[libvirt] [PATCH v2 2/7] process: Add virProcessGetMaxMemLock()
This function can be used to retrieve the current locked memory
limit for a process, so that the setting can be later restored.
Add a configure check for getrlimit(), which we now use.
---
configure.ac | 2 +-
src/libvirt_private.syms | 1 +
src/util/virprocess.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
src/util/virprocess.h | 2 ++
4 files changed, 49 insertions(+), 1 deletion(-)
diff --git a/configure.ac b/configure.ac
index 98cf210..25fdfe2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -279,7 +279,7 @@ AC_CHECK_SIZEOF([long])
dnl Availability of various common functions (non-fatal if missing),
dnl and various less common threadsafe functions
AC_CHECK_FUNCS_ONCE([cfmakeraw fallocate geteuid getgid getgrnam_r \
- getmntent_r getpwuid_r getuid kill mmap newlocale posix_fallocate \
+ getmntent_r getpwuid_r getrlimit getuid kill mmap newlocale posix_fallocate \
posix_memalign prlimit regexec sched_getaffinity setgroups setns \
setrlimit symlink sysctlbyname getifaddrs sched_setscheduler])
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 55822ae..0b5ddc1 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -2040,6 +2040,7 @@ virPortAllocatorSetUsed;
virProcessAbort;
virProcessExitWithStatus;
virProcessGetAffinity;
+virProcessGetMaxMemLock;
virProcessGetNamespaces;
virProcessGetPids;
virProcessGetStartTime;
diff --git a/src/util/virprocess.c b/src/util/virprocess.c
index 9b38834..277b3bc 100644
--- a/src/util/virprocess.c
+++ b/src/util/virprocess.c
@@ -788,6 +788,51 @@ virProcessSetMaxMemLock(pid_t pid ATTRIBUTE_UNUSED, unsigned long
long bytes)
}
#endif /* ! (HAVE_SETRLIMIT && defined(RLIMIT_MEMLOCK)) */
+#if HAVE_GETRLIMIT && defined(RLIMIT_MEMLOCK)
+int
+virProcessGetMaxMemLock(pid_t pid,
+ unsigned long long *bytes)
+{
+ struct rlimit rlim;
+
+ if (!bytes)
+ return 0;
+
+ if (pid == 0) {
+ if (getrlimit(RLIMIT_MEMLOCK, &rlim) < 0) {
+ virReportSystemError(errno,
+ "%s",
+ _("cannot get locked memory limit"));
+ return -1;
+ }
+ } else {
+ if (virProcessPrLimit(pid, RLIMIT_MEMLOCK, NULL, &rlim) < 0) {
+ virReportSystemError(errno,
+ _("cannot get locked memory limit "
+ "of process %lld"),
+ (long long int) pid);
+ return -1;
+ }
+ }
+
+ /* virProcessSetMaxMemLock() sets both rlim_cur and rlim_max to the
+ * same value, so we can retrieve just rlim_max here */
+ *bytes = rlim.rlim_max;
+
+ return 0;
+}
+#else /* ! (HAVE_GETRLIMIT && defined(RLIMIT_MEMLOCK)) */
+int
+virProcessGetMaxMemLock(pid_t pid ATTRIBUTE_UNUSED,
+ unsigned long long *bytes)
+{
+ if (!bytes)
+ return 0;
+
+ virReportSystemError(ENOSYS, "%s", _("Not supported on this
platform"));
+ return -1;
+}
+#endif /* ! (HAVE_GETRLIMIT && defined(RLIMIT_MEMLOCK)) */
#if HAVE_SETRLIMIT && defined(RLIMIT_NPROC)
int
diff --git a/src/util/virprocess.h b/src/util/virprocess.h
index 1768009..a7a1fe9 100644
--- a/src/util/virprocess.h
+++ b/src/util/virprocess.h
@@ -76,6 +76,8 @@ int virProcessSetMaxMemLock(pid_t pid, unsigned long long bytes);
int virProcessSetMaxProcesses(pid_t pid, unsigned int procs);
int virProcessSetMaxFiles(pid_t pid, unsigned int files);
+int virProcessGetMaxMemLock(pid_t pid, unsigned long long *bytes);
+
/* Callback to run code within the mount namespace tied to the given
* pid. This function must use only async-signal-safe functions, as
* it gets run after a fork of a multi-threaded process. The return
--
2.5.0