一.先看上层

1.1.  布局 KEY

private static final String SELECT_LOGD_SIZE_KEY = "select_logd_size";

private static final String SELECT_LOGD_SIZE_PROPERTY = "persist.logd.size";

1.2. writeLogdSizeOption()

updateLogpersistValues()

private void writeLogdSizeOption(Object newValue) {

boolean disable = (newValue != null) &&

(newValue.toString().equals(SELECT_LOGD_OFF_SIZE_MARKER_VALUE));

String currentTag = SystemProperties.get(SELECT_LOGD_TAG_PROPERTY);

if (currentTag == null) {

currentTag = "";

}

// filter clean and unstack all references to our setting

String newTag = currentTag.replaceAll(

",+" + SELECT_LOGD_TAG_SILENCE, "").replaceFirst(

"^" + SELECT_LOGD_TAG_SILENCE + ",*", "").replaceAll(

",+", ",").replaceFirst(

",+$", "");

if (disable) {

newValue = SELECT_LOGD_MINIMUM_SIZE_VALUE;

// Make sure snet_event_log get through first, but do not override

String snetValue = SystemProperties.get(SELECT_LOGD_SNET_TAG_PROPERTY);

if ((snetValue == null) || (snetValue.length() == 0)) {

snetValue = SystemProperties.get(SELECT_LOGD_RUNTIME_SNET_TAG_PROPERTY);

if ((snetValue == null) || (snetValue.length() == 0)) {

SystemProperties.set(SELECT_LOGD_SNET_TAG_PROPERTY, "I");

}

}

// Silence all log sources, security logs notwithstanding

if (newTag.length() != 0) {

newTag = "," + newTag;

}

// Stack settings, stack to help preserve original value

newTag = SELECT_LOGD_TAG_SILENCE + newTag;

}

if (!newTag.equals(currentTag)) {

SystemProperties.set(SELECT_LOGD_TAG_PROPERTY, newTag);

}

String defaultValue = defaultLogdSizeValue();

final String size = ((newValue != null) && (newValue.toString().length() != 0)) ?

newValue.toString() : defaultValue;

SystemProperties.set(SELECT_LOGD_SIZE_PROPERTY, defaultValue.equals(size) ? "" : size);

SystemProperties.set("ctl.start", "logd-reinit");

pokeSystemProperties();

updateLogdSizeValues();

}

private void updateLogdSizeValues() {

if (mLogdSize != null) {

String currentTag = SystemProperties.get(SELECT_LOGD_TAG_PROPERTY);

String currentValue = SystemProperties.get(SELECT_LOGD_SIZE_PROPERTY);

if ((currentTag != null) && currentTag.startsWith(SELECT_LOGD_TAG_SILENCE)) {

currentValue = SELECT_LOGD_OFF_SIZE_MARKER_VALUE;

}

if (mLogpersist != null) {

String currentLogpersistEnable

= SystemProperties.get(ACTUAL_LOGPERSIST_PROPERTY_ENABLE);

if ((currentLogpersistEnable == null)

|| !currentLogpersistEnable.equals("true")

|| currentValue.equals(SELECT_LOGD_OFF_SIZE_MARKER_VALUE)) {

writeLogpersistOption(null, true);

mLogpersist.setEnabled(false);

} else if (mLastEnabledState) {

mLogpersist.setEnabled(true);

}

}

if ((currentValue == null) || (currentValue.length() == 0)) {

currentValue = defaultLogdSizeValue();

}

//gatsby 加载res 资源

String[] values = getResources().getStringArray(R.array.select_logd_size_values);

String[] titles = getResources().getStringArray(R.array.select_logd_size_titles);

int index = 2; // punt to second entry if not found

if (SystemProperties.get("ro.config.low_ram").equals("true")) {

mLogdSize.setEntries(R.array.select_logd_size_lowram_titles);

titles = getResources().getStringArray(R.array.select_logd_size_lowram_titles);

index = 1;

}

String[] summaries = getResources().getStringArray(R.array.select_logd_size_summaries);

for (int i = 0; i < titles.length; i++) {

if (currentValue.equals(values[i])

|| currentValue.equals(titles[i])) {

index = i;

break;

}

}

mLogdSize.setValue(values[index]);

mLogdSize.setSummary(summaries[index]);

mLogdSize.setOnPreferenceChangeListener(this);

}

}

二.LogBuffer.cpp

persist.logd.size

persist.logd.size

ro.logd.size

LOG_BUFFER_SIZE, 即256k

LOG_BUFFER_MIN_SIZE, 即64k

三.默认512K

--- a/frameworks/base/packages/SettingsLib/res/values-zh-rCN/arrays.xml

+++ b/frameworks/base/packages/SettingsLib/res/values-zh-rCN/arrays.xml

@@ -62,6 +62,7 @@

"关闭"

"64K"

"256K"

+ "512K"

"1M"

"4M"

"16M"

@@ -76,6 +77,7 @@

"关闭"

"每个日志缓冲区 64K"

"每个日志缓冲区 256K"

+ "每个日志缓冲区 512K"

"每个日志缓冲区 1M"

"每个日志缓冲区 4M"

"每个日志缓冲区 16M"

diff --git a/frameworks/base/packages/SettingsLib/res/values/arrays.xml b/frameworks/base/packages/SettingsLib/res/values/arrays.xml

old mode 100644

new mode 100755

index 920e061..b57115b

--- a/frameworks/base/packages/SettingsLib/res/values/arrays.xml

+++ b/frameworks/base/packages/SettingsLib/res/values/arrays.xml

@@ -122,6 +122,7 @@

32768

65536

+524288

262144

1048576

4194304

diff --git a/system/core/logd/LogBuffer.cpp b/system/core/logd/LogBuffer.cpp

old mode 100644

new mode 100755

index 0497a89..5a2a597

--- a/system/core/logd/LogBuffer.cpp

+++ b/system/core/logd/LogBuffer.cpp

@@ -97,14 +97,20 @@ void LogBuffer::init() {

static const char global_tuneable[] = "persist.logd.size"; // Settings App

static const char global_default[] = "ro.logd.size"; // BoardConfig.mk

+SLOGE("gatsby LogBuffer init");

+

unsigned long default_size = property_get_size(global_tuneable);

+SLOGE("000 gatsby default_size -> %lu .",default_size);

if (!default_size) {

+SLOGE("000 gatsby !!!default_size aaa -> %lu .",default_size);

default_size = property_get_size(global_default);

+SLOGE("000 gatsby !!!default_size bbb -> %lu .",default_size);

if (!default_size) {

default_size = property_get_bool("ro.config.low_ram",

BOOL_DEFAULT_FALSE)

? LOG_BUFFER_MIN_SIZE // 64K

: LOG_BUFFER_SIZE; // 256K

+SLOGE("000 gatsby !!!!!default_size ccc -> %lu .",default_size);

}

}

@@ -116,24 +122,32 @@ void LogBuffer::init() {

snprintf(key, sizeof(key), "%s.%s",

global_tuneable, android_log_id_to_name(i));

+//getprop persist.logd.size

unsigned long property_size = property_get_size(key);

if (!property_size) {

snprintf(key, sizeof(key), "%s.%s",

global_default, android_log_id_to_name(i));

property_size = property_get_size(key);

+SLOGE("111 gatsby global_tuneable -> %s . android_log_id_to_name(i) -> %s .",global_tuneable,android_log_id_to_name(i));

+SLOGE("111 gatsby property_size -> %lu .",property_size);

}

if (!property_size) {

property_size = default_size;

+SLOGE("2222 gatsby property_size -> %lu .",property_size);

}

if (!property_size) {

+//256k

property_size = LOG_BUFFER_SIZE;

+SLOGE("333 gatsby property_size -> %lu .",property_size);

}

if (setSize(i, property_size)) {

+//64k

setSize(i, LOG_BUFFER_MIN_SIZE);

+SLOGE("444 gatsby property_size -> %lu .",property_size);

}

}

bool lastMonotonic = monotonic;