From 2c81ca7fbaea06c2aed1aec66a88208d67e1e2de Mon Sep 17 00:00:00 2001 From: Nathan Lynch Date: Fri, 10 Feb 2023 12:41:58 -0600 Subject: [PATCH] powerpc/tracing: tracepoints for RTAS entry and exit Add two sets of tracepoints to be used around RTAS entry: * rtas_input/rtas_output, which emit the function name, its inputs, the returned status, and any other outputs. These produce an API-level record of OS<->RTAS activity. * rtas_ll_entry/rtas_ll_exit, which are lower-level and emit the entire contents of the parameter block (aka rtas_args) on entry and exit. Likely useful only for debugging. With uses of these tracepoints in do_enter_rtas() to be added in the following patch, examples of get-time-of-day and event-scan functions as rendered by trace-cmd (with some multi-line formatting manually imposed on the rtas_ll_* entries to avoid extremely long lines in the commit message): cat-36800 [059] 4978.518303: rtas_input: get-time-of-day arguments: cat-36800 [059] 4978.518306: rtas_ll_entry: token=3 nargs=0 nret=8 params: [0]=0x00000000 [1]=0x00000000 [2]=0x00000000 [3]=0x00000000 [4]=0x00000000 [5]=0x00000000 [6]=0x00000000 [7]=0x00000000 [8]=0x00000000 [9]=0x00000000 [10]=0x00000000 [11]=0x00000000 [12]=0x00000000 [13]=0x00000000 [14]=0x00000000 [15]=0x00000000 cat-36800 [059] 4978.518366: rtas_ll_exit: token=3 nargs=0 nret=8 params: [0]=0x00000000 [1]=0x000007e6 [2]=0x0000000b [3]=0x00000001 [4]=0x00000000 [5]=0x0000000e [6]=0x00000008 [7]=0x2e0dac40 [8]=0x00000000 [9]=0x00000000 [10]=0x00000000 [11]=0x00000000 [12]=0x00000000 [13]=0x00000000 [14]=0x00000000 [15]=0x00000000 cat-36800 [059] 4978.518366: rtas_output: get-time-of-day status: 0, other outputs: 2022 11 1 0 14 8 772648000 kworker/39:1-336 [039] 4982.731623: rtas_input: event-scan arguments: 4294967295 0 80484920 2048 kworker/39:1-336 [039] 4982.731626: rtas_ll_entry: token=6 nargs=4 nret=1 params: [0]=0xffffffff [1]=0x00000000 [2]=0x04cc1a38 [3]=0x00000800 [4]=0x00000000 [5]=0x0000000e [6]=0x00000008 [7]=0x2e0dac40 [8]=0x00000000 [9]=0x00000000 [10]=0x00000000 [11]=0x00000000 [12]=0x00000000 [13]=0x00000000 [14]=0x00000000 [15]=0x00000000 kworker/39:1-336 [039] 4982.731676: rtas_ll_exit: token=6 nargs=4 nret=1 params: [0]=0xffffffff [1]=0x00000000 [2]=0x04cc1a38 [3]=0x00000800 [4]=0x00000001 [5]=0x0000000e [6]=0x00000008 [7]=0x2e0dac40 [8]=0x00000000 [9]=0x00000000 [10]=0x00000000 [11]=0x00000000 [12]=0x00000000 [13]=0x00000000 [14]=0x00000000 [15]=0x00000000 kworker/39:1-336 [039] 4982.731677: rtas_output: event-scan status: 1, other outputs: Signed-off-by: Nathan Lynch Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230125-b4-powerpc-rtas-queue-v3-10-26929c8cce78@linux.ibm.com --- arch/powerpc/include/asm/trace.h | 103 +++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) diff --git a/arch/powerpc/include/asm/trace.h b/arch/powerpc/include/asm/trace.h index 08cd60cd70b7..82cc2c6704e6 100644 --- a/arch/powerpc/include/asm/trace.h +++ b/arch/powerpc/include/asm/trace.h @@ -119,6 +119,109 @@ TRACE_EVENT_FN_COND(hcall_exit, ); #endif +#ifdef CONFIG_PPC_RTAS + +#include + +TRACE_EVENT(rtas_input, + + TP_PROTO(struct rtas_args *rtas_args, const char *name), + + TP_ARGS(rtas_args, name), + + TP_STRUCT__entry( + __field(__u32, nargs) + __string(name, name) + __dynamic_array(__u32, inputs, be32_to_cpu(rtas_args->nargs)) + ), + + TP_fast_assign( + __entry->nargs = be32_to_cpu(rtas_args->nargs); + __assign_str(name, name); + be32_to_cpu_array(__get_dynamic_array(inputs), rtas_args->args, __entry->nargs); + ), + + TP_printk("%s arguments: %s", __get_str(name), + __print_array(__get_dynamic_array(inputs), __entry->nargs, 4) + ) +); + +TRACE_EVENT(rtas_output, + + TP_PROTO(struct rtas_args *rtas_args, const char *name), + + TP_ARGS(rtas_args, name), + + TP_STRUCT__entry( + __field(__u32, nr_other) + __field(__s32, status) + __string(name, name) + __dynamic_array(__u32, other_outputs, be32_to_cpu(rtas_args->nret) - 1) + ), + + TP_fast_assign( + __entry->nr_other = be32_to_cpu(rtas_args->nret) - 1; + __entry->status = be32_to_cpu(rtas_args->rets[0]); + __assign_str(name, name); + be32_to_cpu_array(__get_dynamic_array(other_outputs), + &rtas_args->rets[1], __entry->nr_other); + ), + + TP_printk("%s status: %d, other outputs: %s", __get_str(name), __entry->status, + __print_array(__get_dynamic_array(other_outputs), + __entry->nr_other, 4) + ) +); + +DECLARE_EVENT_CLASS(rtas_parameter_block, + + TP_PROTO(struct rtas_args *rtas_args), + + TP_ARGS(rtas_args), + + TP_STRUCT__entry( + __field(u32, token) + __field(u32, nargs) + __field(u32, nret) + __array(__u32, params, 16) + ), + + TP_fast_assign( + __entry->token = be32_to_cpu(rtas_args->token); + __entry->nargs = be32_to_cpu(rtas_args->nargs); + __entry->nret = be32_to_cpu(rtas_args->nret); + be32_to_cpu_array(__entry->params, rtas_args->args, ARRAY_SIZE(rtas_args->args)); + ), + + TP_printk("token=%u nargs=%u nret=%u params:" + " [0]=0x%08x [1]=0x%08x [2]=0x%08x [3]=0x%08x" + " [4]=0x%08x [5]=0x%08x [6]=0x%08x [7]=0x%08x" + " [8]=0x%08x [9]=0x%08x [10]=0x%08x [11]=0x%08x" + " [12]=0x%08x [13]=0x%08x [14]=0x%08x [15]=0x%08x", + __entry->token, __entry->nargs, __entry->nret, + __entry->params[0], __entry->params[1], __entry->params[2], __entry->params[3], + __entry->params[4], __entry->params[5], __entry->params[6], __entry->params[7], + __entry->params[8], __entry->params[9], __entry->params[10], __entry->params[11], + __entry->params[12], __entry->params[13], __entry->params[14], __entry->params[15] + ) +); + +DEFINE_EVENT(rtas_parameter_block, rtas_ll_entry, + + TP_PROTO(struct rtas_args *rtas_args), + + TP_ARGS(rtas_args) +); + +DEFINE_EVENT(rtas_parameter_block, rtas_ll_exit, + + TP_PROTO(struct rtas_args *rtas_args), + + TP_ARGS(rtas_args) +); + +#endif /* CONFIG_PPC_RTAS */ + #ifdef CONFIG_PPC_POWERNV extern int opal_tracepoint_regfunc(void); extern void opal_tracepoint_unregfunc(void); -- 2.25.1