dm: use hugetlb by default

use hugetlb to set vm memory by default.

Signed-off-by: Li, Fei1 <fei1.li@intel.com>

devicemodel/core/main.c

@@ -72,7 +72,6 @@ char *guest_uuid_str;
 char *vsbl_file_name;
 uint8_t trusty_enabled;
 bool stdio_in_use;
-bool hugetlb;
 
 static int guest_vmexit_on_hlt, guest_vmexit_on_pause;
 static int virtio_msix = 1;
@@ -145,7 +144,6 @@ usage(int code)
 		"       -U: uuid\n"
 		"       -w: ignore unimplemented MSRs\n"
 		"       -W: force virtio to use single-vector MSI\n"
-		"       -T: use hugetlb for memory allocation\n"
 		"       -x: local apic is in x2APIC mode\n"
 		"       -Y: disable MPtable generation\n"
 		"       -k: kernel image path\n"
@@ -649,14 +647,13 @@ main(int argc, char *argv[])
 	mptgen = 1;
 	memflags = 0;
 	quit_vm_loop = 0;
-	hugetlb = 0;
 
 	if (signal(SIGHUP, sig_handler_term) == SIG_ERR)
 		fprintf(stderr, "cannot register handler for SIGHUP\n");
 	if (signal(SIGINT, sig_handler_term) == SIG_ERR)
 		fprintf(stderr, "cannot register handler for SIGINT\n");
 
-	optstr = "abehuwxACHIPSTWYvk:r:B:p:g:c:s:m:l:U:G:i:";
+	optstr = "abehuwxACHIPSWYvk:r:B:p:g:c:s:m:l:U:G:i:";
 	while ((c = getopt_long(argc, argv, optstr, long_options,
 			&option_idx)) != -1) {
 		switch (c) {
@@ -740,10 +737,6 @@ main(int argc, char *argv[])
 		case 'W':
 			virtio_msix = 0;
 			break;
-		case 'T':
-			if (check_hugetlb_support())
-				hugetlb = 1;
-			break;
 		case 'x':
 			x2apic_mode = 1;
 			break;
@@ -807,6 +800,11 @@ main(int argc, char *argv[])
 	if (argc != 1)
 		usage(1);
 
+	if (!check_hugetlb_support()) {
+		fprintf(stderr, "check_hugetlb_support failed\n");
+		exit(1);
+	}
+
 	vmname = argv[0];
 
 	for (;;) {

devicemodel/core/vmmapi.c

@@ -385,8 +385,7 @@ vm_setup_memory(struct vmctx *ctx, size_t memsize, enum vm_mmap_style vms)
 		objsize = ctx->lowmem;
 	}
 
-	if (hugetlb)
-		return hugetlb_setup_memory(ctx);
+	return hugetlb_setup_memory(ctx);
 
 	/*
 	 * Stake out a contiguous region covering the guest physical memory
@@ -431,10 +430,8 @@ vm_setup_memory(struct vmctx *ctx, size_t memsize, enum vm_mmap_style vms)
 void
 vm_unsetup_memory(struct vmctx *ctx)
 {
-	if (hugetlb) {
-		hugetlb_unsetup_memory(ctx);
-		return;
-	}
+	hugetlb_unsetup_memory(ctx);
+	return;
 
 	if (ctx->lowmem > 0)
 		munmap(ctx->mmap_lowmem, ctx->lowmem);

devicemodel/include/vmmapi.h

@@ -159,6 +159,4 @@ int	vm_reset_ptdev_intx_info(struct vmctx *ctx, int virt_pin, bool pic_pin);
 int	vm_create_vcpu(struct vmctx *ctx, uint16_t vcpu_id);
 
 int	vm_get_cpu_state(struct vmctx *ctx, void *state_buf);
-
-extern bool hugetlb;
 #endif	/* _VMMAPI_H_ */

devicemodel/samples/apl-mrb/launch_uos.sh

@@ -107,7 +107,7 @@ else
 fi
 
 
-acrn-dm -T -A -m $mem_size -c $2$boot_GVT_option"$GVT_args" -s 0:0,hostbridge -s 1:0,lpc -l com1,stdio \
+acrn-dm -A -m $mem_size -c $2$boot_GVT_option"$GVT_args" -s 0:0,hostbridge -s 1:0,lpc -l com1,stdio \
   -s 5,virtio-console,@pty:pty_port \
   -s 6,virtio-hyper_dmabuf \
   -s 8,wdt-i6300esb \
@@ -274,7 +274,7 @@ else
   GVT_args=''
 fi
 
- acrn-dm -T -A -m $mem_size -c $2$boot_GVT_option"$GVT_args" -s 0:0,hostbridge -s 1:0,lpc -l com1,stdio \
+ acrn-dm -A -m $mem_size -c $2$boot_GVT_option"$GVT_args" -s 0:0,hostbridge -s 1:0,lpc -l com1,stdio \
    -l com1,stdio \
    -s 9,virtio-net,$tap \
    -s 3,virtio-blk$boot_dev_flag,/data/$5/$5.img \

devicemodel/samples/nuc/launch_uos.sh

@@ -19,7 +19,7 @@ mem_size=1000M
 # make sure there is enough 2M hugepages in the pool
 echo 1024 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
 
-acrn-dm -T -A -m $mem_size -c $2 -s 0:0,hostbridge -s 1:0,lpc -l com1,stdio \
+acrn-dm -A -m $mem_size -c $2 -s 0:0,hostbridge -s 1:0,lpc -l com1,stdio \
   -s 2,pci-gvt -G "$3" \
   -s 5,virtio-console,@pty:pty_port \
   -s 6,virtio-hyper_dmabuf \

doc/getting_started/index.rst

@@ -330,38 +330,26 @@ Set up Reference UOS
 Device Manager memory allocation mechanism
 ==========================================
 
-There are two Device Manager memory allocation mechanisms available:
+The ACRN Device Manager (DM) virtual memory allocation uses the HugeTLB mechanism.
+(You can read more about `HugeTLB in the linux kernel <https://linuxgazette.net/155/krishnakumar.html>`_
+for more information about how this mechanism works.)
 
-- Contiguous Memory Allocator (CMA), and 
-- Huge Page Tables (HugeTLB).  HugeTLB is the default.
+For hugeTLB to work, you'll need to reserve huge pages:
 
-To choose CMA, do the following:
+  - For a (large) 1GB huge page reservation, add ``hugepagesz=1G hugepages=reserved_pg_num``
+    (for example, ``hugepagesz=1G hugepages=4``) to the SOS cmdline in
+    ``acrn.conf`` (for EFI)
 
-1) Add ``cma=reserved_mem_size@recommend_memory_offset-0``, (for example
-   ``cma=2560M@0x100000000-0``) to the SOS cmdline in ``acrn.conf``
+  - For a (smaller) 2MB huge page reservation, after the SOS starts up, run the
+    command::
 
-2) Start ``acrn-dm`` *without* the ``-T`` option
+       echo reserved_pg_num > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
 
-To support HugeTLB, do the following:
-
-1) Do huge page reservation
-
-   - For 1G huge page reservation, add ``hugepagesz=1G hugepages=reserved_pg_num``
-     (for example, ``hugepagesz=1G hugepages=4``) to the SOS cmdline in
-     ``acrn.conf`` (for EFI)
-
-   - For 2M huge page reservation, after the SOS starts up, run the
-     command::
-
-        echo reserved_pg_num > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
-
-   .. note::
-      You can use 2M reserving method to do reservation for 1G page size, but it
-      may fail.  For an EFI platform, you may skip 1G page reservation
-      by using a 2M page, but make sure your huge page reservation size is
-      large enough for your usage.
-
-2)  Start ``acrn-dm`` *with* the ``-T`` option.
+  .. note::
+     You can use 2M reserving method to do reservation for 1G page size, but it
+     may fail.  For an EFI platform, you may skip 1G page reservation
+     by using a 2M page, but make sure your huge page reservation size is
+     large enough for your usage.
 
 Build ACRN from Source
 **********************