wireguard-linux/arch/csky/kernel/ftrace.c, branch jd/unified-crypt-queue

csky/ftrace: Fixup ftrace_modify_code deadlock without CPU_HAS_ICACHE_INS

2020-03-31T14:15:42Z

If ICACHE_INS is not supported, we use IPI to sync icache on each core. But ftrace_modify_code is called from stop_machine from default implementation of arch_ftrace_update_code and stop_machine callback is irq_disabled. When you call ipi with irq_disabled, a deadlock will happen. We couldn't use icache_flush with irq_disabled, but startup make_nop is specific case and it needn't ipi other cores. Signed-off-by: Guo Ren

csky: Implement ftrace with regs

2020-03-08T12:55:14Z

This patch implements FTRACE_WITH_REGS for csky, which allows a traced function's arguments (and some other registers) to be captured into a struct pt_regs, allowing these to be inspected and/or modified. Signed-off-by: Guo Ren

csky/ftrace: Add dynamic function tracer (include graph tracer)

2019-04-22T05:44:57Z

Support dynamic ftrace including dynamic graph tracer. Gcc-csky with -pg will produce call site in every function prologue and we can use these call site to hook trace function. gcc with -pg origin call site: push lr jbsr _mcount nop32 nop32 If the (callee - caller)'s offset is in range of bsr instruction, we'll modify code with: push lr bsr _mcount nop32 nop32 Else if the (callee - caller)'s offset is out of bsr instrunction, we'll modify code with: push lr movih r26, ... ori r26, ... jsr r26 (r26 is reserved for jsr link reg in csky abiv2 spec.) Signed-off-by: Guo Ren

csky: ftrace call graph supported.

2018-12-31T15:17:23Z

With csky-gcc -pg -mbacktrace, ftrace call graph supported. Signed-off-by: Guo Ren

csky: basic ftrace supported

2018-12-31T15:16:46Z

When gcc with -pg, it'll add _mcount stub in every function. We need implement the _mcount in kernel and ftrace depends on stackstrace. To do: call-graph, dynamic ftrace Signed-off-by: Guo Ren