linux_dsm_epyc7002/drivers/gpu/drm/i915/i915_utils.c
Chris Wilson bfae03fe75 drm/i915: Avoid setting timer->expires to 0
We use timer->expires == 0 to detect if a timer had been cancelled, but
it's a valid expiration we could set. Just skip using 0 and set the
expiry for the next jiffie.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200403073657.13427-1-chris@chris-wilson.co.uk
2020-04-03 16:33:09 +01:00

107 lines
2.4 KiB
C

// SPDX-License-Identifier: MIT
/*
* Copyright © 2019 Intel Corporation
*/
#include <drm/drm_drv.h>
#include "i915_drv.h"
#include "i915_utils.h"
#define FDO_BUG_MSG "Please file a bug on drm/i915; see " FDO_BUG_URL " for details."
void
__i915_printk(struct drm_i915_private *dev_priv, const char *level,
const char *fmt, ...)
{
static bool shown_bug_once;
struct device *kdev = dev_priv->drm.dev;
bool is_error = level[1] <= KERN_ERR[1];
bool is_debug = level[1] == KERN_DEBUG[1];
struct va_format vaf;
va_list args;
if (is_debug && !drm_debug_enabled(DRM_UT_DRIVER))
return;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
if (is_error)
dev_printk(level, kdev, "%pV", &vaf);
else
dev_printk(level, kdev, "[" DRM_NAME ":%ps] %pV",
__builtin_return_address(0), &vaf);
va_end(args);
if (is_error && !shown_bug_once) {
/*
* Ask the user to file a bug report for the error, except
* if they may have caused the bug by fiddling with unsafe
* module parameters.
*/
if (!test_taint(TAINT_USER))
dev_notice(kdev, "%s", FDO_BUG_MSG);
shown_bug_once = true;
}
}
#if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
static unsigned int i915_probe_fail_count;
int __i915_inject_probe_error(struct drm_i915_private *i915, int err,
const char *func, int line)
{
if (i915_probe_fail_count >= i915_modparams.inject_probe_failure)
return 0;
if (++i915_probe_fail_count < i915_modparams.inject_probe_failure)
return 0;
__i915_printk(i915, KERN_INFO,
"Injecting failure %d at checkpoint %u [%s:%d]\n",
err, i915_modparams.inject_probe_failure, func, line);
i915_modparams.inject_probe_failure = 0;
return err;
}
bool i915_error_injected(void)
{
return i915_probe_fail_count && !i915_modparams.inject_probe_failure;
}
#endif
void cancel_timer(struct timer_list *t)
{
if (!READ_ONCE(t->expires))
return;
del_timer(t);
WRITE_ONCE(t->expires, 0);
}
void set_timer_ms(struct timer_list *t, unsigned long timeout)
{
if (!timeout) {
cancel_timer(t);
return;
}
timeout = msecs_to_jiffies_timeout(timeout);
/*
* Paranoia to make sure the compiler computes the timeout before
* loading 'jiffies' as jiffies is volatile and may be updated in
* the background by a timer tick. All to reduce the complexity
* of the addition and reduce the risk of losing a jiffie.
*/
barrier();
/* Keep t->expires = 0 reserved to indicate a canceled timer. */
mod_timer(t, jiffies + timeout ?: 1);
}