* [PATCH V7 1/2] riscv: Add support for perf registers sampling
2019-09-05 3:46 [PATCH V7 0/2] riscv: Add perf callchain support Mao Han
@ 2019-09-05 3:46 ` Mao Han
2019-09-05 7:54 ` Paul Walmsley
2019-09-05 3:46 ` [PATCH V7 2/2] riscv: Add support for libdw Mao Han
1 sibling, 1 reply; 5+ messages in thread
From: Mao Han @ 2019-09-05 3:46 UTC (permalink / raw)
To: linux-riscv
Cc: linux-kernel, linux-csky, Mao Han, Paul Walmsley, Greentime Hu,
Palmer Dabbelt, Christoph Hellwig, Guo Ren
This patch implements the perf registers sampling and validation API
for riscv arch. The valid registers and their register ID are defined in
perf_regs.h. Perf tool can backtrace in userspace with unwind library
and the registers/user stack dump support.
Signed-off-by: Mao Han <han_mao@c-sky.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: linux-riscv <linux-riscv@lists.infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Guo Ren <guoren@kernel.org>
---
arch/riscv/Kconfig | 2 ++
arch/riscv/include/uapi/asm/perf_regs.h | 42 +++++++++++++++++++++++++++++++
arch/riscv/kernel/Makefile | 1 +
arch/riscv/kernel/perf_regs.c | 44 +++++++++++++++++++++++++++++++++
4 files changed, 89 insertions(+)
create mode 100644 arch/riscv/include/uapi/asm/perf_regs.h
create mode 100644 arch/riscv/kernel/perf_regs.c
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 59a4727..4bc976d 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -35,6 +35,8 @@ config RISCV
select HAVE_DMA_CONTIGUOUS
select HAVE_FUTEX_CMPXCHG if FUTEX
select HAVE_PERF_EVENTS
+ select HAVE_PERF_REGS
+ select HAVE_PERF_USER_STACK_DUMP
select HAVE_SYSCALL_TRACEPOINTS
select IRQ_DOMAIN
select SPARSE_IRQ
diff --git a/arch/riscv/include/uapi/asm/perf_regs.h b/arch/riscv/include/uapi/asm/perf_regs.h
new file mode 100644
index 0000000..196f964
--- /dev/null
+++ b/arch/riscv/include/uapi/asm/perf_regs.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd. */
+
+#ifndef _ASM_RISCV_PERF_REGS_H
+#define _ASM_RISCV_PERF_REGS_H
+
+enum perf_event_riscv_regs {
+ PERF_REG_RISCV_PC,
+ PERF_REG_RISCV_RA,
+ PERF_REG_RISCV_SP,
+ PERF_REG_RISCV_GP,
+ PERF_REG_RISCV_TP,
+ PERF_REG_RISCV_T0,
+ PERF_REG_RISCV_T1,
+ PERF_REG_RISCV_T2,
+ PERF_REG_RISCV_S0,
+ PERF_REG_RISCV_S1,
+ PERF_REG_RISCV_A0,
+ PERF_REG_RISCV_A1,
+ PERF_REG_RISCV_A2,
+ PERF_REG_RISCV_A3,
+ PERF_REG_RISCV_A4,
+ PERF_REG_RISCV_A5,
+ PERF_REG_RISCV_A6,
+ PERF_REG_RISCV_A7,
+ PERF_REG_RISCV_S2,
+ PERF_REG_RISCV_S3,
+ PERF_REG_RISCV_S4,
+ PERF_REG_RISCV_S5,
+ PERF_REG_RISCV_S6,
+ PERF_REG_RISCV_S7,
+ PERF_REG_RISCV_S8,
+ PERF_REG_RISCV_S9,
+ PERF_REG_RISCV_S10,
+ PERF_REG_RISCV_S11,
+ PERF_REG_RISCV_T3,
+ PERF_REG_RISCV_T4,
+ PERF_REG_RISCV_T5,
+ PERF_REG_RISCV_T6,
+ PERF_REG_RISCV_MAX,
+};
+#endif /* _ASM_RISCV_PERF_REGS_H */
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index b1bea89..696020f 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -40,5 +40,6 @@ obj-$(CONFIG_DYNAMIC_FTRACE) += mcount-dyn.o
obj-$(CONFIG_PERF_EVENTS) += perf_event.o
obj-$(CONFIG_PERF_EVENTS) += perf_callchain.o
+obj-$(CONFIG_HAVE_PERF_REGS) += perf_regs.o
clean:
diff --git a/arch/riscv/kernel/perf_regs.c b/arch/riscv/kernel/perf_regs.c
new file mode 100644
index 0000000..04a38fb
--- /dev/null
+++ b/arch/riscv/kernel/perf_regs.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd. */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/perf_event.h>
+#include <linux/bug.h>
+#include <asm/perf_regs.h>
+#include <asm/ptrace.h>
+
+u64 perf_reg_value(struct pt_regs *regs, int idx)
+{
+ if (WARN_ON_ONCE((u32)idx >= PERF_REG_RISCV_MAX))
+ return 0;
+
+ return ((unsigned long *)regs)[idx];
+}
+
+#define REG_RESERVED (~((1ULL << PERF_REG_RISCV_MAX) - 1))
+
+int perf_reg_validate(u64 mask)
+{
+ if (!mask || mask & REG_RESERVED)
+ return -EINVAL;
+
+ return 0;
+}
+
+u64 perf_reg_abi(struct task_struct *task)
+{
+#if __riscv_xlen == 64
+ return PERF_SAMPLE_REGS_ABI_64;
+#else
+ return PERF_SAMPLE_REGS_ABI_32;
+#endif
+}
+
+void perf_get_regs_user(struct perf_regs *regs_user,
+ struct pt_regs *regs,
+ struct pt_regs *regs_user_copy)
+{
+ regs_user->regs = task_pt_regs(current);
+ regs_user->abi = perf_reg_abi(current);
+}
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH V7 2/2] riscv: Add support for libdw
2019-09-05 3:46 [PATCH V7 0/2] riscv: Add perf callchain support Mao Han
2019-09-05 3:46 ` [PATCH V7 1/2] riscv: Add support for perf registers sampling Mao Han
@ 2019-09-05 3:46 ` Mao Han
2019-09-05 7:55 ` Paul Walmsley
1 sibling, 1 reply; 5+ messages in thread
From: Mao Han @ 2019-09-05 3:46 UTC (permalink / raw)
To: linux-riscv
Cc: linux-kernel, linux-csky, Mao Han, Paul Walmsley, Greentime Hu,
Palmer Dabbelt, Christoph Hellwig, Guo Ren
This patch adds support for DWARF register mappings and libdw registers
initialization, which is used by perf callchain analyzing when
--call-graph=dwarf is given.
Signed-off-by: Mao Han <han_mao@c-sky.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: linux-riscv <linux-riscv@lists.infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Guo Ren <guoren@kernel.org>
---
tools/arch/riscv/include/uapi/asm/perf_regs.h | 42 ++++++++++++
tools/perf/Makefile.config | 6 +-
tools/perf/arch/riscv/Build | 1 +
tools/perf/arch/riscv/Makefile | 4 ++
tools/perf/arch/riscv/include/perf_regs.h | 96 +++++++++++++++++++++++++++
tools/perf/arch/riscv/util/Build | 2 +
tools/perf/arch/riscv/util/dwarf-regs.c | 72 ++++++++++++++++++++
tools/perf/arch/riscv/util/unwind-libdw.c | 57 ++++++++++++++++
8 files changed, 279 insertions(+), 1 deletion(-)
create mode 100644 tools/arch/riscv/include/uapi/asm/perf_regs.h
create mode 100644 tools/perf/arch/riscv/Build
create mode 100644 tools/perf/arch/riscv/Makefile
create mode 100644 tools/perf/arch/riscv/include/perf_regs.h
create mode 100644 tools/perf/arch/riscv/util/Build
create mode 100644 tools/perf/arch/riscv/util/dwarf-regs.c
create mode 100644 tools/perf/arch/riscv/util/unwind-libdw.c
diff --git a/tools/arch/riscv/include/uapi/asm/perf_regs.h b/tools/arch/riscv/include/uapi/asm/perf_regs.h
new file mode 100644
index 0000000..196f964
--- /dev/null
+++ b/tools/arch/riscv/include/uapi/asm/perf_regs.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd. */
+
+#ifndef _ASM_RISCV_PERF_REGS_H
+#define _ASM_RISCV_PERF_REGS_H
+
+enum perf_event_riscv_regs {
+ PERF_REG_RISCV_PC,
+ PERF_REG_RISCV_RA,
+ PERF_REG_RISCV_SP,
+ PERF_REG_RISCV_GP,
+ PERF_REG_RISCV_TP,
+ PERF_REG_RISCV_T0,
+ PERF_REG_RISCV_T1,
+ PERF_REG_RISCV_T2,
+ PERF_REG_RISCV_S0,
+ PERF_REG_RISCV_S1,
+ PERF_REG_RISCV_A0,
+ PERF_REG_RISCV_A1,
+ PERF_REG_RISCV_A2,
+ PERF_REG_RISCV_A3,
+ PERF_REG_RISCV_A4,
+ PERF_REG_RISCV_A5,
+ PERF_REG_RISCV_A6,
+ PERF_REG_RISCV_A7,
+ PERF_REG_RISCV_S2,
+ PERF_REG_RISCV_S3,
+ PERF_REG_RISCV_S4,
+ PERF_REG_RISCV_S5,
+ PERF_REG_RISCV_S6,
+ PERF_REG_RISCV_S7,
+ PERF_REG_RISCV_S8,
+ PERF_REG_RISCV_S9,
+ PERF_REG_RISCV_S10,
+ PERF_REG_RISCV_S11,
+ PERF_REG_RISCV_T3,
+ PERF_REG_RISCV_T4,
+ PERF_REG_RISCV_T5,
+ PERF_REG_RISCV_T6,
+ PERF_REG_RISCV_MAX,
+};
+#endif /* _ASM_RISCV_PERF_REGS_H */
diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index 89ac5a1..eaf25ee 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -60,6 +60,10 @@ ifeq ($(SRCARCH),arm64)
LIBUNWIND_LIBS = -lunwind -lunwind-aarch64
endif
+ifeq ($(SRCARCH),riscv)
+ NO_PERF_REGS := 0
+endif
+
ifeq ($(SRCARCH),csky)
NO_PERF_REGS := 0
endif
@@ -82,7 +86,7 @@ endif
# Disable it on all other architectures in case libdw unwind
# support is detected in system. Add supported architectures
# to the check.
-ifneq ($(SRCARCH),$(filter $(SRCARCH),x86 arm arm64 powerpc s390 csky))
+ifneq ($(SRCARCH),$(filter $(SRCARCH),x86 arm arm64 powerpc s390 csky riscv))
NO_LIBDW_DWARF_UNWIND := 1
endif
diff --git a/tools/perf/arch/riscv/Build b/tools/perf/arch/riscv/Build
new file mode 100644
index 0000000..e4e5f33
--- /dev/null
+++ b/tools/perf/arch/riscv/Build
@@ -0,0 +1 @@
+perf-y += util/
diff --git a/tools/perf/arch/riscv/Makefile b/tools/perf/arch/riscv/Makefile
new file mode 100644
index 0000000..1aa9dd7
--- /dev/null
+++ b/tools/perf/arch/riscv/Makefile
@@ -0,0 +1,4 @@
+ifndef NO_DWARF
+PERF_HAVE_DWARF_REGS := 1
+endif
+PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET := 1
diff --git a/tools/perf/arch/riscv/include/perf_regs.h b/tools/perf/arch/riscv/include/perf_regs.h
new file mode 100644
index 0000000..7a8bcde
--- /dev/null
+++ b/tools/perf/arch/riscv/include/perf_regs.h
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd. */
+
+#ifndef ARCH_PERF_REGS_H
+#define ARCH_PERF_REGS_H
+
+#include <stdlib.h>
+#include <linux/types.h>
+#include <asm/perf_regs.h>
+
+#define PERF_REGS_MASK ((1ULL << PERF_REG_RISCV_MAX) - 1)
+#define PERF_REGS_MAX PERF_REG_RISCV_MAX
+#if __riscv_xlen == 64
+#define PERF_SAMPLE_REGS_ABI PERF_SAMPLE_REGS_ABI_64
+#else
+#define PERF_SAMPLE_REGS_ABI PERF_SAMPLE_REGS_ABI_32
+#endif
+
+#define PERF_REG_IP PERF_REG_RISCV_PC
+#define PERF_REG_SP PERF_REG_RISCV_SP
+
+static inline const char *perf_reg_name(int id)
+{
+ switch (id) {
+ case PERF_REG_RISCV_PC:
+ return "pc";
+ case PERF_REG_RISCV_RA:
+ return "ra";
+ case PERF_REG_RISCV_SP:
+ return "sp";
+ case PERF_REG_RISCV_GP:
+ return "gp";
+ case PERF_REG_RISCV_TP:
+ return "tp";
+ case PERF_REG_RISCV_T0:
+ return "t0";
+ case PERF_REG_RISCV_T1:
+ return "t1";
+ case PERF_REG_RISCV_T2:
+ return "t2";
+ case PERF_REG_RISCV_S0:
+ return "s0";
+ case PERF_REG_RISCV_S1:
+ return "s1";
+ case PERF_REG_RISCV_A0:
+ return "a0";
+ case PERF_REG_RISCV_A1:
+ return "a1";
+ case PERF_REG_RISCV_A2:
+ return "a2";
+ case PERF_REG_RISCV_A3:
+ return "a3";
+ case PERF_REG_RISCV_A4:
+ return "a4";
+ case PERF_REG_RISCV_A5:
+ return "a5";
+ case PERF_REG_RISCV_A6:
+ return "a6";
+ case PERF_REG_RISCV_A7:
+ return "a7";
+ case PERF_REG_RISCV_S2:
+ return "s2";
+ case PERF_REG_RISCV_S3:
+ return "s3";
+ case PERF_REG_RISCV_S4:
+ return "s4";
+ case PERF_REG_RISCV_S5:
+ return "s5";
+ case PERF_REG_RISCV_S6:
+ return "s6";
+ case PERF_REG_RISCV_S7:
+ return "s7";
+ case PERF_REG_RISCV_S8:
+ return "s8";
+ case PERF_REG_RISCV_S9:
+ return "s9";
+ case PERF_REG_RISCV_S10:
+ return "s10";
+ case PERF_REG_RISCV_S11:
+ return "s11";
+ case PERF_REG_RISCV_T3:
+ return "t3";
+ case PERF_REG_RISCV_T4:
+ return "t4";
+ case PERF_REG_RISCV_T5:
+ return "t5";
+ case PERF_REG_RISCV_T6:
+ return "t6";
+ default:
+ return NULL;
+ }
+
+ return NULL;
+}
+
+#endif /* ARCH_PERF_REGS_H */
diff --git a/tools/perf/arch/riscv/util/Build b/tools/perf/arch/riscv/util/Build
new file mode 100644
index 0000000..1160bb2
--- /dev/null
+++ b/tools/perf/arch/riscv/util/Build
@@ -0,0 +1,2 @@
+perf-$(CONFIG_DWARF) += dwarf-regs.o
+perf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
diff --git a/tools/perf/arch/riscv/util/dwarf-regs.c b/tools/perf/arch/riscv/util/dwarf-regs.c
new file mode 100644
index 0000000..cd0504c
--- /dev/null
+++ b/tools/perf/arch/riscv/util/dwarf-regs.c
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd.
+ * Mapping of DWARF debug register numbers into register names.
+ */
+
+#include <stddef.h>
+#include <errno.h> /* for EINVAL */
+#include <string.h> /* for strcmp */
+#include <dwarf-regs.h>
+
+struct pt_regs_dwarfnum {
+ const char *name;
+ unsigned int dwarfnum;
+};
+
+#define REG_DWARFNUM_NAME(r, num) {.name = r, .dwarfnum = num}
+#define REG_DWARFNUM_END {.name = NULL, .dwarfnum = 0}
+
+struct pt_regs_dwarfnum riscv_dwarf_regs_table[] = {
+ REG_DWARFNUM_NAME("%zero", 0),
+ REG_DWARFNUM_NAME("%ra", 1),
+ REG_DWARFNUM_NAME("%sp", 2),
+ REG_DWARFNUM_NAME("%gp", 3),
+ REG_DWARFNUM_NAME("%tp", 4),
+ REG_DWARFNUM_NAME("%t0", 5),
+ REG_DWARFNUM_NAME("%t1", 6),
+ REG_DWARFNUM_NAME("%t2", 7),
+ REG_DWARFNUM_NAME("%s0", 8),
+ REG_DWARFNUM_NAME("%s1", 9),
+ REG_DWARFNUM_NAME("%a0", 10),
+ REG_DWARFNUM_NAME("%a1", 11),
+ REG_DWARFNUM_NAME("%a2", 12),
+ REG_DWARFNUM_NAME("%a3", 13),
+ REG_DWARFNUM_NAME("%a4", 14),
+ REG_DWARFNUM_NAME("%a5", 15),
+ REG_DWARFNUM_NAME("%a6", 16),
+ REG_DWARFNUM_NAME("%a7", 17),
+ REG_DWARFNUM_NAME("%s2", 18),
+ REG_DWARFNUM_NAME("%s3", 19),
+ REG_DWARFNUM_NAME("%s4", 20),
+ REG_DWARFNUM_NAME("%s5", 21),
+ REG_DWARFNUM_NAME("%s6", 22),
+ REG_DWARFNUM_NAME("%s7", 23),
+ REG_DWARFNUM_NAME("%s8", 24),
+ REG_DWARFNUM_NAME("%s9", 25),
+ REG_DWARFNUM_NAME("%s10", 26),
+ REG_DWARFNUM_NAME("%s11", 27),
+ REG_DWARFNUM_NAME("%t3", 28),
+ REG_DWARFNUM_NAME("%t4", 29),
+ REG_DWARFNUM_NAME("%t5", 30),
+ REG_DWARFNUM_NAME("%t6", 31),
+ REG_DWARFNUM_END,
+};
+
+#define RISCV_MAX_REGS ((sizeof(riscv_dwarf_regs_table) / \
+ sizeof(riscv_dwarf_regs_table[0])) - 1)
+
+const char *get_arch_regstr(unsigned int n)
+{
+ return (n < RISCV_MAX_REGS) ? riscv_dwarf_regs_table[n].name : NULL;
+}
+
+int regs_query_register_offset(const char *name)
+{
+ const struct pt_regs_dwarfnum *roff;
+
+ for (roff = riscv_dwarf_regs_table; roff->name; roff++)
+ if (!strcmp(roff->name, name))
+ return roff->dwarfnum;
+ return -EINVAL;
+}
diff --git a/tools/perf/arch/riscv/util/unwind-libdw.c b/tools/perf/arch/riscv/util/unwind-libdw.c
new file mode 100644
index 0000000..19536e1
--- /dev/null
+++ b/tools/perf/arch/riscv/util/unwind-libdw.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd. */
+
+#include <elfutils/libdwfl.h>
+#include "../../util/unwind-libdw.h"
+#include "../../util/perf_regs.h"
+#include "../../util/event.h"
+
+bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
+{
+ struct unwind_info *ui = arg;
+ struct regs_dump *user_regs = &ui->sample->user_regs;
+ Dwarf_Word dwarf_regs[32];
+
+#define REG(r) ({ \
+ Dwarf_Word val = 0; \
+ perf_reg_value(&val, user_regs, PERF_REG_RISCV_##r); \
+ val; \
+})
+
+ dwarf_regs[0] = 0;
+ dwarf_regs[1] = REG(RA);
+ dwarf_regs[2] = REG(SP);
+ dwarf_regs[3] = REG(GP);
+ dwarf_regs[4] = REG(TP);
+ dwarf_regs[5] = REG(T0);
+ dwarf_regs[6] = REG(T1);
+ dwarf_regs[7] = REG(T2);
+ dwarf_regs[8] = REG(S0);
+ dwarf_regs[9] = REG(S1);
+ dwarf_regs[10] = REG(A0);
+ dwarf_regs[11] = REG(A1);
+ dwarf_regs[12] = REG(A2);
+ dwarf_regs[13] = REG(A3);
+ dwarf_regs[14] = REG(A4);
+ dwarf_regs[15] = REG(A5);
+ dwarf_regs[16] = REG(A6);
+ dwarf_regs[17] = REG(A7);
+ dwarf_regs[18] = REG(S2);
+ dwarf_regs[19] = REG(S3);
+ dwarf_regs[20] = REG(S4);
+ dwarf_regs[21] = REG(S5);
+ dwarf_regs[22] = REG(S6);
+ dwarf_regs[23] = REG(S7);
+ dwarf_regs[24] = REG(S8);
+ dwarf_regs[25] = REG(S9);
+ dwarf_regs[26] = REG(S10);
+ dwarf_regs[27] = REG(S11);
+ dwarf_regs[28] = REG(T3);
+ dwarf_regs[29] = REG(T4);
+ dwarf_regs[30] = REG(T5);
+ dwarf_regs[31] = REG(T6);
+ dwfl_thread_state_register_pc(thread, REG(PC));
+
+ return dwfl_thread_state_registers(thread, 0, PERF_REG_RISCV_MAX,
+ dwarf_regs);
+}
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread