[PATCH 5/7] powerpc/selftests/perf-hwbreak: Coalesce event creation code

From: Ravi Bangoria
Date: Thu Jul 23 2020 - 06:22:54 EST


perf-hwbreak selftest opens hw-breakpoint event at multiple places for
which it has same code repeated. Coalesce that code into a function.

Signed-off-by: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxx>
---
.../selftests/powerpc/ptrace/perf-hwbreak.c | 78 +++++++++----------
1 file changed, 38 insertions(+), 40 deletions(-)

diff --git a/tools/testing/selftests/powerpc/ptrace/perf-hwbreak.c b/tools/testing/selftests/powerpc/ptrace/perf-hwbreak.c
index c1f324afdbf3..bde475341c8a 100644
--- a/tools/testing/selftests/powerpc/ptrace/perf-hwbreak.c
+++ b/tools/testing/selftests/powerpc/ptrace/perf-hwbreak.c
@@ -34,28 +34,46 @@

#define DAWR_LENGTH_MAX ((0x3f + 1) * 8)

-static inline int sys_perf_event_open(struct perf_event_attr *attr, pid_t pid,
- int cpu, int group_fd,
- unsigned long flags)
+static void perf_event_attr_set(struct perf_event_attr *attr,
+ __u32 type, __u64 addr, __u64 len,
+ bool exclude_user)
{
- attr->size = sizeof(*attr);
- return syscall(__NR_perf_event_open, attr, pid, cpu, group_fd, flags);
+ memset(attr, 0, sizeof(struct perf_event_attr));
+ attr->type = PERF_TYPE_BREAKPOINT;
+ attr->size = sizeof(struct perf_event_attr);
+ attr->bp_type = type;
+ attr->bp_addr = addr;
+ attr->bp_len = len;
+ attr->exclude_kernel = 1;
+ attr->exclude_hv = 1;
+ attr->exclude_guest = 1;
+ attr->exclude_user = exclude_user;
+ attr->disabled = 1;
}

-static inline bool breakpoint_test(int len)
+static int
+perf_process_event_open_exclude_user(__u32 type, __u64 addr, __u64 len, bool exclude_user)
{
struct perf_event_attr attr;
+
+ perf_event_attr_set(&attr, type, addr, len, exclude_user);
+ return syscall(__NR_perf_event_open, &attr, getpid(), -1, -1, 0);
+}
+
+static int perf_process_event_open(__u32 type, __u64 addr, __u64 len)
+{
+ struct perf_event_attr attr;
+
+ perf_event_attr_set(&attr, type, addr, len, 0);
+ return syscall(__NR_perf_event_open, &attr, getpid(), -1, -1, 0);
+}
+
+static inline bool breakpoint_test(int len)
+{
int fd;

- /* setup counters */
- memset(&attr, 0, sizeof(attr));
- attr.disabled = 1;
- attr.type = PERF_TYPE_BREAKPOINT;
- attr.bp_type = HW_BREAKPOINT_R;
/* bp_addr can point anywhere but needs to be aligned */
- attr.bp_addr = (__u64)(&attr) & 0xfffffffffffff800;
- attr.bp_len = len;
- fd = sys_perf_event_open(&attr, 0, -1, -1, 0);
+ fd = perf_process_event_open(HW_BREAKPOINT_R, (__u64)(&fd) & 0xfffffffffffff800, len);
if (fd < 0)
return false;
close(fd);
@@ -75,7 +93,6 @@ static inline bool dawr_supported(void)
static int runtestsingle(int readwriteflag, int exclude_user, int arraytest)
{
int i,j;
- struct perf_event_attr attr;
size_t res;
unsigned long long breaks, needed;
int readint;
@@ -94,19 +111,11 @@ static int runtestsingle(int readwriteflag, int exclude_user, int arraytest)
if (arraytest)
ptr = &readintalign[0];

- /* setup counters */
- memset(&attr, 0, sizeof(attr));
- attr.disabled = 1;
- attr.type = PERF_TYPE_BREAKPOINT;
- attr.bp_type = readwriteflag;
- attr.bp_addr = (__u64)ptr;
- attr.bp_len = sizeof(int);
- if (arraytest)
- attr.bp_len = DAWR_LENGTH_MAX;
- attr.exclude_user = exclude_user;
- break_fd = sys_perf_event_open(&attr, 0, -1, -1, 0);
+ break_fd = perf_process_event_open_exclude_user(readwriteflag, (__u64)ptr,
+ arraytest ? DAWR_LENGTH_MAX : sizeof(int),
+ exclude_user);
if (break_fd < 0) {
- perror("sys_perf_event_open");
+ perror("perf_process_event_open_exclude_user");
exit(1);
}

@@ -153,7 +162,6 @@ static int runtest_dar_outside(void)
void *target;
volatile __u16 temp16;
volatile __u64 temp64;
- struct perf_event_attr attr;
int break_fd;
unsigned long long breaks;
int fail = 0;
@@ -165,21 +173,11 @@ static int runtest_dar_outside(void)
exit(EXIT_FAILURE);
}

- /* setup counters */
- memset(&attr, 0, sizeof(attr));
- attr.disabled = 1;
- attr.type = PERF_TYPE_BREAKPOINT;
- attr.exclude_kernel = 1;
- attr.exclude_hv = 1;
- attr.exclude_guest = 1;
- attr.bp_type = HW_BREAKPOINT_RW;
/* watch middle half of target array */
- attr.bp_addr = (__u64)(target + 2);
- attr.bp_len = 4;
- break_fd = sys_perf_event_open(&attr, 0, -1, -1, 0);
+ break_fd = perf_process_event_open(HW_BREAKPOINT_RW, (__u64)(target + 2), 4);
if (break_fd < 0) {
free(target);
- perror("sys_perf_event_open");
+ perror("perf_process_event_open");
exit(EXIT_FAILURE);
}

--
2.26.2