log: Allow setting maximum log level higher than default

Main change is possibility the log cache locking functions will
be called before the scheduler has started.

This change doesn't change the behaviour of ESP_EARLY_LOGx, this is
done in the following commit.

Closes https://github.com/espressif/esp-idf/issues/5542

components/log/log_freertos.c

@@ -11,11 +11,16 @@
 #include "freertos/task.h"
 #include "freertos/semphr.h"
 #include "hal/cpu_hal.h" // for cpu_hal_get_cycle_count()
+#include "esp_compiler.h"
 #include "esp_log.h"
 #include "esp_log_private.h"
 
 
 // Maximum time to wait for the mutex in a logging statement.
+//
+// We don't expect this to happen in most cases, as contention is low. The most likely case is if a
+// log function is called from an ISR (technically caller should use the ISR-friendly logging macros but
+// possible they use the normal one instead and disable the log type by tag).
 #define MAX_MUTEX_WAIT_MS 10
 #define MAX_MUTEX_WAIT_TICKS ((MAX_MUTEX_WAIT_MS + portTICK_PERIOD_MS - 1) / portTICK_PERIOD_MS)
 
@@ -23,22 +28,31 @@ static SemaphoreHandle_t s_log_mutex = NULL;
 
 void esp_log_impl_lock(void)
 {
-    if (!s_log_mutex) {
+    if (unlikely(!s_log_mutex)) {
         s_log_mutex = xSemaphoreCreateMutex();
     }
+    if (unlikely(xTaskGetSchedulerState() == taskSCHEDULER_NOT_STARTED)) {
+        return;
+    }
     xSemaphoreTake(s_log_mutex, portMAX_DELAY);
 }
 
 bool esp_log_impl_lock_timeout(void)
 {
-    if (!s_log_mutex) {
+    if (unlikely(!s_log_mutex)) {
         s_log_mutex = xSemaphoreCreateMutex();
     }
+    if (unlikely(xTaskGetSchedulerState() == taskSCHEDULER_NOT_STARTED)) {
+        return true;
+    }
     return xSemaphoreTake(s_log_mutex, MAX_MUTEX_WAIT_TICKS) == pdTRUE;
 }
 
 void esp_log_impl_unlock(void)
 {
+    if (unlikely(xTaskGetSchedulerState() == taskSCHEDULER_NOT_STARTED)) {
+        return;
+    }
     xSemaphoreGive(s_log_mutex);
 }
 
@@ -84,7 +98,7 @@ char *esp_log_system_timestamp(void)
 
 uint32_t esp_log_timestamp(void)
 {
-    if (xTaskGetSchedulerState() == taskSCHEDULER_NOT_STARTED) {
+    if (unlikely(xTaskGetSchedulerState() == taskSCHEDULER_NOT_STARTED)) {
         return esp_log_early_timestamp();
     }
     static uint32_t base = 0;