* [Linux-ia64] Preemption patch against ~2.5.60
@ 2003-02-14 4:16 Peter Chubb
0 siblings, 0 replies; only message in thread
From: Peter Chubb @ 2003-02-14 4:16 UTC (permalink / raw)
To: linux-ia64
[-- Attachment #1: message body text --]
[-- Type: text/plain, Size: 41 bytes --]
OK, here's the latest preemption patch.
[-- Attachment #2: ia64-2.5.60-preempt.patch --]
[-- Type: text/plain, Size: 27549 bytes --]
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/arch/ia64/Kconfig linux-2.5-preempt/arch/ia64/Kconfig
--- linux-2.5-EXPORT/arch/ia64/Kconfig Thu Feb 13 13:26:52 2003
+++ linux-2.5-preempt/arch/ia64/Kconfig Thu Feb 13 13:57:07 2003
@@ -424,6 +424,18 @@
If you don't know what to do here, say N.
+config PREEMPT
+ bool "Preemptible Kernel"
+ help
+ This option reduces the latency of the kernel when reacting to
+ real-time or interactive events by allowing a low priority process to
+ be preempted even if it is in kernel mode executing a system call.
+ This allows applications to run more reliably even when the system is
+ under load.
+
+ Say Y here if you are building a kernel for a desktop, embedded
+ or real-time system. Say N if you are unsure.
+
config IA32_SUPPORT
bool "Support running of Linux/x86 binaries"
help
@@ -874,6 +886,12 @@
and certain other kinds of spinlock errors commonly made. This is
best used in conjunction with the NMI watchdog so that spinlock
deadlocks are also debuggable.
+
+config DEBUG_SPINLOCK_SLEEP
+ bool "Sleep-inside-spinlock checking"
+ help
+ If you say Y here, various routines which may sleep will become very
+ noisy if they are called with a spinlock held.
config IA64_DEBUG_CMPXCHG
bool "Turn on compare-and-exchange bug checking (slow!)"
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/arch/ia64/hp/sim/simserial.c linux-2.5-preempt/arch/ia64/hp/sim/simserial.c
--- linux-2.5-EXPORT/arch/ia64/hp/sim/simserial.c Mon Feb 10 10:20:14 2003
+++ linux-2.5-preempt/arch/ia64/hp/sim/simserial.c Thu Feb 13 13:43:47 2003
@@ -63,7 +63,6 @@
static char *serial_name = "SimSerial driver";
static char *serial_version = "0.6";
-static spinlock_t serial_lock = SPIN_LOCK_UNLOCKED;
/*
* This has been extracted from asm/serial.h. We need one eventually but
@@ -235,14 +234,14 @@
if (!tty || !info->xmit.buf) return;
- spin_lock_irqsave(&serial_lock, flags);
+ local_irq_save(flags);
if (CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE) == 0) {
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
return;
}
info->xmit.buf[info->xmit.head] = ch;
info->xmit.head = (info->xmit.head + 1) & (SERIAL_XMIT_SIZE-1);
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
}
static _INLINE_ void transmit_chars(struct async_struct *info, int *intr_done)
@@ -250,7 +249,8 @@
int count;
unsigned long flags;
- spin_lock_irqsave(&serial_lock, flags);
+
+ local_irq_save(flags);
if (info->x_char) {
char c = info->x_char;
@@ -293,7 +293,7 @@
info->xmit.tail += count;
}
out:
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
}
static void rs_flush_chars(struct tty_struct *tty)
@@ -334,7 +334,7 @@
break;
}
- spin_lock_irqsave(&serial_lock, flags);
+ local_irq_save(flags);
{
c1 = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail,
SERIAL_XMIT_SIZE);
@@ -344,7 +344,7 @@
info->xmit.head = ((info->xmit.head + c) &
(SERIAL_XMIT_SIZE-1));
}
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
buf += c;
count -= c;
@@ -352,7 +352,7 @@
}
up(&tmp_buf_sem);
} else {
- spin_lock_irqsave(&serial_lock, flags);
+ local_irq_save(flags);
while (1) {
c = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
if (count < c)
@@ -367,7 +367,7 @@
count -= c;
ret += c;
}
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
}
/*
* Hey, we transmit directly from here in our case
@@ -398,9 +398,9 @@
struct async_struct *info = (struct async_struct *)tty->driver_data;
unsigned long flags;
- spin_lock_irqsave(&serial_lock, flags);
+ local_irq_save(flags);
info->xmit.head = info->xmit.tail = 0;
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
wake_up_interruptible(&tty->write_wait);
@@ -573,7 +573,7 @@
state->irq);
#endif
- spin_lock_irqsave(&serial_lock, flags);
+ local_irq_save(flags);
{
/*
* First unlink the serial port from the IRQ chain...
@@ -611,7 +611,7 @@
info->flags &= ~ASYNC_INITIALIZED;
}
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
}
/*
@@ -634,13 +634,13 @@
state = info->state;
- spin_lock_irqsave(&serial_lock, flags);
+ local_irq_save(flags);
if (tty_hung_up_p(filp)) {
#ifdef SIMSERIAL_DEBUG
printk("rs_close: hung_up\n");
#endif
MOD_DEC_USE_COUNT;
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
return;
}
#ifdef SIMSERIAL_DEBUG
@@ -665,11 +665,11 @@
}
if (state->count) {
MOD_DEC_USE_COUNT;
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
return;
}
info->flags |= ASYNC_CLOSING;
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
/*
* Now we wait for the transmit buffer to clear; and we notify
@@ -776,7 +776,7 @@
if (!page)
return -ENOMEM;
- spin_lock_irqsave(&serial_lock, flags);
+ local_irq_save(flags);
if (info->flags & ASYNC_INITIALIZED) {
free_page(page);
@@ -857,11 +857,11 @@
}
info->flags |= ASYNC_INITIALIZED;
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
return 0;
errout:
- spin_unlock_irqrestore(&serial_lock, flags);
+ local_irq_restore(flags);
return retval;
}
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/arch/ia64/ia32/ia32_support.c linux-2.5-preempt/arch/ia64/ia32/ia32_support.c
--- linux-2.5-EXPORT/arch/ia64/ia32/ia32_support.c Wed Jan 29 13:55:00 2003
+++ linux-2.5-preempt/arch/ia64/ia32/ia32_support.c Thu Jan 30 14:14:13 2003
@@ -93,7 +93,7 @@
{
unsigned long eflag, fsr, fcr, fir, fdr, csd, ssd, tssd;
struct pt_regs *regs = ia64_task_regs(t);
- int nr = smp_processor_id(); /* LDT and TSS depend on CPU number: */
+ int nr = get_cpu(); /* LDT and TSS depend on CPU number: */
eflag = t->thread.eflag;
fsr = t->thread.fsr;
@@ -119,6 +119,7 @@
regs->r17 = (_TSS(nr) << 48) | (_LDT(nr) << 32) | (__u32) regs->r17;
regs->r30 = load_desc(_LDT(nr)); /* LDTD */
+ put_cpu();
}
/*
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/arch/ia64/kernel/entry.S linux-2.5-preempt/arch/ia64/kernel/entry.S
--- linux-2.5-EXPORT/arch/ia64/kernel/entry.S Thu Feb 13 13:26:52 2003
+++ linux-2.5-preempt/arch/ia64/kernel/entry.S Thu Feb 13 13:43:47 2003
@@ -586,10 +586,21 @@
// work.need_resched etc. mustn't get changed by this CPU before it returns to
// user- or fsys-mode:
(pUStk) cmp.eq.unc p6,p0=r0,r0 // p6 <- pUStk
+#ifdef CONFIG_PREEMPT
+ rsm psr.i // disable interrupts
+ adds r17=TI_FLAGS+IA64_TASK_SIZE,r13
+(pKStk) adds r20=TI_PRE_COUNT+IA64_TASK_SIZE,r13
+ ;;
+(pKStk) ld4 r21=[r20] // preempt_count ->r21
+ ;;
+(pKStk) cmp4.eq p6,p0=r21,r0 // p6 <- preempt_count == 0
+ ;;
+#else // CONFIG_PREEMPT
(pUStk) rsm psr.i
;;
(pUStk) adds r17=TI_FLAGS+IA64_TASK_SIZE,r13
;;
+#endif // CONFIG_PREEMPT
.work_processed:
(p6) ld4 r18=[r17] // load current_thread_info()->flags
adds r2=PT(R8)+16,r12
@@ -810,15 +821,27 @@
.work_pending:
tbit.z p6,p0=r18,TIF_NEED_RESCHED // current_thread_info()->need_resched==0?
(p6) br.cond.sptk.few .notify
+#ifdef CONFIG_PREEMPT
+(pKStk) dep r21=-1,r0,PREEMPT_ACTIVE_BIT,1
+ ;;
+(pKStk) st4 [r20]=r21
+ ssm psr.i // enable interrupts
+#endif
+
#if __GNUC__ < 3
br.call.spnt.many rp=invoke_schedule
#else
br.call.spnt.many rp=schedule
#endif
.ret9: cmp.eq p6,p0=r0,r0 // p6 <- 1
- rsm psr.i
+ rsm psr.i // disable interrupts
;;
adds r17=TI_FLAGS+IA64_TASK_SIZE,r13
+#if CONFIG_PREEMPT
+(pKStk) adds r20=TI_PRE_COUNT+IA64_TASK_SIZE,r13
+ ;;
+(pKStk) st4 [r20]=r0 // preempt_count() <- 0
+#endif
br.cond.sptk.many .work_processed // re-check
.notify:
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/arch/ia64/kernel/irq.c linux-2.5-preempt/arch/ia64/kernel/irq.c
--- linux-2.5-EXPORT/arch/ia64/kernel/irq.c Mon Feb 10 10:20:14 2003
+++ linux-2.5-preempt/arch/ia64/kernel/irq.c Thu Feb 13 13:43:47 2003
@@ -340,12 +340,14 @@
* 0 return value means that this irq is already being
* handled by some other CPU. (or is disabled)
*/
- int cpu = smp_processor_id();
+ int cpu;
irq_desc_t *desc = irq_desc(irq);
struct irqaction * action;
unsigned int status;
irq_enter();
+ cpu = smp_processor_id();
+
kstat_cpu(cpu).irqs[irq]++;
if (desc->status & IRQ_PER_CPU) {
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/arch/ia64/kernel/palinfo.c linux-2.5-preempt/arch/ia64/kernel/palinfo.c
--- linux-2.5-EXPORT/arch/ia64/kernel/palinfo.c Mon Feb 10 10:20:14 2003
+++ linux-2.5-preempt/arch/ia64/kernel/palinfo.c Thu Feb 13 13:43:47 2003
@@ -894,10 +894,12 @@
* in SMP mode, we may need to call another CPU to get correct
* information. PAL, by definition, is processor specific
*/
- if (f->req_cpu == smp_processor_id())
+ if (f->req_cpu == get_cpu())
len = (*palinfo_entries[f->func_id].proc_read)(page);
else
len = palinfo_handle_smp(f, page);
+
+ put_cpu();
if (len <= off+count) *eof = 1;
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/arch/ia64/kernel/perfmon.c linux-2.5-preempt/arch/ia64/kernel/perfmon.c
--- linux-2.5-EXPORT/arch/ia64/kernel/perfmon.c Thu Feb 13 13:26:52 2003
+++ linux-2.5-preempt/arch/ia64/kernel/perfmon.c Fri Feb 14 14:43:03 2003
@@ -1523,6 +1523,7 @@
* Cannot do anything before PMU is enabled
*/
if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
+ preempt_disable();
/* XXX: ctx locking may be required here */
@@ -1599,10 +1600,12 @@
ctx->ctx_used_pmds[0],
ctx->ctx_soft_pmds[cnum].reset_pmds[0]));
}
-
+ preempt_enable();
return 0;
abort_mission:
+ preempt_enable();
+
/*
* for now, we have only one possibility for error
*/
@@ -1647,6 +1650,7 @@
DBprintk(("ctx_last_cpu=%d for [%d]\n", atomic_read(&ctx->ctx_last_cpu), task->pid));
for (i = 0; i < count; i++, req++) {
+ int me;
#if __GNUC__ < 3
foo = __get_user(cnum, &req->reg_num);
if (foo) return -EFAULT;
@@ -1674,13 +1678,16 @@
* PMU state is still in the local live register due to lazy ctxsw.
* If true, then we read directly from the registers.
*/
- if (atomic_read(&ctx->ctx_last_cpu) == smp_processor_id()){
+ me = get_cpu();
+ if (atomic_read(&ctx->ctx_last_cpu) == me){
ia64_srlz_d();
val = ia64_get_pmd(cnum);
DBprintk(("reading pmd[%u]=0x%lx from hw\n", cnum, val));
} else {
val = th->pmd[cnum];
}
+
+
if (PMD_IS_COUNTING(cnum)) {
/*
* XXX: need to check for overflow
@@ -1702,6 +1709,8 @@
PFM_REG_RETFLAG_SET(reg_flags, ret);
+ put_cpu();
+
DBprintk(("read pmd[%u] ret=%d value=0x%lx pmc=0x%lx\n",
cnum, ret, val, ia64_get_pmc(cnum)));
@@ -1839,6 +1848,7 @@
ctx->ctx_fl_frozen,
ctx->ctx_ovfl_regs[0]));
+ preempt_disable();
pfm_reset_regs(ctx, ctx->ctx_ovfl_regs, PFM_PMD_LONG_RESET);
ctx->ctx_ovfl_regs[0] = 0UL;
@@ -1857,6 +1867,8 @@
/* simply unfreeze */
pfm_unfreeze_pmu();
+ preempt_enable();
+
return 0;
}
/* restart on another task */
@@ -1914,6 +1926,7 @@
ctx->ctx_fl_system, PMU_OWNER(),
current));
+ preempt_disable();
/* simply stop monitoring but not the PMU */
if (ctx->ctx_fl_system) {
@@ -1941,6 +1954,7 @@
*/
ia64_psr(regs)->up = 0;
}
+ preempt_enable();
return 0;
}
@@ -1953,6 +1967,7 @@
if (!CTX_IS_ENABLED(ctx)) return -EINVAL;
+ preempt_disable();
/*
* stop monitoring, freeze PMU, and save state in context
* this call will clear IA64_THREAD_PM_VALID for per-task sessions.
@@ -1973,6 +1988,7 @@
DBprintk(("enabling psr.sp for [%d]\n", current->pid));
ctx->ctx_flags.state = PFM_CTX_DISABLED;
+ preempt_enable();
return 0;
}
@@ -2322,6 +2338,7 @@
return -EINVAL;
}
+ preempt_disable();
if (ctx->ctx_fl_system) {
PFM_CPUINFO_SET(PFM_CPUINFO_DCR_PP);
@@ -2339,6 +2356,7 @@
} else {
if ((task->thread.flags & IA64_THREAD_PM_VALID) == 0) {
+ preempt_enable();
printk(KERN_DEBUG "perfmon: pfm_start task flag not set for [%d]\n",
task->pid);
return -EINVAL;
@@ -2352,6 +2370,7 @@
ia64_srlz_i();
}
+ preempt_enable();
return 0;
}
@@ -2359,9 +2378,13 @@
pfm_enable(struct task_struct *task, pfm_context_t *ctx, void *arg, int count,
struct pt_regs *regs)
{
+ int me;
+
/* we don't quite support this right now */
if (task != current) return -EINVAL;
+ me = get_cpu(); /* make sure we're not migrated or preempted */
+
if (ctx->ctx_fl_system == 0 && PMU_OWNER() && PMU_OWNER() != current)
pfm_lazy_save_regs(PMU_OWNER());
@@ -2405,11 +2428,13 @@
SET_PMU_OWNER(task);
ctx->ctx_flags.state = PFM_CTX_ENABLED;
- atomic_set(&ctx->ctx_last_cpu, smp_processor_id());
+ atomic_set(&ctx->ctx_last_cpu, me);
/* simply unfreeze */
pfm_unfreeze_pmu();
+ put_cpu();
+
return 0;
}
@@ -2826,7 +2851,7 @@
* initialize entry header
*/
h->pid = current->pid;
- h->cpu = smp_processor_id();
+ h->cpu = get_cpu();
h->last_reset_value = ovfl_mask ? ctx->ctx_soft_pmds[ffz(~ovfl_mask)].lval : 0UL;
h->ip = regs ? regs->cr_iip | ((regs->cr_ipsr >> 41) & 0x3): 0x0UL;
h->regs = ovfl_mask; /* which registers overflowed */
@@ -2853,7 +2878,7 @@
DBprintk_ovfl(("e=%p pmd%d =0x%lx\n", (void *)e, j, *e));
e++;
}
- pfm_stats[smp_processor_id()].pfm_recorded_samples_count++;
+ pfm_stats[h->cpu].pfm_recorded_samples_count++;
/*
* make the new entry visible to user, needs to be atomic
@@ -2870,9 +2895,11 @@
/*
* XXX: must reset buffer in blocking mode and lost notified
*/
- pfm_stats[smp_processor_id()].pfm_full_smpl_buffer_count++;
+ pfm_stats[h->cpu].pfm_full_smpl_buffer_count++;
+ put_cpu();
return 1;
}
+ put_cpu();
return 0;
}
@@ -2904,6 +2931,8 @@
* valid one, i.e. the one that caused the interrupt.
*/
+ preempt_disable();
+
t = &task->thread;
/*
@@ -2913,6 +2942,7 @@
if ((t->flags & IA64_THREAD_PM_VALID) == 0 && ctx->ctx_fl_system == 0) {
printk(KERN_DEBUG "perfmon: Spurious overflow interrupt: process %d not "
"using perfmon\n", task->pid);
+ preempt_enable_no_resched();
return 0x1;
}
/*
@@ -2921,6 +2951,7 @@
if ((pmc0 & 0x1) == 0) {
printk(KERN_DEBUG "perfmon: pid %d pmc0=0x%lx assumption error for freeze bit\n",
task->pid, pmc0);
+ preempt_enable_no_resched();
return 0x0;
}
@@ -3003,6 +3034,7 @@
if (ovfl_notify == 0UL) {
if (ovfl_pmds)
pfm_reset_regs(ctx, &ovfl_pmds, PFM_PMD_SHORT_RESET);
+ preempt_enable_no_resched();
return 0x0UL;
}
@@ -3038,6 +3070,7 @@
t->pfm_ovfl_block_reset,
ctx->ctx_fl_trap_reason));
+ preempt_enable_no_resched();
return 0x1UL;
}
@@ -3048,13 +3081,14 @@
struct task_struct *task;
pfm_context_t *ctx;
- pfm_stats[smp_processor_id()].pfm_ovfl_intr_count++;
+ pfm_stats[get_cpu()].pfm_ovfl_intr_count++;
/*
* if an alternate handler is registered, just bypass the default one
*/
if (pfm_alternate_intr_handler) {
(*pfm_alternate_intr_handler->handler)(irq, arg, regs);
+ put_cpu();
return;
}
@@ -3079,6 +3113,7 @@
if (!ctx) {
printk(KERN_DEBUG "perfmon: Spurious overflow interrupt: process %d has "
"no PFM context\n", task->pid);
+ put_cpu();
return;
}
@@ -3104,6 +3139,7 @@
} else {
pfm_stats[smp_processor_id()].pfm_spurious_ovfl_intr_count++;
}
+ put_cpu_no_resched();
}
/* for debug only */
@@ -3174,6 +3210,7 @@
unsigned long dcr;
unsigned long dcr_pp;
+ preempt_disable();
dcr_pp = info & PFM_CPUINFO_DCR_PP ? 1 : 0;
/*
@@ -3184,6 +3221,7 @@
regs = (struct pt_regs *)((unsigned long) task + IA64_STK_OFFSET);
regs--;
ia64_psr(regs)->pp = is_ctxswin ? dcr_pp : 0;
+ preempt_enable();
return;
}
/*
@@ -3199,6 +3237,7 @@
ia64_set_dcr(dcr & ~IA64_DCR_PP);
pfm_clear_psr_pp();
ia64_srlz_i();
+ preempt_enable();
return;
}
/*
@@ -3212,6 +3251,7 @@
pfm_set_psr_pp();
ia64_srlz_i();
}
+ preempt_enable();
}
void
@@ -3222,6 +3262,8 @@
u64 psr;
int i;
+ preempt_disable();
+
ctx = task->thread.pfm_context;
@@ -3275,6 +3317,7 @@
*/
atomic_set(&ctx->ctx_last_cpu, -1);
#endif
+ preempt_enable();
}
static void
@@ -3285,6 +3328,7 @@
unsigned long mask;
int i;
+ preempt_disable();
DBprintk(("on [%d] by [%d]\n", task->pid, current->pid));
t = &task->thread;
@@ -3311,6 +3355,7 @@
/* not owned by this CPU */
atomic_set(&ctx->ctx_last_cpu, -1);
+ preempt_enable();
}
void
@@ -3323,11 +3368,14 @@
u64 psr;
int i;
+ preempt_disable();
+
owner = PMU_OWNER();
ctx = task->thread.pfm_context;
t = &task->thread;
if (ctx == NULL) {
+ preempt_enable();
printk("perfmon: pfm_load_regs: null ctx for [%d]\n", task->pid);
return;
}
@@ -3366,7 +3414,7 @@
psr = ctx->ctx_saved_psr;
pfm_set_psr_l(psr);
-
+ preempt_enable();
return;
}
@@ -3428,6 +3476,7 @@
* restore the psr we changed in pfm_save_regs()
*/
psr = ctx->ctx_saved_psr;
+ preempt_enable();
pfm_set_psr_l(psr);
}
@@ -3445,6 +3494,7 @@
printk("perfmon: invalid task in pfm_reset_pmu()\n");
return;
}
+ preempt_disable();
/* Let's make sure the PMU is frozen */
pfm_freeze_pmu();
@@ -3527,6 +3577,7 @@
ctx->ctx_used_dbrs[0] = 0UL;
ia64_srlz_d();
+ preempt_enable();
}
/*
@@ -3556,6 +3607,7 @@
*/
if (ctx->ctx_flags.state == PFM_CTX_DISABLED) return;
+ preempt_disable();
/*
* stop monitoring:
* This is the only way to stop monitoring without destroying overflow
@@ -3683,7 +3735,7 @@
* indicates that context has been saved
*/
atomic_set(&ctx->ctx_last_cpu, -1);
-
+ preempt_enable();
}
@@ -3706,6 +3758,7 @@
ctx = task->thread.pfm_context;
thread = &task->thread;
+ preempt_disable();
/*
* make sure child cannot mess up the monitoring session
*/
@@ -3760,6 +3813,8 @@
*/
ia64_psr(regs)->up = 0;
+ preempt_enable();
+
/* copy_thread() clears IA64_THREAD_PM_VALID */
return 0;
}
@@ -3865,6 +3920,8 @@
thread->flags |= IA64_THREAD_PM_VALID;
}
+ preempt_enable();
+
return 0;
}
@@ -3886,6 +3943,7 @@
/*
* check sampling buffer
*/
+ preempt_disable();
if (ctx->ctx_psb) {
pfm_smpl_buffer_desc_t *psb = ctx->ctx_psb;
@@ -3978,6 +4036,7 @@
}
UNLOCK_CTX(ctx);
+ preempt_enable();
pfm_unreserve_session(task, ctx->ctx_fl_system, 1UL << ctx->ctx_cpu);
@@ -4156,17 +4215,27 @@
{
int ret;
+
/* some sanity checks */
- if (hdl == NULL || hdl->handler == NULL) return -EINVAL;
+ if (hdl == NULL || hdl->handler == NULL) {
+ return -EINVAL;
+ }
/* do the easy test first */
- if (pfm_alternate_intr_handler) return -EBUSY;
+ if (pfm_alternate_intr_handler) {
+ return -EBUSY;
+ }
+ preempt_disable();
/* reserve our session */
ret = pfm_reserve_session(NULL, 1, cpu_online_map);
- if (ret) return ret;
+ if (ret) {
+ preempt_enable();
+ return ret;
+ }
if (pfm_alternate_intr_handler) {
+ preempt_enable();
printk(KERN_DEBUG "perfmon: install_alternate, intr_handler not NULL "
"after reserve\n");
return -EINVAL;
@@ -4174,17 +4243,21 @@
pfm_alternate_intr_handler = hdl;
+ preempt_enable();
return 0;
}
int
pfm_remove_alternate_syswide_subsystem(pfm_intr_handler_desc_t *hdl)
{
- if (hdl == NULL) return -EINVAL;
+ if (hdl == NULL)
+ return -EINVAL;
/* cannot remove someone else's handler! */
- if (pfm_alternate_intr_handler != hdl) return -EINVAL;
+ if (pfm_alternate_intr_handler != hdl)
+ return -EINVAL;
+ preempt_disable();
pfm_alternate_intr_handler = NULL;
/*
@@ -4192,6 +4265,8 @@
*/
pfm_unreserve_session(NULL, 1, cpu_online_map);
+ preempt_enable();
+
return 0;
}
@@ -4272,8 +4347,9 @@
pfm_init_percpu(void)
{
int i;
+ int me = get_cpu();
- if (smp_processor_id() == 0)
+ if (me == 0)
register_percpu_irq(IA64_PERFMON_VECTOR, &perfmon_irqaction);
ia64_set_pmv(IA64_PERFMON_VECTOR);
@@ -4297,6 +4373,7 @@
if (PMD_IS_IMPL(i) == 0) continue;
ia64_set_pmd(i, 0UL);
}
+ put_cpu();
pfm_freeze_pmu();
}
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/arch/ia64/kernel/smp.c linux-2.5-preempt/arch/ia64/kernel/smp.c
--- linux-2.5-EXPORT/arch/ia64/kernel/smp.c Wed Jan 29 13:55:00 2003
+++ linux-2.5-preempt/arch/ia64/kernel/smp.c Thu Jan 30 14:14:13 2003
@@ -90,7 +90,7 @@
void
handle_IPI (int irq, void *dev_id, struct pt_regs *regs)
{
- int this_cpu = smp_processor_id();
+ int this_cpu = get_cpu();
unsigned long *pending_ipis = &__get_cpu_var(ipi_operation);
unsigned long ops;
@@ -146,8 +146,12 @@
} while (ops);
mb(); /* Order data access and bit testing. */
}
+ put_cpu();
}
+/*
+ * Called with preeemption disabled
+ */
static inline void
send_IPI_single (int dest_cpu, int op)
{
@@ -155,6 +159,9 @@
platform_send_ipi(dest_cpu, IA64_IPI_VECTOR, IA64_IPI_DM_INT, 0);
}
+/*
+ * Called with preeemption disabled
+ */
static inline void
send_IPI_allbutself (int op)
{
@@ -166,6 +173,9 @@
}
}
+/*
+ * Called with preeemption disabled
+ */
static inline void
send_IPI_all (int op)
{
@@ -176,12 +186,18 @@
send_IPI_single(i, op);
}
+/*
+ * Called with preeemption disabled
+ */
static inline void
send_IPI_self (int op)
{
send_IPI_single(smp_processor_id(), op);
}
+/*
+ * Called with preeemption disabled
+ */
void
smp_send_reschedule (int cpu)
{
@@ -197,12 +213,15 @@
smp_send_reschedule_all (void)
{
int i;
+ int cpu = get_cpu(); /* disable preemption */
for (i = 0; i < NR_CPUS; i++)
- if (cpu_online(i) && i != smp_processor_id())
+ if (cpu_online(i) && i != cpu)
smp_send_reschedule(i);
+ put_cpu();
}
+
void
smp_flush_tlb_all (void)
{
@@ -247,9 +266,11 @@
{
struct call_data_struct data;
int cpus = 1;
+ int me = get_cpu(); /* prevent preemption and reschedule on another processor */
- if (cpuid == smp_processor_id()) {
+ if (cpuid == me) {
printk("%s: trying to call self\n", __FUNCTION__);
+ put_cpu();
return -EBUSY;
}
@@ -276,6 +297,7 @@
call_data = NULL;
spin_unlock_bh(&call_lock);
+ put_cpu();
return 0;
}
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/arch/ia64/mm/fault.c linux-2.5-preempt/arch/ia64/mm/fault.c
--- linux-2.5-EXPORT/arch/ia64/mm/fault.c Thu Feb 13 13:26:52 2003
+++ linux-2.5-preempt/arch/ia64/mm/fault.c Thu Feb 13 13:43:47 2003
@@ -55,7 +55,7 @@
/*
* If we're in an interrupt or have no user context, we must not take the fault..
*/
- if (in_interrupt() || !mm)
+ if (in_atomic() || !mm)
goto no_context;
#ifdef CONFIG_VIRTUAL_MEM_MAP
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/arch/ia64/mm/tlb.c linux-2.5-preempt/arch/ia64/mm/tlb.c
--- linux-2.5-EXPORT/arch/ia64/mm/tlb.c Wed Jan 29 13:55:00 2003
+++ linux-2.5-preempt/arch/ia64/mm/tlb.c Thu Jan 30 14:14:13 2003
@@ -81,9 +81,13 @@
}
read_unlock(&tasklist_lock);
/* can't call flush_tlb_all() here because of race condition with O(1) scheduler [EF] */
- for (i = 0; i < NR_CPUS; ++i)
- if (i != smp_processor_id())
- per_cpu(ia64_need_tlb_flush, i) = 1;
+ {
+ int cpu = get_cpu(); /* prevent preemption/migration */
+ for (i = 0; i < NR_CPUS; ++i)
+ if (i != cpu)
+ per_cpu(ia64_need_tlb_flush, i) = 1;
+ put_cpu();
+ }
local_flush_tlb_all();
}
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/include/asm-ia64/hardirq.h linux-2.5-preempt/include/asm-ia64/hardirq.h
--- linux-2.5-EXPORT/include/asm-ia64/hardirq.h Fri Dec 20 11:47:33 2002
+++ linux-2.5-preempt/include/asm-ia64/hardirq.h Wed Feb 5 11:03:22 2003
@@ -32,18 +32,18 @@
*
* - bits 0-7 are the preemption count (max preemption depth: 256)
* - bits 8-15 are the softirq count (max # of softirqs: 256)
- * - bits 16-31 are the hardirq count (max # of hardirqs: 65536)
+ * - bits 16-29 are the hardirq count (max # of hardirqs: 16384)
*
* - (bit 63 is the PREEMPT_ACTIVE flag---not currently implemented.)
*
* PREEMPT_MASK: 0x000000ff
* SOFTIRQ_MASK: 0x0000ff00
- * HARDIRQ_MASK: 0xffff0000
+ * HARDIRQ_MASK: 0x3fff0000
*/
#define PREEMPT_BITS 8
#define SOFTIRQ_BITS 8
-#define HARDIRQ_BITS 16
+#define HARDIRQ_BITS 14
#define PREEMPT_SHIFT 0
#define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS)
@@ -83,13 +83,13 @@
#define hardirq_trylock() (!in_interrupt())
#define hardirq_endlock() do { } while (0)
-#define in_atomic() (preempt_count() != 0)
#define irq_enter() (preempt_count() += HARDIRQ_OFFSET)
#if CONFIG_PREEMPT
-# error CONFIG_PREEMT currently not supported.
+# define in_atomic() ((preempt_count() & ~PREEMPT_ACTIVE) != kernel_locked())
# define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
#else
+# define in_atomic() (preempt_count() != 0)
# define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
#endif
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/include/asm-ia64/spinlock.h linux-2.5-preempt/include/asm-ia64/spinlock.h
--- linux-2.5-EXPORT/include/asm-ia64/spinlock.h Wed Jan 29 13:55:21 2003
+++ linux-2.5-preempt/include/asm-ia64/spinlock.h Wed Feb 5 09:35:40 2003
@@ -189,4 +189,19 @@
clear_bit(31, (x)); \
})
+#define _raw_write_trylock(rw) \
+({ \
+ register long result; \
+ \
+ __asm__ __volatile__ ( \
+ "mov ar.ccv = r0\n" \
+ "dep r29 = -1, r0, 31, 1\n" \
+ ";;\n" \
+ "1:\n" \
+ "cmpxchg4.acq %0 = [%1], r29, ar.ccv\n" \
+ :"=r"(result) :"r"(rw) : "ar.ccv", "r2", "r29", "memory"); \
+ (result == 0); \
+})
+
+
#endif /* _ASM_IA64_SPINLOCK_H */
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/include/asm-ia64/system.h linux-2.5-preempt/include/asm-ia64/system.h
--- linux-2.5-EXPORT/include/asm-ia64/system.h Wed Jan 29 13:55:21 2003
+++ linux-2.5-preempt/include/asm-ia64/system.h Thu Jan 30 14:15:28 2003
@@ -206,7 +206,7 @@
#ifdef CONFIG_PERFMON
DECLARE_PER_CPU(unsigned long, pfm_syst_info);
-# define PERFMON_IS_SYSWIDE() (get_cpu_var(pfm_syst_info) & 0x1)
+# define PERFMON_IS_SYSWIDE() (__get_cpu_var(pfm_syst_info) & 0x1)
#else
# define PERFMON_IS_SYSWIDE() (0)
#endif
diff -Nur --exclude=RCS --exclude=CVS --exclude=SCCS --exclude=BitKeeper --exclude=ChangeSet linux-2.5-EXPORT/include/asm-ia64/thread_info.h linux-2.5-preempt/include/asm-ia64/thread_info.h
--- linux-2.5-EXPORT/include/asm-ia64/thread_info.h Wed Jan 29 13:55:21 2003
+++ linux-2.5-preempt/include/asm-ia64/thread_info.h Wed Feb 5 11:03:22 2003
@@ -15,7 +15,8 @@
#define TI_ADDR_LIMIT 0x10
#define TI_PRE_COUNT 0x18
-#define PREEMPT_ACTIVE 0x4000000
+#define PREEMPT_ACTIVE_BIT 30
+#define PREEMPT_ACTIVE (1<<PREEMPT_ACTIVE_BIT)
#ifndef __ASSEMBLY__
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2003-02-14 4:16 UTC | newest]
Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2003-02-14 4:16 [Linux-ia64] Preemption patch against ~2.5.60 Peter Chubb
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox