Commit 236dd583 authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo
Browse files

perf augmented_raw_syscalls: Add handler for "openat" 

I.e. for a syscall that has its second argument being a string, its
difficult these days to find 'open' being used in the wild :-)

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-yf3kbzirqrukd3fb2sp5qx4p@git.kernel.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent b119970a

tools/perf/builtin-trace.c

+1 −0
Original line number Diff line number Diff line
@@ -836,6 +836,7 @@ static struct syscall_fmt { 
	  .arg = { [0] = { .scnprintf = SCA_FDAT,	/* dfd */ },

		   [2] = { .scnprintf = SCA_OPEN_FLAGS, /* flags */ }, }, },

	{ .name	    = "openat",

	  .bpf_prog_name = { .sys_enter = "!syscalls:sys_enter_openat", },

	  .arg = { [0] = { .scnprintf = SCA_FDAT,	/* dfd */ },

		   [2] = { .scnprintf = SCA_OPEN_FLAGS, /* flags */ }, }, },

	{ .name	    = "perf_event_open",

tools/perf/examples/bpf/augmented_raw_syscalls.c

+17 −0
Original line number Diff line number Diff line
@@ -131,6 +131,23 @@ int sys_enter_open(struct syscall_enter_args *args) 
	return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, augmented_args, len);

}



SEC("!syscalls:sys_enter_openat")

int sys_enter_openat(struct syscall_enter_args *args)

{

	int key = 0;

	struct augmented_args_filename *augmented_args = bpf_map_lookup_elem(&augmented_filename_map, &key);

	const void *filename_arg = (const void *)args->args[1];

	unsigned int len = sizeof(augmented_args->args);



        if (augmented_args == NULL)

                return 1; /* Failure: don't filter */



	len += augmented_filename__read(&augmented_args->filename, filename_arg, sizeof(augmented_args->filename.value));



	/* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */

	return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, augmented_args, len);

}



SEC("raw_syscalls:sys_enter")

int sys_enter(struct syscall_enter_args *args)

{

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