LXR linux/drivers/gpu/drm/i915/i915

   1// SPDX-License-Identifier: MIT
   2/*
   3 * Copyright © 2019 Intel Corporation
   4 */
   5
   6#include <drm/drm_drv.h>
   7
   8#include "i915_drv.h"
   9#include "i915_utils.h"
  10
  11#define FDO_BUG_MSG "Please file a bug on drm/i915; see " FDO_BUG_URL " for details."
  12
  13void
  14__i915_printk(struct drm_i915_private *dev_priv, const char *level,
  15              const char *fmt, ...)
  16{
  17        static bool shown_bug_once;
  18        struct device *kdev = dev_priv->drm.dev;
  19        bool is_error = level[1] <= KERN_ERR[1];
  20        bool is_debug = level[1] == KERN_DEBUG[1];
  21        struct va_format vaf;
  22        va_list args;
  23
  24        if (is_debug && !drm_debug_enabled(DRM_UT_DRIVER))
  25                return;
  26
  27        va_start(args, fmt);
  28
  29        vaf.fmt = fmt;
  30        vaf.va = &args;
  31
  32        if (is_error)
  33                dev_printk(level, kdev, "%pV", &vaf);
  34        else
  35                dev_printk(level, kdev, "[" DRM_NAME ":%ps] %pV",
  36                           __builtin_return_address(0), &vaf);
  37
  38        va_end(args);
  39
  40        if (is_error && !shown_bug_once) {
  41                /*
  42                 * Ask the user to file a bug report for the error, except
  43                 * if they may have caused the bug by fiddling with unsafe
  44                 * module parameters.
  45                 */
  46                if (!test_taint(TAINT_USER))
  47                        dev_notice(kdev, "%s", FDO_BUG_MSG);
  48                shown_bug_once = true;
  49        }
  50}
  51
  52void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint)
  53{
  54        __i915_printk(i915, KERN_NOTICE, "CI tainted:%#x by %pS\n",
  55                      taint, (void *)_RET_IP_);
  56
  57        /* Failures that occur during fault injection testing are expected */
  58        if (!i915_error_injected())
  59                __add_taint_for_CI(taint);
  60}
  61
  62#if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
  63static unsigned int i915_probe_fail_count;
  64
  65int __i915_inject_probe_error(struct drm_i915_private *i915, int err,
  66                              const char *func, int line)
  67{
  68        if (i915_probe_fail_count >= i915_modparams.inject_probe_failure)
  69                return 0;
  70
  71        if (++i915_probe_fail_count < i915_modparams.inject_probe_failure)
  72                return 0;
  73
  74        __i915_printk(i915, KERN_INFO,
  75                      "Injecting failure %d at checkpoint %u [%s:%d]\n",
  76                      err, i915_modparams.inject_probe_failure, func, line);
  77        i915_modparams.inject_probe_failure = 0;
  78        return err;
  79}
  80
  81bool i915_error_injected(void)
  82{
  83        return i915_probe_fail_count && !i915_modparams.inject_probe_failure;
  84}
  85
  86#endif
  87
  88void cancel_timer(struct timer_list *t)
  89{
  90        if (!timer_active(t))
  91                return;
  92
  93        del_timer(t);
  94        WRITE_ONCE(t->expires, 0);
  95}
  96
  97void set_timer_ms(struct timer_list *t, unsigned long timeout)
  98{
  99        if (!timeout) {
 100                cancel_timer(t);
 101                return;
 102        }
 103
 104        timeout = msecs_to_jiffies(timeout);
 105
 106        /*
 107         * Paranoia to make sure the compiler computes the timeout before
 108         * loading 'jiffies' as jiffies is volatile and may be updated in
 109         * the background by a timer tick. All to reduce the complexity
 110         * of the addition and reduce the risk of losing a jiffie.
 111         */
 112        barrier();
 113
 114        /* Keep t->expires = 0 reserved to indicate a canceled timer. */
 115        mod_timer(t, jiffies + timeout ?: 1);
 116}
 117