xnu-7195.81.3.tar.gz

[apple/xnu.git] / iokit / Kernel / IOHibernateIO.cpp

diff --git a/iokit/Kernel/IOHibernateIO.cpp b/iokit/Kernel/IOHibernateIO.cpp
index 1320d8d0cb04efc84f0ce23057ed92b0a759e501..2fc024f6e1fa20b9a78b35e2fca5799c1943d7ee 100644 (file)
--- a/iokit/Kernel/IOHibernateIO.cpp
+++ b/iokit/Kernel/IOHibernateIO.cpp
@@ -201,7 +201,17 @@ static uuid_string_t            gIOHibernateBridgeBootSessionUUIDString;
 
 static uint32_t                 gIOHibernateFreeRatio = 0;       // free page target (percent)
 uint32_t                        gIOHibernateFreeTime  = 0 * 1000;  // max time to spend freeing pages (ms)
-static uint64_t                 gIOHibernateCompression = 0x80;  // default compression 50%
+
+enum {
+       HIB_COMPR_RATIO_ARM64  = (0xa5),  // compression ~65%. Since we don't support retries we start higher.
+       HIB_COMPR_RATIO_INTEL  = (0x80)   // compression 50%
+};
+
+#if defined(__arm64__)
+static uint64_t                 gIOHibernateCompression = HIB_COMPR_RATIO_ARM64;
+#else
+static uint64_t                 gIOHibernateCompression = HIB_COMPR_RATIO_INTEL;
+#endif /* __arm64__ */
 boolean_t                       gIOHibernateStandbyDisabled;
 
 static IODTNVRAM *              gIOOptionsEntry;
@@ -2179,6 +2189,18 @@ hibernate_write_image(void)
                header->sleepTime    = gIOLastSleepTime.tv_sec;
 
                header->compression     = ((uint32_t)((compressedSize << 8) / uncompressedSize));
+#if defined(__arm64__)
+               /*
+                * We don't support retry on hibernation failure and so
+                * we don't want to set this value to anything smaller
+                * just because we may have been lucky this time around.
+                * Though we'll let it go higher.
+                */
+               if (header->compression < HIB_COMPR_RATIO_ARM64) {
+                       header->compression  = HIB_COMPR_RATIO_ARM64;
+               }
+#endif /* __arm64__ */
+
                gIOHibernateCompression = header->compression;
 
                count = vars->fileVars->fileExtents->getLength();