From: Hou Tao <houtao1@huawei.com>
To: Alexei Starovoitov <ast@kernel.org>, Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>, Yonghong Song <yhs@fb.com>,
Daniel Borkmann <daniel@iogearbox.net>,
Andrii Nakryiko <andrii@kernel.org>,
Song Liu <songliubraving@fb.com>,
"David S . Miller" <davem@davemloft.net>,
John Fastabend <john.fastabend@gmail.com>,
<netdev@vger.kernel.org>, <bpf@vger.kernel.org>,
<houtao1@huawei.com>, Zi Shen Lim <zlim.lnx@gmail.com>,
Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will@kernel.org>,
Julien Thierry <jthierry@redhat.com>,
Ard Biesheuvel <ardb@kernel.org>,
<linux-arm-kernel@lists.infradead.org>
Subject: [PATCH bpf-next v3 2/4] arm64: insn: add encoders for atomic operations
Date: Sun, 30 Jan 2022 06:04:50 +0800 [thread overview]
Message-ID: <20220129220452.194585-3-houtao1@huawei.com> (raw)
In-Reply-To: <20220129220452.194585-1-houtao1@huawei.com>
It is a preparation patch for eBPF atomic supports under arm64. eBPF
needs support atomic[64]_fetch_add, atomic[64]_[fetch_]{and,or,xor} and
atomic[64]_{xchg|cmpxchg}. The ordering semantics of eBPF atomics are
the same with the implementations in linux kernel.
Add three helpers to support LDCLR/LDEOR/LDSET/SWP, CAS and DMB
instructions. STADD/STCLR/STEOR/STSET are simply encoded as aliases for
LDADD/LDCLR/LDEOR/LDSET with XZR as the destination register, so no extra
helper is added. atomic_fetch_add() and other atomic ops needs support for
STLXR instruction, so extend enum aarch64_insn_ldst_type to do that.
LDADD/LDEOR/LDSET/SWP and CAS instructions are only available when LSE
atomics is enabled, so just return AARCH64_BREAK_FAULT directly in
these newly-added helpers if CONFIG_ARM64_LSE_ATOMICS is disabled.
Signed-off-by: Hou Tao <houtao1@huawei.com>
---
arch/arm64/include/asm/insn.h | 80 +++++++++++++--
arch/arm64/lib/insn.c | 185 +++++++++++++++++++++++++++++++---
2 files changed, 244 insertions(+), 21 deletions(-)
diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h
index 6b776c8667b2..0b6b31307e68 100644
--- a/arch/arm64/include/asm/insn.h
+++ b/arch/arm64/include/asm/insn.h
@@ -205,7 +205,9 @@ enum aarch64_insn_ldst_type {
AARCH64_INSN_LDST_LOAD_PAIR_POST_INDEX,
AARCH64_INSN_LDST_STORE_PAIR_POST_INDEX,
AARCH64_INSN_LDST_LOAD_EX,
+ AARCH64_INSN_LDST_LOAD_ACQ_EX,
AARCH64_INSN_LDST_STORE_EX,
+ AARCH64_INSN_LDST_STORE_REL_EX,
};
enum aarch64_insn_adsb_type {
@@ -280,6 +282,36 @@ enum aarch64_insn_adr_type {
AARCH64_INSN_ADR_TYPE_ADR,
};
+enum aarch64_insn_mem_atomic_op {
+ AARCH64_INSN_MEM_ATOMIC_ADD,
+ AARCH64_INSN_MEM_ATOMIC_CLR,
+ AARCH64_INSN_MEM_ATOMIC_EOR,
+ AARCH64_INSN_MEM_ATOMIC_SET,
+ AARCH64_INSN_MEM_ATOMIC_SWP,
+};
+
+enum aarch64_insn_mem_order_type {
+ AARCH64_INSN_MEM_ORDER_NONE,
+ AARCH64_INSN_MEM_ORDER_ACQ,
+ AARCH64_INSN_MEM_ORDER_REL,
+ AARCH64_INSN_MEM_ORDER_ACQREL,
+};
+
+enum aarch64_insn_mb_type {
+ AARCH64_INSN_MB_SY,
+ AARCH64_INSN_MB_ST,
+ AARCH64_INSN_MB_LD,
+ AARCH64_INSN_MB_ISH,
+ AARCH64_INSN_MB_ISHST,
+ AARCH64_INSN_MB_ISHLD,
+ AARCH64_INSN_MB_NSH,
+ AARCH64_INSN_MB_NSHST,
+ AARCH64_INSN_MB_NSHLD,
+ AARCH64_INSN_MB_OSH,
+ AARCH64_INSN_MB_OSHST,
+ AARCH64_INSN_MB_OSHLD,
+};
+
#define __AARCH64_INSN_FUNCS(abbr, mask, val) \
static __always_inline bool aarch64_insn_is_##abbr(u32 code) \
{ \
@@ -303,6 +335,11 @@ __AARCH64_INSN_FUNCS(store_post, 0x3FE00C00, 0x38000400)
__AARCH64_INSN_FUNCS(load_post, 0x3FE00C00, 0x38400400)
__AARCH64_INSN_FUNCS(str_reg, 0x3FE0EC00, 0x38206800)
__AARCH64_INSN_FUNCS(ldadd, 0x3F20FC00, 0x38200000)
+__AARCH64_INSN_FUNCS(ldclr, 0x3F20FC00, 0x38201000)
+__AARCH64_INSN_FUNCS(ldeor, 0x3F20FC00, 0x38202000)
+__AARCH64_INSN_FUNCS(ldset, 0x3F20FC00, 0x38203000)
+__AARCH64_INSN_FUNCS(swp, 0x3F20FC00, 0x38208000)
+__AARCH64_INSN_FUNCS(cas, 0x3FA07C00, 0x08A07C00)
__AARCH64_INSN_FUNCS(ldr_reg, 0x3FE0EC00, 0x38606800)
__AARCH64_INSN_FUNCS(ldr_lit, 0xBF000000, 0x18000000)
__AARCH64_INSN_FUNCS(ldrsw_lit, 0xFF000000, 0x98000000)
@@ -474,13 +511,6 @@ u32 aarch64_insn_gen_load_store_ex(enum aarch64_insn_register reg,
enum aarch64_insn_register state,
enum aarch64_insn_size_type size,
enum aarch64_insn_ldst_type type);
-u32 aarch64_insn_gen_ldadd(enum aarch64_insn_register result,
- enum aarch64_insn_register address,
- enum aarch64_insn_register value,
- enum aarch64_insn_size_type size);
-u32 aarch64_insn_gen_stadd(enum aarch64_insn_register address,
- enum aarch64_insn_register value,
- enum aarch64_insn_size_type size);
u32 aarch64_insn_gen_add_sub_imm(enum aarch64_insn_register dst,
enum aarch64_insn_register src,
int imm, enum aarch64_insn_variant variant,
@@ -541,6 +571,42 @@ u32 aarch64_insn_gen_prefetch(enum aarch64_insn_register base,
enum aarch64_insn_prfm_type type,
enum aarch64_insn_prfm_target target,
enum aarch64_insn_prfm_policy policy);
+#ifdef CONFIG_ARM64_LSE_ATOMICS
+u32 aarch64_insn_gen_atomic_ld_op(enum aarch64_insn_register result,
+ enum aarch64_insn_register address,
+ enum aarch64_insn_register value,
+ enum aarch64_insn_size_type size,
+ enum aarch64_insn_mem_atomic_op op,
+ enum aarch64_insn_mem_order_type order);
+u32 aarch64_insn_gen_cas(enum aarch64_insn_register result,
+ enum aarch64_insn_register address,
+ enum aarch64_insn_register value,
+ enum aarch64_insn_size_type size,
+ enum aarch64_insn_mem_order_type order);
+#else
+static inline
+u32 aarch64_insn_gen_atomic_ld_op(enum aarch64_insn_register result,
+ enum aarch64_insn_register address,
+ enum aarch64_insn_register value,
+ enum aarch64_insn_size_type size,
+ enum aarch64_insn_mem_atomic_op op,
+ enum aarch64_insn_mem_order_type order)
+{
+ return AARCH64_BREAK_FAULT;
+}
+
+static inline
+u32 aarch64_insn_gen_cas(enum aarch64_insn_register result,
+ enum aarch64_insn_register address,
+ enum aarch64_insn_register value,
+ enum aarch64_insn_size_type size,
+ enum aarch64_insn_mem_order_type order)
+{
+ return AARCH64_BREAK_FAULT;
+}
+#endif
+u32 aarch64_insn_gen_dmb(enum aarch64_insn_mb_type type);
+
s32 aarch64_get_branch_offset(u32 insn);
u32 aarch64_set_branch_offset(u32 insn, s32 offset);
diff --git a/arch/arm64/lib/insn.c b/arch/arm64/lib/insn.c
index fccfe363e567..bd119fde8504 100644
--- a/arch/arm64/lib/insn.c
+++ b/arch/arm64/lib/insn.c
@@ -578,10 +578,16 @@ u32 aarch64_insn_gen_load_store_ex(enum aarch64_insn_register reg,
switch (type) {
case AARCH64_INSN_LDST_LOAD_EX:
+ case AARCH64_INSN_LDST_LOAD_ACQ_EX:
insn = aarch64_insn_get_load_ex_value();
+ if (type == AARCH64_INSN_LDST_LOAD_ACQ_EX)
+ insn |= BIT(15);
break;
case AARCH64_INSN_LDST_STORE_EX:
+ case AARCH64_INSN_LDST_STORE_REL_EX:
insn = aarch64_insn_get_store_ex_value();
+ if (type == AARCH64_INSN_LDST_STORE_REL_EX)
+ insn |= BIT(15);
break;
default:
pr_err("%s: unknown load/store exclusive encoding %d\n", __func__, type);
@@ -603,12 +609,65 @@ u32 aarch64_insn_gen_load_store_ex(enum aarch64_insn_register reg,
state);
}
-u32 aarch64_insn_gen_ldadd(enum aarch64_insn_register result,
- enum aarch64_insn_register address,
- enum aarch64_insn_register value,
- enum aarch64_insn_size_type size)
+#ifdef CONFIG_ARM64_LSE_ATOMICS
+static u32 aarch64_insn_encode_ldst_order(enum aarch64_insn_mem_order_type type,
+ u32 insn)
{
- u32 insn = aarch64_insn_get_ldadd_value();
+ u32 order;
+
+ switch (type) {
+ case AARCH64_INSN_MEM_ORDER_NONE:
+ order = 0;
+ break;
+ case AARCH64_INSN_MEM_ORDER_ACQ:
+ order = 2;
+ break;
+ case AARCH64_INSN_MEM_ORDER_REL:
+ order = 1;
+ break;
+ case AARCH64_INSN_MEM_ORDER_ACQREL:
+ order = 3;
+ break;
+ default:
+ pr_err("%s: unknown mem order %d\n", __func__, type);
+ return AARCH64_BREAK_FAULT;
+ }
+
+ insn &= ~GENMASK(23, 22);
+ insn |= order << 22;
+
+ return insn;
+}
+
+u32 aarch64_insn_gen_atomic_ld_op(enum aarch64_insn_register result,
+ enum aarch64_insn_register address,
+ enum aarch64_insn_register value,
+ enum aarch64_insn_size_type size,
+ enum aarch64_insn_mem_atomic_op op,
+ enum aarch64_insn_mem_order_type order)
+{
+ u32 insn;
+
+ switch (op) {
+ case AARCH64_INSN_MEM_ATOMIC_ADD:
+ insn = aarch64_insn_get_ldadd_value();
+ break;
+ case AARCH64_INSN_MEM_ATOMIC_CLR:
+ insn = aarch64_insn_get_ldclr_value();
+ break;
+ case AARCH64_INSN_MEM_ATOMIC_EOR:
+ insn = aarch64_insn_get_ldeor_value();
+ break;
+ case AARCH64_INSN_MEM_ATOMIC_SET:
+ insn = aarch64_insn_get_ldset_value();
+ break;
+ case AARCH64_INSN_MEM_ATOMIC_SWP:
+ insn = aarch64_insn_get_swp_value();
+ break;
+ default:
+ pr_err("%s: unimplemented mem atomic op %d\n", __func__, op);
+ return AARCH64_BREAK_FAULT;
+ }
switch (size) {
case AARCH64_INSN_SIZE_32:
@@ -621,6 +680,8 @@ u32 aarch64_insn_gen_ldadd(enum aarch64_insn_register result,
insn = aarch64_insn_encode_ldst_size(size, insn);
+ insn = aarch64_insn_encode_ldst_order(order, insn);
+
insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn,
result);
@@ -631,17 +692,68 @@ u32 aarch64_insn_gen_ldadd(enum aarch64_insn_register result,
value);
}
-u32 aarch64_insn_gen_stadd(enum aarch64_insn_register address,
- enum aarch64_insn_register value,
- enum aarch64_insn_size_type size)
+static u32 aarch64_insn_encode_cas_order(enum aarch64_insn_mem_order_type type,
+ u32 insn)
{
- /*
- * STADD is simply encoded as an alias for LDADD with XZR as
- * the destination register.
- */
- return aarch64_insn_gen_ldadd(AARCH64_INSN_REG_ZR, address,
- value, size);
+ u32 order;
+
+ switch (type) {
+ case AARCH64_INSN_MEM_ORDER_NONE:
+ order = 0;
+ break;
+ case AARCH64_INSN_MEM_ORDER_ACQ:
+ order = BIT(22);
+ break;
+ case AARCH64_INSN_MEM_ORDER_REL:
+ order = BIT(15);
+ break;
+ case AARCH64_INSN_MEM_ORDER_ACQREL:
+ order = BIT(15) | BIT(22);
+ break;
+ default:
+ pr_err("%s: unknown mem order %d\n", __func__, type);
+ return AARCH64_BREAK_FAULT;
+ }
+
+ insn &= ~(BIT(15) | BIT(22));
+ insn |= order;
+
+ return insn;
+}
+
+u32 aarch64_insn_gen_cas(enum aarch64_insn_register result,
+ enum aarch64_insn_register address,
+ enum aarch64_insn_register value,
+ enum aarch64_insn_size_type size,
+ enum aarch64_insn_mem_order_type order)
+{
+ u32 insn;
+
+ switch (size) {
+ case AARCH64_INSN_SIZE_32:
+ case AARCH64_INSN_SIZE_64:
+ break;
+ default:
+ pr_err("%s: unimplemented size encoding %d\n", __func__, size);
+ return AARCH64_BREAK_FAULT;
+ }
+
+ insn = aarch64_insn_get_cas_value();
+
+ insn = aarch64_insn_encode_ldst_size(size, insn);
+
+ insn = aarch64_insn_encode_cas_order(order, insn);
+
+ insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn,
+ result);
+
+ insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn,
+ address);
+
+ return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RS, insn,
+ value);
}
+#endif
static u32 aarch64_insn_encode_prfm_imm(enum aarch64_insn_prfm_type type,
enum aarch64_insn_prfm_target target,
@@ -1456,3 +1568,48 @@ u32 aarch64_insn_gen_extr(enum aarch64_insn_variant variant,
insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, Rn);
return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RM, insn, Rm);
}
+
+u32 aarch64_insn_gen_dmb(enum aarch64_insn_mb_type type)
+{
+ u32 opt;
+ u32 insn;
+
+ switch (type) {
+ case AARCH64_INSN_MB_SY:
+ opt = 0xf;
+ break;
+ case AARCH64_INSN_MB_ST:
+ opt = 0xe;
+ break;
+ case AARCH64_INSN_MB_LD:
+ opt = 0xd;
+ break;
+ case AARCH64_INSN_MB_ISH:
+ opt = 0xb;
+ break;
+ case AARCH64_INSN_MB_ISHST:
+ opt = 0xa;
+ break;
+ case AARCH64_INSN_MB_ISHLD:
+ opt = 0x9;
+ break;
+ case AARCH64_INSN_MB_NSH:
+ opt = 0x7;
+ break;
+ case AARCH64_INSN_MB_NSHST:
+ opt = 0x6;
+ break;
+ case AARCH64_INSN_MB_NSHLD:
+ opt = 0x5;
+ break;
+ default:
+ pr_err("%s: unknown dmb type %d\n", __func__, type);
+ return AARCH64_BREAK_FAULT;
+ }
+
+ insn = aarch64_insn_get_dmb_value();
+ insn &= ~GENMASK(11, 8);
+ insn |= (opt << 8);
+
+ return insn;
+}
--
2.27.0
next prev parent reply other threads:[~2022-02-07 14:18 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-29 22:04 [PATCH bpf-next v3 0/4] bpf, arm64: support more atomic ops Hou Tao
2022-01-29 22:04 ` [PATCH bpf-next v3 1/4] arm64: move AARCH64_BREAK_FAULT into insn-def.h Hou Tao
2022-01-29 22:04 ` Hou Tao [this message]
2022-02-11 14:39 ` [PATCH bpf-next v3 2/4] arm64: insn: add encoders for atomic operations Daniel Borkmann
2022-02-15 17:42 ` Will Deacon
2022-02-16 0:21 ` Daniel Borkmann
2022-02-16 17:16 ` Will Deacon
2022-02-17 1:55 ` Hou Tao
2022-01-29 22:04 ` [PATCH bpf-next v3 3/4] bpf, arm64: support more " Hou Tao
2022-01-29 22:04 ` [PATCH bpf-next v3 4/4] selftests/bpf: use raw_tp program for atomic test Hou Tao
2022-02-15 4:25 ` [PATCH bpf-next v3 0/4] bpf, arm64: support more atomic ops Hou Tao
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220129220452.194585-3-houtao1@huawei.com \
--to=houtao1@huawei.com \
--cc=andrii@kernel.org \
--cc=ardb@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=catalin.marinas@arm.com \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=john.fastabend@gmail.com \
--cc=jthierry@redhat.com \
--cc=kafai@fb.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=mark.rutland@arm.com \
--cc=netdev@vger.kernel.org \
--cc=songliubraving@fb.com \
--cc=will@kernel.org \
--cc=yhs@fb.com \
--cc=zlim.lnx@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).