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brk(): more forceful heap extension

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This commit is contained in:
Balazs Gerofi
2017-03-06 16:58:11 +09:00
parent e554f4e2f9
commit 0dd2fad33b
4 changed files with 35 additions and 31 deletions
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19
kernel/syscall.c
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@ -1565,27 +1565,36 @@ SYSCALL_DECLARE(brk)
flush_nfo_tlb();
/* brk change fail, including glibc trick brk(0) to obtain current brk */
if(address < region->brk_start) {
if (address < region->brk_start) {
r = region->brk_end;
goto out;
}
/* brk change fail, because we don't shrink memory region */
if(address < region->brk_end) {
if (address < region->brk_end) {
r = region->brk_end;
goto out;
}
/* try to extend memory region */
/* If already allocated, just expand and return */
if (address < region->brk_end_allocated) {
region->brk_end = address;
r = region->brk_end;
goto out;
}
/* Try to extend memory region */
vrflag = VR_PROT_READ | VR_PROT_WRITE;
vrflag |= VRFLAG_PROT_TO_MAXPROT(vrflag);
ihk_mc_spinlock_lock_noirq(&cpu_local_var(current)->vm->memory_range_lock);
region->brk_end = extend_process_region(cpu_local_var(current)->vm,
region->brk_start, region->brk_end, address, vrflag);
region->brk_end_allocated =
extend_process_region(cpu_local_var(current)->vm,
region->brk_end_allocated, address, vrflag);
ihk_mc_spinlock_unlock_noirq(&cpu_local_var(current)->vm->memory_range_lock);
dkprintf("SC(%d)[sys_brk] brk_end set to %lx\n",
ihk_mc_get_processor_id(), region->brk_end);
region->brk_end = address;
r = region->brk_end;
out: