linux/tools/perf/trace/beauty/pkey_alloc.c
Arnaldo Carvalho de Melo 83bc9c371e perf trace beauty: Beautify pkey_{alloc,free,mprotect} arguments
Reuse 'mprotect' beautifiers for 'pkey_mprotect'.

System wide tracing pkey_alloc, pkey_free and pkey_mprotect calls, with
backtraces:

  # perf trace -e pkey_alloc,pkey_mprotect,pkey_free --max-stack=5
     0.000 ( 0.011 ms): pkey/7818 pkey_alloc(init_val: DISABLE_ACCESS|DISABLE_WRITE) = -1 EINVAL Invalid argument
                                       syscall (/usr/lib64/libc-2.25.so)
                                       pkey_alloc (/home/acme/c/pkey)
     0.022 ( 0.003 ms): pkey/7818 pkey_mprotect(start: 0x7f28c3890000, len: 4096, prot: READ|WRITE, pkey: -1) = 0
                                       syscall (/usr/lib64/libc-2.25.so)
                                       pkey_mprotect (/home/acme/c/pkey)
     0.030 ( 0.002 ms): pkey/7818 pkey_free(pkey: -1                               ) = -1 EINVAL Invalid argument
                                       syscall (/usr/lib64/libc-2.25.so)
                                       pkey_free (/home/acme/c/pkey)

The tools/include/uapi/asm-generic/mman-common.h file is used to find
the access rights defines for the pkey_alloc syscall second argument.

Since we have the detector of changes for the tools/include header files
versus its kernel origin (include/uapi/asm-generic/mman-common.h), we'll
get whatever new flag appears for that argument automatically.

This method should be used in other cases where it is easy to generate
those flags tables because the header has properly namespaced defines
like PKEY_DISABLE_ACCESS and PKEY_DISABLE_WRITE.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-3xq5312qlks7wtfzv2sk3nct@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-08-28 16:44:47 -03:00

51 lines
1.4 KiB
C

/*
* trace/beauty/pkey_alloc.c
*
* Copyright (C) 2017, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
*
* Released under the GPL v2. (and only v2, not any later version)
*/
#include "trace/beauty/beauty.h"
#include <linux/kernel.h>
#include <linux/log2.h>
static size_t pkey_alloc__scnprintf_access_rights(int access_rights, char *bf, size_t size)
{
int i, printed = 0;
#include "trace/beauty/generated/pkey_alloc_access_rights_array.c"
static DEFINE_STRARRAY(pkey_alloc_access_rights);
if (access_rights == 0) {
const char *s = strarray__pkey_alloc_access_rights.entries[0];
if (s)
return scnprintf(bf, size, "%s", s);
return scnprintf(bf, size, "%d", 0);
}
for (i = 1; i < strarray__pkey_alloc_access_rights.nr_entries; ++i) {
int bit = 1 << (i - 1);
if (!(access_rights & bit))
continue;
if (printed != 0)
printed += scnprintf(bf + printed, size - printed, "|");
if (strarray__pkey_alloc_access_rights.entries[i] != NULL)
printed += scnprintf(bf + printed, size - printed, "%s", strarray__pkey_alloc_access_rights.entries[i]);
else
printed += scnprintf(bf + printed, size - printed, "0x%#", bit);
}
return printed;
}
size_t syscall_arg__scnprintf_pkey_alloc_access_rights(char *bf, size_t size, struct syscall_arg *arg)
{
unsigned long cmd = arg->val;
return pkey_alloc__scnprintf_access_rights(cmd, bf, size);
}