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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /tools/perf/util/smt.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/perf/util/smt.c')
-rw-r--r--tools/perf/util/smt.c36
1 files changed, 36 insertions, 0 deletions
diff --git a/tools/perf/util/smt.c b/tools/perf/util/smt.c
new file mode 100644
index 0000000000..650e804d0a
--- /dev/null
+++ b/tools/perf/util/smt.c
@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <string.h>
+#include "api/fs/fs.h"
+#include "cputopo.h"
+#include "smt.h"
+
+bool smt_on(void)
+{
+ static bool cached;
+ static bool cached_result;
+ int fs_value;
+
+ if (cached)
+ return cached_result;
+
+ if (sysfs__read_int("devices/system/cpu/smt/active", &fs_value) >= 0)
+ cached_result = (fs_value == 1);
+ else
+ cached_result = cpu_topology__smt_on(online_topology());
+
+ cached = true;
+ return cached_result;
+}
+
+bool core_wide(bool system_wide, const char *user_requested_cpu_list)
+{
+ /* If not everything running on a core is being recorded then we can't use core_wide. */
+ if (!system_wide)
+ return false;
+
+ /* Cheap case that SMT is disabled and therefore we're inherently core_wide. */
+ if (!smt_on())
+ return true;
+
+ return cpu_topology__core_wide(online_topology(), user_requested_cpu_list);
+}