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-rw-r--r--arch/riscv/kernel/Makefile4
-rw-r--r--arch/riscv/kernel/entry.S6
-rw-r--r--arch/riscv/kernel/fpu.S8
-rw-r--r--arch/riscv/kernel/head.S2
-rw-r--r--arch/riscv/kernel/perf_callchain.c94
-rw-r--r--arch/riscv/kernel/perf_regs.c44
-rw-r--r--arch/riscv/kernel/smp.c60
-rw-r--r--arch/riscv/kernel/stacktrace.c4
8 files changed, 187 insertions, 35 deletions
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index 2420d37d96de..696020ff72db 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -38,6 +38,8 @@ obj-$(CONFIG_MODULE_SECTIONS) += module-sections.o
obj-$(CONFIG_FUNCTION_TRACER) += mcount.o ftrace.o
obj-$(CONFIG_DYNAMIC_FTRACE) += mcount-dyn.o
-obj-$(CONFIG_PERF_EVENTS) += perf_event.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/entry.S b/arch/riscv/kernel/entry.S
index bc7a56e1ca6f..74ccfd464071 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -167,7 +167,7 @@ ENTRY(handle_exception)
tail do_IRQ
1:
/* Exceptions run with interrupts enabled */
- csrs sstatus, SR_SIE
+ csrs CSR_SSTATUS, SR_SIE
/* Handle syscalls */
li t0, EXC_SYSCALL
@@ -222,7 +222,7 @@ ret_from_syscall:
ret_from_exception:
REG_L s0, PT_SSTATUS(sp)
- csrc sstatus, SR_SIE
+ csrc CSR_SSTATUS, SR_SIE
andi s0, s0, SR_SPP
bnez s0, resume_kernel
@@ -265,7 +265,7 @@ work_pending:
bnez s1, work_resched
work_notifysig:
/* Handle pending signals and notify-resume requests */
- csrs sstatus, SR_SIE /* Enable interrupts for do_notify_resume() */
+ csrs CSR_SSTATUS, SR_SIE /* Enable interrupts for do_notify_resume() */
move a0, sp /* pt_regs */
move a1, s0 /* current_thread_info->flags */
tail do_notify_resume
diff --git a/arch/riscv/kernel/fpu.S b/arch/riscv/kernel/fpu.S
index 1defb0618aff..631d31540660 100644
--- a/arch/riscv/kernel/fpu.S
+++ b/arch/riscv/kernel/fpu.S
@@ -23,7 +23,7 @@ ENTRY(__fstate_save)
li a2, TASK_THREAD_F0
add a0, a0, a2
li t1, SR_FS
- csrs sstatus, t1
+ csrs CSR_SSTATUS, t1
frcsr t0
fsd f0, TASK_THREAD_F0_F0(a0)
fsd f1, TASK_THREAD_F1_F0(a0)
@@ -58,7 +58,7 @@ ENTRY(__fstate_save)
fsd f30, TASK_THREAD_F30_F0(a0)
fsd f31, TASK_THREAD_F31_F0(a0)
sw t0, TASK_THREAD_FCSR_F0(a0)
- csrc sstatus, t1
+ csrc CSR_SSTATUS, t1
ret
ENDPROC(__fstate_save)
@@ -67,7 +67,7 @@ ENTRY(__fstate_restore)
add a0, a0, a2
li t1, SR_FS
lw t0, TASK_THREAD_FCSR_F0(a0)
- csrs sstatus, t1
+ csrs CSR_SSTATUS, t1
fld f0, TASK_THREAD_F0_F0(a0)
fld f1, TASK_THREAD_F1_F0(a0)
fld f2, TASK_THREAD_F2_F0(a0)
@@ -101,6 +101,6 @@ ENTRY(__fstate_restore)
fld f30, TASK_THREAD_F30_F0(a0)
fld f31, TASK_THREAD_F31_F0(a0)
fscsr t0
- csrc sstatus, t1
+ csrc CSR_SSTATUS, t1
ret
ENDPROC(__fstate_restore)
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 52eec0c1bf30..15a9189f91ad 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -61,7 +61,7 @@ _start_kernel:
* floating point in kernel space
*/
li t0, SR_FS
- csrc sstatus, t0
+ csrc CSR_SSTATUS, t0
/* Pick one hart to run the main boot sequence */
la a3, hart_lottery
diff --git a/arch/riscv/kernel/perf_callchain.c b/arch/riscv/kernel/perf_callchain.c
new file mode 100644
index 000000000000..8d2804f05cf9
--- /dev/null
+++ b/arch/riscv/kernel/perf_callchain.c
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd. */
+
+#include <linux/perf_event.h>
+#include <linux/uaccess.h>
+
+/* Kernel callchain */
+struct stackframe {
+ unsigned long fp;
+ unsigned long ra;
+};
+
+/*
+ * Get the return address for a single stackframe and return a pointer to the
+ * next frame tail.
+ */
+static unsigned long user_backtrace(struct perf_callchain_entry_ctx *entry,
+ unsigned long fp, unsigned long reg_ra)
+{
+ struct stackframe buftail;
+ unsigned long ra = 0;
+ unsigned long *user_frame_tail =
+ (unsigned long *)(fp - sizeof(struct stackframe));
+
+ /* Check accessibility of one struct frame_tail beyond */
+ if (!access_ok(user_frame_tail, sizeof(buftail)))
+ return 0;
+ if (__copy_from_user_inatomic(&buftail, user_frame_tail,
+ sizeof(buftail)))
+ return 0;
+
+ if (reg_ra != 0)
+ ra = reg_ra;
+ else
+ ra = buftail.ra;
+
+ fp = buftail.fp;
+ if (ra != 0)
+ perf_callchain_store(entry, ra);
+ else
+ return 0;
+
+ return fp;
+}
+
+/*
+ * This will be called when the target is in user mode
+ * This function will only be called when we use
+ * "PERF_SAMPLE_CALLCHAIN" in
+ * kernel/events/core.c:perf_prepare_sample()
+ *
+ * How to trigger perf_callchain_[user/kernel] :
+ * $ perf record -e cpu-clock --call-graph fp ./program
+ * $ perf report --call-graph
+ *
+ * On RISC-V platform, the program being sampled and the C library
+ * need to be compiled with -fno-omit-frame-pointer, otherwise
+ * the user stack will not contain function frame.
+ */
+void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
+ struct pt_regs *regs)
+{
+ unsigned long fp = 0;
+
+ /* RISC-V does not support perf in guest mode. */
+ if (perf_guest_cbs && perf_guest_cbs->is_in_guest())
+ return;
+
+ fp = regs->s0;
+ perf_callchain_store(entry, regs->sepc);
+
+ fp = user_backtrace(entry, fp, regs->ra);
+ while (fp && !(fp & 0x3) && entry->nr < entry->max_stack)
+ fp = user_backtrace(entry, fp, 0);
+}
+
+bool fill_callchain(unsigned long pc, void *entry)
+{
+ return perf_callchain_store(entry, pc);
+}
+
+void notrace walk_stackframe(struct task_struct *task,
+ struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg);
+void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
+ struct pt_regs *regs)
+{
+ /* RISC-V does not support perf in guest mode. */
+ if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
+ pr_warn("RISC-V does not support perf in guest mode!");
+ return;
+ }
+
+ walk_stackframe(NULL, regs, fill_callchain, entry);
+}
diff --git a/arch/riscv/kernel/perf_regs.c b/arch/riscv/kernel/perf_regs.c
new file mode 100644
index 000000000000..04a38fbeb9c7
--- /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);
+}
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 5a9834503a2f..3836760d7aaf 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -56,6 +56,7 @@ void riscv_cpuid_to_hartid_mask(const struct cpumask *in, struct cpumask *out)
{
int cpu;
+ cpumask_clear(out);
for_each_cpu(cpu, in)
cpumask_set_cpu(cpuid_to_hartid_map(cpu), out);
}
@@ -78,13 +79,42 @@ static void ipi_stop(void)
wait_for_interrupt();
}
+static void send_ipi_mask(const struct cpumask *mask, enum ipi_message_type op)
+{
+ struct cpumask hartid_mask;
+ int cpu;
+
+ smp_mb__before_atomic();
+ for_each_cpu(cpu, mask)
+ set_bit(op, &ipi_data[cpu].bits);
+ smp_mb__after_atomic();
+
+ riscv_cpuid_to_hartid_mask(mask, &hartid_mask);
+ sbi_send_ipi(cpumask_bits(&hartid_mask));
+}
+
+static void send_ipi_single(int cpu, enum ipi_message_type op)
+{
+ int hartid = cpuid_to_hartid_map(cpu);
+
+ smp_mb__before_atomic();
+ set_bit(op, &ipi_data[cpu].bits);
+ smp_mb__after_atomic();
+
+ sbi_send_ipi(cpumask_bits(cpumask_of(hartid)));
+}
+
+static inline void clear_ipi(void)
+{
+ csr_clear(CSR_SIP, SIE_SSIE);
+}
+
void riscv_software_interrupt(void)
{
unsigned long *pending_ipis = &ipi_data[smp_processor_id()].bits;
unsigned long *stats = ipi_data[smp_processor_id()].stats;
- /* Clear pending IPI */
- csr_clear(CSR_SIP, SIE_SSIE);
+ clear_ipi();
while (true) {
unsigned long ops;
@@ -118,23 +148,6 @@ void riscv_software_interrupt(void)
}
}
-static void
-send_ipi_message(const struct cpumask *to_whom, enum ipi_message_type operation)
-{
- int cpuid, hartid;
- struct cpumask hartid_mask;
-
- cpumask_clear(&hartid_mask);
- mb();
- for_each_cpu(cpuid, to_whom) {
- set_bit(operation, &ipi_data[cpuid].bits);
- hartid = cpuid_to_hartid_map(cpuid);
- cpumask_set_cpu(hartid, &hartid_mask);
- }
- mb();
- sbi_send_ipi(cpumask_bits(&hartid_mask));
-}
-
static const char * const ipi_names[] = {
[IPI_RESCHEDULE] = "Rescheduling interrupts",
[IPI_CALL_FUNC] = "Function call interrupts",
@@ -156,12 +169,12 @@ void show_ipi_stats(struct seq_file *p, int prec)
void arch_send_call_function_ipi_mask(struct cpumask *mask)
{
- send_ipi_message(mask, IPI_CALL_FUNC);
+ send_ipi_mask(mask, IPI_CALL_FUNC);
}
void arch_send_call_function_single_ipi(int cpu)
{
- send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC);
+ send_ipi_single(cpu, IPI_CALL_FUNC);
}
void smp_send_stop(void)
@@ -176,7 +189,7 @@ void smp_send_stop(void)
if (system_state <= SYSTEM_RUNNING)
pr_crit("SMP: stopping secondary CPUs\n");
- send_ipi_message(&mask, IPI_CPU_STOP);
+ send_ipi_mask(&mask, IPI_CPU_STOP);
}
/* Wait up to one second for other CPUs to stop */
@@ -191,6 +204,5 @@ void smp_send_stop(void)
void smp_send_reschedule(int cpu)
{
- send_ipi_message(cpumask_of(cpu), IPI_RESCHEDULE);
+ send_ipi_single(cpu, IPI_RESCHEDULE);
}
-
diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c
index f15642715d1a..0940681d2f68 100644
--- a/arch/riscv/kernel/stacktrace.c
+++ b/arch/riscv/kernel/stacktrace.c
@@ -19,8 +19,8 @@ struct stackframe {
unsigned long ra;
};
-static void notrace walk_stackframe(struct task_struct *task,
- struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg)
+void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs,
+ bool (*fn)(unsigned long, void *), void *arg)
{
unsigned long fp, sp, pc;