diff --git a/tools/testing/selftests/mm/vm_util.c
b/tools/testing/selftests/mm/vm_util.c
index 1357e2d6a7b6..115422e9eb68 100644
--- a/tools/testing/selftests/mm/vm_util.c
+++ b/tools/testing/selftests/mm/vm_util.c
@@ -486,3 +486,74 @@ int close_procmap(struct procmap_fd *procmap)
{
return close(procmap->fd);
}
+
I think we should just let all these functions open/close the fds. So
there will not be a need to pass in the fds.
+int ksm_use_zero_pages(int ksm_use_zero_pages_fd)
+{
+ return write(ksm_use_zero_pages_fd, "1", 1);
+}
+
+int ksm_start_and_merge(int ksm_fd)
+{
+ return write(ksm_fd, "1", 1);
> +}> +
+int ksm_stop_and_unmerge(int ksm_fd)
+{
+ return write(ksm_fd, "2", 1);
+}
Can we make all these functions return "0" on success? This, way, the
"write" will be an internal implementation detail.
E.g.,
int ksm_stop_and_unmerge(void)
{
int ksm_fd = ...
ssize_t ret;
...
ret = write(ksm_fd, "2", 1);
close(ksm_fd);
return ret == 1 ? 0 : ret;
}
+
+long ksm_get_full_scans(int ksm_full_scans_fd)
+{
+ char buf[10];
+ ssize_t ret;
+
+ ret = pread(ksm_full_scans_fd, buf, sizeof(buf) - 1, 0);
+ if (ret <= 0)
+ return -errno;
+ buf[ret] = 0;
+
+ return strtol(buf, NULL, 10);
+}
+
+long ksm_get_self_merging_pages(int proc_self_ksm_merging_pages_fd)
+{
+ char buf[10];
+ ssize_t ret;
+
+ if (proc_self_ksm_merging_pages_fd < 0)
+ return proc_self_ksm_merging_pages_fd;
+
+ ret = pread(proc_self_ksm_merging_pages_fd, buf, sizeof(buf) - 1, 0);
+ if (ret <= 0)
+ return -errno;
+ buf[ret] = 0;
+
+ return strtol(buf, NULL, 10);
+}
+
+long ksm_get_self_zero_pages(int proc_self_ksm_stat_fd)
+{
+ char buf[200];
+ char *substr_ksm_zero;
+ size_t value_pos;
+ ssize_t read_size;
+ unsigned long my_ksm_zero_pages;
+
+ if (!proc_self_ksm_stat_fd)
+ return 0;
+
+ read_size = pread(proc_self_ksm_stat_fd, buf, sizeof(buf) - 1, 0);
+ if (read_size < 0)
+ return -errno;
+
+ buf[read_size] = 0;
+
+ substr_ksm_zero = strstr(buf, "ksm_zero_pages");
+ if (!substr_ksm_zero)
+ return 0;
+
+ value_pos = strcspn(substr_ksm_zero, "0123456789");
+ my_ksm_zero_pages = strtol(substr_ksm_zero + value_pos, NULL, 10);
+
+ return my_ksm_zero_pages;
+}
diff --git a/tools/testing/selftests/mm/vm_util.h
b/tools/testing/selftests/mm/vm_util.h
index 9211ba640d9c..99c1b1aa1813 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -95,6 +95,13 @@ static inline int open_self_procmap(struct procmap_fd
*procmap_out)
return open_procmap(pid, procmap_out);
}
+int ksm_use_zero_pages(int ksm_use_zero_pages_fd);
+int ksm_start_and_merge(int ksm_fd);
+int ksm_stop_and_unmerge(int ksm_fd);
+long ksm_get_full_scans(int ksm_full_scans_fd);
+long ksm_get_self_merging_pages(int proc_self_ksm_merging_pages_fd);
+long ksm_get_self_zero_pages(int proc_self_ksm_stat_fd);
With the fd parameters removed, that interface will look quite neat I think.
--
Cheers,
David / dhildenb
