summaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/ds.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/ds.c')
-rw-r--r--arch/x86/kernel/ds.c97
1 files changed, 52 insertions, 45 deletions
diff --git a/arch/x86/kernel/ds.c b/arch/x86/kernel/ds.c
index d1a121443bd..d6938d9351c 100644
--- a/arch/x86/kernel/ds.c
+++ b/arch/x86/kernel/ds.c
@@ -21,8 +21,6 @@
*/
-#ifdef CONFIG_X86_DS
-
#include <asm/ds.h>
#include <linux/errno.h>
@@ -211,14 +209,15 @@ static DEFINE_PER_CPU(struct ds_context *, system_context);
static inline struct ds_context *ds_get_context(struct task_struct *task)
{
struct ds_context *context;
+ unsigned long irq;
- spin_lock(&ds_lock);
+ spin_lock_irqsave(&ds_lock, irq);
context = (task ? task->thread.ds_ctx : this_system_context);
if (context)
context->count++;
- spin_unlock(&ds_lock);
+ spin_unlock_irqrestore(&ds_lock, irq);
return context;
}
@@ -226,55 +225,46 @@ static inline struct ds_context *ds_get_context(struct task_struct *task)
/*
* Same as ds_get_context, but allocates the context and it's DS
* structure, if necessary; returns NULL; if out of memory.
- *
- * pre: requires ds_lock to be held
*/
static inline struct ds_context *ds_alloc_context(struct task_struct *task)
{
struct ds_context **p_context =
(task ? &task->thread.ds_ctx : &this_system_context);
struct ds_context *context = *p_context;
+ unsigned long irq;
if (!context) {
- spin_unlock(&ds_lock);
-
context = kzalloc(sizeof(*context), GFP_KERNEL);
-
- if (!context) {
- spin_lock(&ds_lock);
+ if (!context)
return NULL;
- }
context->ds = kzalloc(ds_cfg.sizeof_ds, GFP_KERNEL);
if (!context->ds) {
kfree(context);
- spin_lock(&ds_lock);
return NULL;
}
- spin_lock(&ds_lock);
- /*
- * Check for race - another CPU could have allocated
- * it meanwhile:
- */
+ spin_lock_irqsave(&ds_lock, irq);
+
if (*p_context) {
kfree(context->ds);
kfree(context);
- return *p_context;
- }
- *p_context = context;
+ context = *p_context;
+ } else {
+ *p_context = context;
- context->this = p_context;
- context->task = task;
+ context->this = p_context;
+ context->task = task;
- if (task)
- set_tsk_thread_flag(task, TIF_DS_AREA_MSR);
+ if (task)
+ set_tsk_thread_flag(task, TIF_DS_AREA_MSR);
- if (!task || (task == current))
- wrmsr(MSR_IA32_DS_AREA, (unsigned long)context->ds, 0);
-
- get_tracer(task);
+ if (!task || (task == current))
+ wrmsrl(MSR_IA32_DS_AREA,
+ (unsigned long)context->ds);
+ }
+ spin_unlock_irqrestore(&ds_lock, irq);
}
context->count++;
@@ -288,10 +278,12 @@ static inline struct ds_context *ds_alloc_context(struct task_struct *task)
*/
static inline void ds_put_context(struct ds_context *context)
{
+ unsigned long irq;
+
if (!context)
return;
- spin_lock(&ds_lock);
+ spin_lock_irqsave(&ds_lock, irq);
if (--context->count)
goto out;
@@ -313,7 +305,7 @@ static inline void ds_put_context(struct ds_context *context)
kfree(context->ds);
kfree(context);
out:
- spin_unlock(&ds_lock);
+ spin_unlock_irqrestore(&ds_lock, irq);
}
@@ -384,6 +376,7 @@ static int ds_request(struct task_struct *task, void *base, size_t size,
struct ds_context *context;
unsigned long buffer, adj;
const unsigned long alignment = (1 << 3);
+ unsigned long irq;
int error = 0;
if (!ds_cfg.sizeof_ds)
@@ -398,26 +391,27 @@ static int ds_request(struct task_struct *task, void *base, size_t size,
return -EOPNOTSUPP;
- spin_lock(&ds_lock);
-
- error = -ENOMEM;
context = ds_alloc_context(task);
if (!context)
- goto out_unlock;
+ return -ENOMEM;
+
+ spin_lock_irqsave(&ds_lock, irq);
error = -EPERM;
if (!check_tracer(task))
goto out_unlock;
+ get_tracer(task);
+
error = -EALREADY;
if (context->owner[qual] == current)
- goto out_unlock;
+ goto out_put_tracer;
error = -EPERM;
if (context->owner[qual] != NULL)
- goto out_unlock;
+ goto out_put_tracer;
context->owner[qual] = current;
- spin_unlock(&ds_lock);
+ spin_unlock_irqrestore(&ds_lock, irq);
error = -ENOMEM;
@@ -465,10 +459,17 @@ static int ds_request(struct task_struct *task, void *base, size_t size,
out_release:
context->owner[qual] = NULL;
ds_put_context(context);
+ put_tracer(task);
+ return error;
+
+ out_put_tracer:
+ spin_unlock_irqrestore(&ds_lock, irq);
+ ds_put_context(context);
+ put_tracer(task);
return error;
out_unlock:
- spin_unlock(&ds_lock);
+ spin_unlock_irqrestore(&ds_lock, irq);
ds_put_context(context);
return error;
}
@@ -818,13 +819,21 @@ static const struct ds_configuration ds_cfg_var = {
.sizeof_ds = sizeof(long) * 12,
.sizeof_field = sizeof(long),
.sizeof_rec[ds_bts] = sizeof(long) * 3,
+#ifdef __i386__
.sizeof_rec[ds_pebs] = sizeof(long) * 10
+#else
+ .sizeof_rec[ds_pebs] = sizeof(long) * 18
+#endif
};
static const struct ds_configuration ds_cfg_64 = {
.sizeof_ds = 8 * 12,
.sizeof_field = 8,
.sizeof_rec[ds_bts] = 8 * 3,
+#ifdef __i386__
.sizeof_rec[ds_pebs] = 8 * 10
+#else
+ .sizeof_rec[ds_pebs] = 8 * 18
+#endif
};
static inline void
@@ -838,17 +847,16 @@ void __cpuinit ds_init_intel(struct cpuinfo_x86 *c)
switch (c->x86) {
case 0x6:
switch (c->x86_model) {
+ case 0 ... 0xC:
+ /* sorry, don't know about them */
+ break;
case 0xD:
case 0xE: /* Pentium M */
ds_configure(&ds_cfg_var);
break;
- case 0xF: /* Core2 */
- case 0x1C: /* Atom */
+ default: /* Core2, Atom, ... */
ds_configure(&ds_cfg_64);
break;
- default:
- /* sorry, don't know about them */
- break;
}
break;
case 0xF:
@@ -878,4 +886,3 @@ void ds_free(struct ds_context *context)
while (leftovers--)
ds_put_context(context);
}
-#endif /* CONFIG_X86_DS */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-24 19:04:55 +0000