perf tools: Do hugetlb handling in more systems

The csets:

0ac3348e5024 ("perf tools: Recognize hugetlb mapping as anon mapping")
d7e404af115b ("perf record: Mark MAP_HUGETLB when synthesizing mmap events")

Added code conditional on MAP_HUGETLB, to make it build in older systems
where that define wasn't available. Now that we grabbed copies of
uapi/linux/mmap.h to have all those definitions in tools/, use it so
that we can support building the tools for older systems (without the
MAP_HUGETLB define in its libc headers) using new kernels that support
such maps.

Cc: Adrian Hunter <[e-mail]>
Cc: David Ahern <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Wang Nan <[e-mail]>
Cc: Zefan Li <[e-mail]>
Link: http://lkml.kernel.org/n/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/event.c

···
 #include <linux/types.h>
-#include <sys/mman.h>
+#include <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */
 #include <api/fs/fs.h>
 #include "event.h"
 #include "debug.h"
···
 	bool truncation = false;
 	unsigned long long timeout = proc_map_timeout * 1000000ULL;
 	int rc = 0;
-#ifdef MAP_HUGETLB
 	const char *hugetlbfs_mnt = hugetlbfs__mountpoint();
 	int hugetlbfs_mnt_len = hugetlbfs_mnt ? strlen(hugetlbfs_mnt) : 0;
-#endif
 
 	if (machine__is_default_guest(machine))
 		return 0;
···
 
 		if (!strcmp(execname, ""))
 			strcpy(execname, anonstr);
-#ifdef MAP_HUGETLB
+
 		if (!strncmp(execname, hugetlbfs_mnt, hugetlbfs_mnt_len)) {
 			strcpy(execname, anonstr);
 			event->mmap2.flags |= MAP_HUGETLB;
 		}
-#endif
 
 		size = strlen(execname) + 1;
 		memcpy(event->mmap2.filename, execname, size);

tools/perf/util/map.c

···
 #include <string.h>
 #include <stdio.h>
 #include <unistd.h>
-#include <sys/mman.h>
+#include <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */
 #include "map.h"
 #include "thread.h"
 #include "strlist.h"
···
 
 static inline int is_anon_memory(const char *filename, u32 flags)
 {
-	u32 anon_flags = 0;
-
-#ifdef MAP_HUGETLB
-	anon_flags |= MAP_HUGETLB;
-#endif
-	return flags & anon_flags ||
+	return flags & MAP_HUGETLB ||
 	       !strcmp(filename, "//anon") ||
 	       !strncmp(filename, "/dev/zero", sizeof("/dev/zero") - 1) ||
 	       !strncmp(filename, "/anon_hugepage", sizeof("/anon_hugepage") - 1);