Merge changes I627e47c6,Ic85892b4 into nyc-mr1-dev-plus-aosp
* changes:
Revert "Add boost to increase the load on newly-forked zygote processes."
Make sure Zygote is running at process priority 0 after VM has started.
diff --git a/core/jni/Android.mk b/core/jni/Android.mk
index 5fcde8b..70e9004 100644
--- a/core/jni/Android.mk
+++ b/core/jni/Android.mk
@@ -20,10 +20,6 @@
LOCAL_CFLAGS += -DENABLE_CPUSETS
endif
-ifneq ($(ENABLE_SCHED_BOOST),)
- LOCAL_CFLAGS += -DENABLE_SCHED_BOOST
-endif
-
LOCAL_CFLAGS += -DGL_GLEXT_PROTOTYPES -DEGL_EGLEXT_PROTOTYPES
LOCAL_CFLAGS += -DU_USING_ICU_NAMESPACE=0
diff --git a/core/jni/com_android_internal_os_Zygote.cpp b/core/jni/com_android_internal_os_Zygote.cpp
index 894e104..da059e3 100644
--- a/core/jni/com_android_internal_os_Zygote.cpp
+++ b/core/jni/com_android_internal_os_Zygote.cpp
@@ -37,6 +37,7 @@
#include <sys/prctl.h>
#include <sys/resource.h>
#include <sys/stat.h>
+#include <sys/time.h>
#include <sys/types.h>
#include <sys/utsname.h>
#include <sys/wait.h>
@@ -153,6 +154,24 @@
}
}
+// Resets nice priority for zygote process. Zygote priority can be set
+// to high value during boot phase to speed it up. We want to ensure
+// zygote is running at normal priority before childs are forked from it.
+//
+// This ends up being called repeatedly before each fork(), but there's
+// no real harm in that.
+static void ResetNicePriority(JNIEnv* env) {
+ errno = 0;
+ int prio = getpriority(PRIO_PROCESS, 0);
+ if (prio == -1 && errno != 0) {
+ ALOGW("getpriority failed: %s\n", strerror(errno));
+ }
+ if (prio != 0 && setpriority(PRIO_PROCESS, 0, 0) != 0) {
+ ALOGE("setpriority(%d, 0, 0) failed: %s", PRIO_PROCESS, strerror(errno));
+ RuntimeAbort(env, __LINE__, "setpriority failed");
+ }
+}
+
// Sets the SIGCHLD handler back to default behavior in zygote children.
static void UnsetSigChldHandler() {
struct sigaction sa;
@@ -418,27 +437,6 @@
}
}
-#ifdef ENABLE_SCHED_BOOST
-static void SetForkLoad(bool boost) {
- // set scheduler knob to boost forked processes
- pid_t currentPid = getpid();
- // fits at most "/proc/XXXXXXX/sched_init_task_load\0"
- char schedPath[35];
- snprintf(schedPath, sizeof(schedPath), "/proc/%u/sched_init_task_load", currentPid);
- int schedBoostFile = open(schedPath, O_WRONLY);
- if (schedBoostFile < 0) {
- ALOGW("Unable to set zygote scheduler boost");
- return;
- }
- if (boost) {
- write(schedBoostFile, "100\0", 4);
- } else {
- write(schedBoostFile, "0\0", 2);
- }
- close(schedBoostFile);
-}
-#endif
-
// The list of open zygote file descriptors.
static FileDescriptorTable* gOpenFdTable = NULL;
@@ -452,10 +450,6 @@
jstring instructionSet, jstring dataDir) {
SetSigChldHandler();
-#ifdef ENABLE_SCHED_BOOST
- SetForkLoad(true);
-#endif
-
sigset_t sigchld;
sigemptyset(&sigchld);
sigaddset(&sigchld, SIGCHLD);
@@ -486,6 +480,8 @@
RuntimeAbort(env, __LINE__, "Unable to restat file descriptor table.");
}
+ ResetNicePriority(env);
+
pid_t pid = fork();
if (pid == 0) {
@@ -634,11 +630,6 @@
} else if (pid > 0) {
// the parent process
-#ifdef ENABLE_SCHED_BOOST
- // unset scheduler knob
- SetForkLoad(false);
-#endif
-
// We blocked SIGCHLD prior to a fork, we unblock it here.
if (sigprocmask(SIG_UNBLOCK, &sigchld, nullptr) == -1) {
ALOGE("sigprocmask(SIG_SETMASK, { SIGCHLD }) failed: %s", strerror(errno));
@@ -774,4 +765,3 @@
return RegisterMethodsOrDie(env, "com/android/internal/os/Zygote", gMethods, NELEM(gMethods));
}
} // namespace android
-