Add support for 32bit allocator flags

Introduce a mechanism to set flags for the 32bit allocator. Use the new mechanism to toggle the vmem mode to tmp file backed vmem. Signed-off-by: Tobi Ajila <atobia@ca.ibm.com>
eclipse · Mar 22, 2024 · 147bfb4 · 147bfb4
1 parent 1bf2ef4
commit 147bfb4
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diff --git a/include_core/omrport.h b/include_core/omrport.h
@@ -885,6 +885,10 @@ typedef struct J9ProcessorInfos {
 #define OMRPORT_CTLDATA_VMEM_PERFORM_FULL_MEMORY_SEARCH  "VMEM_PERFORM_FULL_SEARCH"
 #define OMRPORT_CTLDATA_VMEM_HUGE_PAGES_MMAP_ENABLED "VMEM_HUGE_PAGES_MMAP_ENABLED"
 #define OMRPORT_CTLDATA_CRIU_SUPPORT_FLAGS "CRIU_SUPPORT_FLAGS"
+#define OMRPORT_CTLDATA_MEM_32BIT "MEM_32BIT_FLAGS"
+
+/* OMRPORT_CTLDATA_MEM_32BIT Flags */
+#define OMRPORT_MEM_32BIT_FLAGS_TMP_FILE_BACKED_VMEM 0x1
 
 /* CRIU support is enabled, a checkpoint could be taken
  * if current VM is not from a final restoration.

diff --git a/port/common/omrmem32helpers.c b/port/common/omrmem32helpers.c
@@ -570,6 +570,12 @@ allocateVmemRegion32(struct OMRPortLibrary *portLibrary, uintptr_t byteAmount, J
 		pageSize = 0x1000;
 	}
 
+#if defined(LINUX)
+		if (OMR_ARE_ALL_BITS_SET(PPG_mem32BitFlags, OMRPORT_MEM_32BIT_FLAGS_TMP_FILE_BACKED_VMEM)) {
+			vmemMode |= OMRPORT_VMEM_MEMORY_MODE_SHARE_TMP_FILE_OPEN | OMRPORT_VMEM_MEMORY_MODE_SHARE_FILE_OPEN;
+		}
+#endif /* defined(LINUX) */
+
 	/* iterate through the available regions */
 	for (i = 0; i < sizeof(regions) / sizeof(regions[0]); i++) {
 		J9PortVmemParams params;

diff --git a/port/common/omrportcontrol.c b/port/common/omrportcontrol.c
@@ -326,5 +326,12 @@ omrport_control(struct OMRPortLibrary *portLibrary, const char *key, uintptr_t v
 	}
 #endif /* defined(PPG_criuSupportFlags) */
 
+#if defined(PPG_mem32BitFlags)
+	if (0 == strcmp(OMRPORT_CTLDATA_MEM_32BIT, key)) {
+		PPG_mem32BitFlags = value;
+		return 0;
+	}
+#endif /* defined(PPG_mem32BitFlags) */
+
 	return 1;
 }
diff --git a/port/unix_include/omrportpg.h b/port/unix_include/omrportpg.h
@@ -115,6 +115,7 @@ typedef struct OMRPortPlatformGlobals {
 	int pageProtectionPossible;
 #endif
 	uintptr_t criuSupportFlags;
+	uintptr_t mem32BitFlags;
 } OMRPortPlatformGlobals;
 
 
@@ -178,5 +179,7 @@ typedef struct OMRPortPlatformGlobals {
 
 #define PPG_criuSupportFlags (portLibrary->portGlobals->platformGlobals.criuSupportFlags)
 
+#define PPG_mem32BitFlags (portLibrary->portGlobals->platformGlobals.mem32BitFlags)
+
 #endif /* omrportpg_h */
 
diff --git a/port/zos390/omrportpg.h b/port/zos390/omrportpg.h
@@ -111,4 +111,6 @@ typedef struct OMRPortPlatformGlobals {
 
 #define PPG_criuSupportFlags (portLibrary->portGlobals->platformGlobals.criuSupportFlags)
 
+#define PPG_mem32BitFlags (portLibrary->portGlobals->platformGlobals.mem32BitFlags)
+
 #endif /* omrportpg_h */