Add more unit tests for possible_cpus_array_len

[lttng-ust.git] / src / common / smp.h

diff --git a/src/common/smp.h b/src/common/smp.h
index f908b6c6ef39c5e9f8868ec15b19a78f80b54d83..0a8433f3dc08222e287e79cab4ed7ce7ec3eed2a 100644 (file)
--- a/src/common/smp.h
+++ b/src/common/smp.h
@@ -9,6 +9,18 @@
 
 #define LTTNG_UST_CPUMASK_SIZE 4096
 
+/*
+ * Get a CPU mask string from sysfs.
+ *
+ * buf: the buffer where the mask will be read.
+ * max_bytes: the maximum number of bytes to write in the buffer.
+ * path: file path to read the mask from.
+ *
+ * Returns the number of bytes read or -1 on error.
+ */
+int get_cpu_mask_from_sysfs(char *buf, size_t max_bytes, const char *path)
+       __attribute__((visibility("hidden")));
+
 /*
  * Get the CPU possible mask string from sysfs.
  *
@@ -20,6 +32,21 @@
 int get_possible_cpu_mask_from_sysfs(char *buf, size_t max_bytes)
        __attribute__((visibility("hidden")));
 
+/*
+ * Get the highest CPU id from sysfs.
+ *
+ * Iterate on all the folders in "/sys/devices/system/cpu" that start with
+ * "cpu" followed by an integer, keep the highest CPU id encountered during
+ * this iteration and add 1 to get a number of CPUs.
+ *
+ * Returns the highest CPU id, or -1 on error.
+ */
+int get_max_cpuid_from_sysfs(void)
+       __attribute__((visibility("hidden")));
+
+int _get_max_cpuid_from_sysfs(const char *path)
+       __attribute__((visibility("hidden")));
+
 /*
  * Get the number of possible CPUs in the system from either
  * sysconf(_SC_NPROCESSORS_CONF) or some other mechanism depending on the libc.