The default breakpoint length is "sizeof(long)" however this is
incorrect on platforms like Aarch64 where sizeof(long) is 8 but the
breakpoint length is 4. Add a helper function that can be used to
determine the correct breakpoint length, in this change it just
returns the existing default sizeof(long) value.

Use the helper in the bp_account test so that, when modifying the
event from a watchpoint to a breakpoint, the breakpoint length is
appropriate for the architecture and not just sizeof(long).

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/tests/bp_account.c         | 4 +++-
 tools/perf/tests/bp_signal.c          | 3 ++-
 tools/perf/tests/bp_signal_overflow.c | 3 ++-
 tools/perf/tests/parse-events.c       | 3 ++-
 tools/perf/util/parse-events.c        | 7 ++++++-
 tools/perf/util/parse-events.h        | 2 ++
 6 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/tools/perf/tests/bp_account.c b/tools/perf/tests/bp_account.c
index 6f921db33cf9..4cb7d486b5c1 100644
--- a/tools/perf/tests/bp_account.c
+++ b/tools/perf/tests/bp_account.c
@@ -16,6 +16,7 @@
 #include "tests.h"
 #include "debug.h"
 #include "event.h"
+#include "parse-events.h"
 #include "../perf-sys.h"
 #include "cloexec.h"
 
@@ -50,7 +51,7 @@ static int __event(bool is_x, void *addr, struct perf_event_attr *attr)
 	attr->config = 0;
 	attr->bp_type = is_x ? HW_BREAKPOINT_X : HW_BREAKPOINT_W;
 	attr->bp_addr = (unsigned long) addr;
-	attr->bp_len = sizeof(long);
+	attr->bp_len = is_x ? default_breakpoint_len() : sizeof(long);
 
 	attr->sample_period = 1;
 	attr->sample_type = PERF_SAMPLE_IP;
@@ -92,6 +93,7 @@ static int bp_accounting(int wp_cnt, int share)
 	attr_mod = attr;
 	attr_mod.bp_type = HW_BREAKPOINT_X;
 	attr_mod.bp_addr = (unsigned long) test_function;
+	attr_mod.bp_len = default_breakpoint_len();
 
 	ret = ioctl(fd[0], PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr_mod);
 	TEST_ASSERT_VAL("failed to modify wp\n", ret == 0);
diff --git a/tools/perf/tests/bp_signal.c b/tools/perf/tests/bp_signal.c
index 1f2908f02389..3faeb5b6fe0b 100644
--- a/tools/perf/tests/bp_signal.c
+++ b/tools/perf/tests/bp_signal.c
@@ -26,6 +26,7 @@
 #include "tests.h"
 #include "debug.h"
 #include "event.h"
+#include "parse-events.h"
 #include "perf-sys.h"
 #include "cloexec.h"
 
@@ -111,7 +112,7 @@ static int __event(bool is_x, void *addr, int sig)
 	pe.config = 0;
 	pe.bp_type = is_x ? HW_BREAKPOINT_X : HW_BREAKPOINT_W;
 	pe.bp_addr = (unsigned long) addr;
-	pe.bp_len = sizeof(long);
+	pe.bp_len = is_x ? default_breakpoint_len() : sizeof(long);
 
 	pe.sample_period = 1;
 	pe.sample_type = PERF_SAMPLE_IP;
diff --git a/tools/perf/tests/bp_signal_overflow.c b/tools/perf/tests/bp_signal_overflow.c
index 4e897c2cf26b..ee560e156be6 100644
--- a/tools/perf/tests/bp_signal_overflow.c
+++ b/tools/perf/tests/bp_signal_overflow.c
@@ -25,6 +25,7 @@
 #include "tests.h"
 #include "debug.h"
 #include "event.h"
+#include "parse-events.h"
 #include "../perf-sys.h"
 #include "cloexec.h"
 
@@ -88,7 +89,7 @@ static int test__bp_signal_overflow(struct test_suite *test __maybe_unused, int
 	pe.config = 0;
 	pe.bp_type = HW_BREAKPOINT_X;
 	pe.bp_addr = (unsigned long) test_function;
-	pe.bp_len = sizeof(long);
+	pe.bp_len = default_breakpoint_len();
 
 	pe.sample_period = THRESHOLD;
 	pe.sample_type = PERF_SAMPLE_IP;
diff --git a/tools/perf/tests/parse-events.c b/tools/perf/tests/parse-events.c
index edc2adcf1bae..0681653b12d2 100644
--- a/tools/perf/tests/parse-events.c
+++ b/tools/perf/tests/parse-events.c
@@ -5,6 +5,7 @@
 #include <api/fs/fs.h>
 #include "tests.h"
 #include "debug.h"
+#include "parse-events.h"
 #include "pmu.h"
 #include "pmus.h"
 #include <dirent.h>
@@ -262,7 +263,7 @@ static int test__checkevent_breakpoint_x(struct evlist *evlist)
 	TEST_ASSERT_VAL("wrong config", test_config(evsel, 0));
 	TEST_ASSERT_VAL("wrong bp_type",
 			HW_BREAKPOINT_X == evsel->core.attr.bp_type);
-	TEST_ASSERT_VAL("wrong bp_len", sizeof(long) == evsel->core.attr.bp_len);
+	TEST_ASSERT_VAL("wrong bp_len", default_breakpoint_len() == (int)evsel->core.attr.bp_len);
 	return TEST_OK;
 }
 
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index fab01ba54e34..dfb951bb184b 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -670,6 +670,11 @@ static int add_tracepoint_multi_sys(struct parse_events_state *parse_state,
 }
 #endif /* HAVE_LIBTRACEEVENT */
 
+int default_breakpoint_len(void)
+{
+	return sizeof(long);
+}
+
 static int
 parse_breakpoint_type(const char *type, struct perf_event_attr *attr)
 {
@@ -728,7 +733,7 @@ int parse_events_add_breakpoint(struct parse_events_state *parse_state,
 	/* Provide some defaults if len is not specified */
 	if (!len) {
 		if (attr.bp_type == HW_BREAKPOINT_X)
-			len = sizeof(long);
+			len = default_breakpoint_len();
 		else
 			len = HW_BREAKPOINT_LEN_4;
 	}
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index b735cd9e0acf..f79d076cd1bd 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -286,4 +286,6 @@ static inline bool is_sdt_event(char *str __maybe_unused)
 }
 #endif /* HAVE_LIBELF_SUPPORT */
 
+int default_breakpoint_len(void);
+
 #endif /* __PERF_PARSE_EVENTS_H */
-- 
2.46.0.469.g59c65b2a67-goog

Hi Ian,

kernel test robot noticed the following build warnings:

[auto build test WARNING on perf-tools-next/perf-tools-next]
[also build test WARNING on tip/perf/core perf-tools/perf-tools linus/master v6.11-rc5 next-20240830]
[cannot apply to acme/perf/core]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Ian-Rogers/perf-pmus-Fix-name-comparisons-on-32-bit-systems/20240831-150738
base:   https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git perf-tools-next
patch link:    https://lore.kernel.org/r/20240831070415.506194-5-irogers%40google.com
patch subject: [PATCH v1 4/6] perf parse-events: Add default_breakpoint_len helper
:::::: branch date: 26 hours ago
:::::: commit date: 26 hours ago
compiler: clang version 18.1.5 (https://github.com/llvm/llvm-project 617a15a9eac96088ae5e9134248d8236e34b91b1)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/r/202409011605.G583kE4G-lkp@intel.com/

includecheck warnings: (new ones prefixed by >>)
>> tools/perf/tests/parse-events.c: parse-events.h is included more than once.

vim +2 tools/perf/tests/parse-events.c

   > 2	#include "parse-events.h"
     3	#include "evsel.h"
     4	#include "evlist.h"
     5	#include <api/fs/fs.h>
     6	#include "tests.h"
     7	#include "debug.h"
   > 8	#include "parse-events.h"
     9	#include "pmu.h"
    10	#include "pmus.h"
    11	#include <dirent.h>
    12	#include <errno.h>
    13	#include "fncache.h"
    14	#include <sys/types.h>
    15	#include <sys/stat.h>
    16	#include <unistd.h>
    17	#include <linux/kernel.h>
    18	#include <linux/hw_breakpoint.h>
    19	#include <api/fs/tracing_path.h>
    20	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki