From 4e62de64cd3b8b67bdb2c3d8edab1ca353427a84 Mon Sep 17 00:00:00 2001 From: Robert Morris Date: Thu, 25 Jul 2019 06:30:49 -0400 Subject: fix an exit/exit deadlock -> one more locking protocol violation increase timer rate from 1/second to 10/second --- kernel/start.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'kernel/start.c') diff --git a/kernel/start.c b/kernel/start.c index 6dc106d..d1fc9c6 100644 --- a/kernel/start.c +++ b/kernel/start.c @@ -41,15 +41,16 @@ start() // which turns them into software interrupts for // devintr() in trap.c. int id = r_mhartid(); - // ask the CLINT for a timer interrupt 10,000 cycles from now. - *(uint64*)CLINT_MTIMECMP(id) = *(uint64*)CLINT_MTIME + 10000; + // ask the CLINT for a timer interrupt. + int interval = 1000000; // cycles; about 1/10th second in qemu. + *(uint64*)CLINT_MTIMECMP(id) = *(uint64*)CLINT_MTIME + interval; // prepare information in scratch[] for machinevec. // scratch[0..3] : space for machinevec to save registers. // scratch[4] : address of CLINT MTIMECMP register. // scratch[5] : desired interval (in cycles) between timer interrupts. uint64 *scratch = &mscratch0[32 * id]; scratch[4] = CLINT_MTIMECMP(id); - scratch[5] = 10000000; + scratch[5] = interval; w_mscratch((uint64)scratch); // set the machine-mode trap handler. w_mtvec((uint64)machinevec); @@ -61,6 +62,6 @@ start() // keep each CPU's hartid in its tp register, for cpuid(). w_tp(id); - // call main() in supervisor mode. + // switch to supervisor mode and jump to main(). asm volatile("mret"); } -- cgit v1.2.3