[LTP] [PATCH ltp] Add 4 more cases for Intel PT.

[Cyril Hrubis]

Hi!
> +/* 10/2018 Add full trace check test case */
> +/* 2/2019  Add snapshot/disable branch/user/kernel trace */

We keep the history in git, please do not add comments like these.

>  #include <sched.h>
>  #include <stdlib.h>
>  #include <stdio.h>
> @@ -40,22 +42,36 @@ int fde = -1;
>  //map head and size
>  uint64_t **bufm;
>  long buhsz;
> -
> -static uint64_t **create_map(int fde, long bufsize)
> +char *str_mode;
> +char *str_exclude_info;
> +char *str_branch_flag;
> +int mode = 1;
> +int exclude_info = 3;
> +int branch_flag = 1;
> +
> +static uint64_t **create_map(int fde, long bufsize, int flag)
                                                           ^
							   Can we call
							   this rw_flag?

>  {
>  	uint64_t **buf_ev;
> +	int pro_flag;
>  	struct perf_event_mmap_page *pc;
>  
>  	buf_ev = SAFE_MALLOC(2*sizeof(uint64_t *));
>  	buf_ev[0] = NULL;
>  	buf_ev[1] = NULL;
> +	if (flag == 1) {
> +		tst_res(TINFO, "memory will be r/w!");
                                ^
				Can you be more specific here?

You map one of the buffers read only if the flag is not set but the
option is called full/snapshot trace, it does not explain the difference
much.

> +		pro_flag = PROT_READ | PROT_WRITE;
> +	} else {
> +		tst_res(TINFO, "memory will be r only!");
> +		pro_flag = PROT_READ;
> +	}
>  	buf_ev[0] = SAFE_MMAP(NULL, INTEL_PT_MEMSIZE, PROT_READ | PROT_WRITE,
>  							MAP_SHARED, fde, 0);
>  
>  	pc = (struct perf_event_mmap_page *)buf_ev[0];
>  	pc->aux_offset = INTEL_PT_MEMSIZE;
>  	pc->aux_size = bufsize;
> -	buf_ev[1] = SAFE_MMAP(NULL, bufsize, PROT_READ | PROT_WRITE,
> +	buf_ev[1] = SAFE_MMAP(NULL, bufsize, pro_flag,
>  					MAP_SHARED, fde, INTEL_PT_MEMSIZE);
>  	return buf_ev;
>  }
> @@ -89,7 +105,7 @@ static void del_map(uint64_t **buf_ev, long bufsize)
>  	free(buf_ev);
>  }
>  
> -static void intel_pt_full_trace_check(void)
> +static void intel_pt_trace_check(void)
>  {
>  	uint64_t aux_head = 0;
>  	struct perf_event_mmap_page *pmp;
> @@ -108,7 +124,19 @@ static void intel_pt_full_trace_check(void)
>  		return;
>  	}
>  
> -	tst_res(TPASS, "perf trace full mode is passed!");
> +	tst_res(TPASS, "perf trace test is passed!");
> +}
> +
> +static void parse_options(void)
> +{
> +	if (tst_parse_int(str_mode, &mode, 0, 1))
> +		tst_brk(TBROK, "Invalid mode '%s'", str_mode);
> +
> +	if (tst_parse_int(str_exclude_info, &exclude_info, 1, 2))
> +		tst_brk(TBROK, "Invalid exclude info '%s'", str_exclude_info);
> +
> +	if (tst_parse_int(str_branch_flag, &branch_flag, 0, 1))
> +		tst_brk(TBROK, "Invalid branch flag '%s'", str_branch_flag);
>  }
>  
>  static void setup(void)
> @@ -116,6 +144,9 @@ static void setup(void)
>  	struct perf_event_attr attr = {};
>  
>  	buhsz = 2 * PAGESIZE;
> +
> +	parse_options();
> +
>  	if (access(INTEL_PT_PATH, F_OK)) {
>  		tst_brk(TCONF,
>  			"Requires Intel Core 5th+ generation (Broadwell and newer)"
> @@ -130,9 +161,24 @@ static void setup(void)
>  	attr.config	= BIT(intel_pt_pmu_value(INTEL_PT_FORMAT_TSC)) |
>  				BIT(intel_pt_pmu_value(INTEL_PT_FORMAT_NRT));
>  	attr.size	= sizeof(struct perf_event_attr);
> -	attr.exclude_kernel		= 0;
> -	attr.exclude_user		= 0;
> -	attr.mmap			= 1;
> +	attr.mmap	= 1;

Removing whitespaces here is kind of useless change.

> +	if (branch_flag == 0) {
> +		tst_res(TINFO, "Intel PT will disable branch trace!");
                                                                  ^
				Why does all the messages include
				exclamation mark? These are just info
				messages anyways.

> +		attr.config |= 1;
> +	}
> +
> +	attr.exclude_kernel	= 0;
> +	attr.exclude_user	= 0;
> +
> +	if (exclude_info == 1) {
> +		tst_res(TINFO, "Intel PT will exclude user trace!");
> +		attr.exclude_user = 1;
> +	}
> +
> +	if (exclude_info == 2) {
> +		tst_res(TINFO, "Intel PT will exclude kernel trace!");
> +		attr.exclude_kernel = 1;
> +	}
>  
>  	/* only get trace for own pid */
>  	fde = tst_syscall(__NR_perf_event_open, &attr, 0, -1, -1, 0);
> @@ -142,7 +188,7 @@ static void setup(void)
>  		return;
>  	}
>  	bufm = NULL;
> -	bufm = create_map(fde, buhsz);
> +	bufm = create_map(fde, buhsz, mode);
>  
>  }
>  
> @@ -154,8 +200,17 @@ static void cleanup(void)
>  	del_map(bufm, buhsz);
>  }
>  
> +static struct tst_option options[] = {
> +	{"m:", &str_mode, "-m different mode, as full trace or snapshot trace"},

This parameter is binary switch so there is no point having it as a flag
with a value. We can just pass "m" instead of "m:" there then do if ()
on the string pointer passed here.

> +	{"e:", &str_exclude_info, "-e exclude info, 1->user, 2->kernel"},

It would be a bit more user-friendly if we passed strings "user" and
"kernel" insteead of 1 and 2 as the flag parameters.

> +	{"b:", &str_branch_flag, "-b if disable branch trace"},

Here as well.

> +	{NULL, NULL, NULL}
> +};
> +
> +
>  static struct tst_test test = {
> -	.test_all = intel_pt_full_trace_check,
> +	.test_all = intel_pt_trace_check,
> +	.options = options,
>  	.min_kver = "4.1",
>  	.setup = setup,
>  	.cleanup = cleanup,
> -- 
> 2.14.1
> 
> 
> -- 
> Mailing list info: https://lists.linux.it/listinfo/ltp

-- 
Cyril Hrubis
chrubis@suse.cz