode: BPF_MEM | <size> | BPF_STX */
+ else if ((insn->code & ~BPF_LD_ST_SIZE_MASK) == (BPF_STX | BPF_MEM))
type = BPF_WRITE;
else
continue;
--
2.25.1
\
 
 \ /
  Last update: 2021-03-18 07:38    [W:0.802 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site