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Changed pagefault delivery to VM

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this patch changes the way pagefaults are delivered to VM. It adopts
the same model as the out-of-quantum messages sent by kernel to a
scheduler.

- everytime a userspace pagefault occurs, kernel creates a message
  which is sent to VM on behalf of the faulting process

- the process is blocked on delivery to VM in the standard IPC code
  instead of waiting in a spacial in-kernel queue (stack) and is not
  runnable until VM tell kernel that the pagefault is resolved and is
  free to clear the RTS_PAGEFAULT flag.

- VM does not need call kernel and poll the pagefault information
  which saves many (1/2?) calls and kernel calls that return "no more
  data"

- VM notification by kernel does not need to use signals

- each entry in proc table is by 12 bytes smaller (~3k save)
This commit is contained in:
Tomas Hruby
2010-04-26 23:21:26 +00:00
parent a131085a5b
commit f51eea4b32
13 changed files with 104 additions and 178 deletions
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10
include/arch/i386/archtypes.h
View File

@@ -28,16 +28,6 @@ typedef struct segframe {
struct segdesc_s p_ldt[LDT_SIZE]; /* CS, DS and remote */
} segframe_t;
/* Page fault event. Stored in process table. Only valid if PAGEFAULT
* set in p_rts_flags.
*/
struct pagefault
{
u32_t pf_virtual; /* Address causing fault (CR2). */
u32_t pf_flags; /* Pagefault flags on stack. */
};
/* fpu_state_s is used in kernel proc table.
* Any changes in this structure requires changes in sconst.h,
* since this structure is used in proc structure. */

6
include/minix/com.h
View File

@@ -614,7 +614,6 @@
/* Values for SVMCTL_PARAM. */
#define VMCTL_I386_SETCR3 10
#define VMCTL_GET_PAGEFAULT 11
#define VMCTL_CLEAR_PAGEFAULT 12
#define VMCTL_I386_GETCR3 13
#define VMCTL_MEMREQ_GET 14
@@ -1018,6 +1017,11 @@
#define NR_VM_CALLS 42
#define VM_CALL_MASK_SIZE BITMAP_CHUNKS(NR_VM_CALLS)
/* not handled as a normal VM call, thus at the end of the reserved rage */
#define VM_PAGEFAULT (VM_RQ_BASE+0xff)
# define VPF_ADDR m1_i1
# define VPF_FLAGS m1_i2
/* Basic vm calls allowed to every process. */
#define VM_BASIC_CALLS \
VM_MMAP, VM_MUNMAP, VM_MUNMAP_TEXT, VM_MAP_PHYS, VM_UNMAP_PHYS

11
include/signal.h
View File

@@ -75,13 +75,12 @@ typedef unsigned long sigset_t;
#define IS_SIGS(signo) (signo>=SIGS_FIRST && signo<=SIGS_LAST)
/* Signals delivered by the kernel. */
#define SIGKPF 27 /* kernel page fault request pending */
#define SIGKMEM 28 /* kernel memory request pending */
#define SIGKMESS 29 /* new kernel message */
#define SIGKSIGSM 30 /* kernel signal pending for signal manager */
#define SIGKSIG 31 /* kernel signal pending */
#define SIGKMEM 27 /* kernel memory request pending */
#define SIGKMESS 28 /* new kernel message */
#define SIGKSIGSM 29 /* kernel signal pending for signal manager */
#define SIGKSIG 30 /* kernel signal pending */
#define SIGK_FIRST SIGKPF /* first kernel signal */
#define SIGK_FIRST SIGKMEM /* first kernel signal */
#define SIGK_LAST SIGKSIG /* last kernel signal */
#define IS_SIGK(signo) (signo>=SIGK_FIRST && signo<=SIGK_LAST)