[PATCH v5 3/4] PCI/VGA: Tidy up the code and comment format
Sui Jingfeng
suijingfeng at loongson.cn
Fri Jun 9 12:30:50 UTC 2023
Hi,
On 2023/6/9 20:00, Andi Shyti wrote:
> Hi Sui,
>
> On Fri, Jun 09, 2023 at 07:24:16PM +0800, Sui Jingfeng wrote:
>> This patch replaces the leading space with a tab and removes the double
>> blank line, no functional change.
> You mainly fixed comment style, though and it's not written here.
>
> No need to resend for me as you also wrote it in the title. But
> next time please list all the changes in the commit log.
OK, I remember this.
This patch is trivial, that's fine.
There are probably more complex patch in future, probably will send to
you if the checkpatch.pl script mandate it.
:-)
Thanks a lot really.
>> Signed-off-by: Sui Jingfeng <suijingfeng at loongson.cn>
> Reviewed-by: Andi Shyti <andi.shyti at linux.intel.com>
>
> Andi
>
>> ---
>> drivers/pci/vgaarb.c | 108 ++++++++++++++++++++++++-----------------
>> include/linux/vgaarb.h | 4 +-
>> 2 files changed, 65 insertions(+), 47 deletions(-)
>>
>> diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c
>> index 22a505e877dc..ceb914245383 100644
>> --- a/drivers/pci/vgaarb.c
>> +++ b/drivers/pci/vgaarb.c
>> @@ -61,7 +61,6 @@ static bool vga_arbiter_used;
>> static DEFINE_SPINLOCK(vga_lock);
>> static DECLARE_WAIT_QUEUE_HEAD(vga_wait_queue);
>>
>> -
>> static const char *vga_iostate_to_str(unsigned int iostate)
>> {
>> /* Ignore VGA_RSRC_IO and VGA_RSRC_MEM */
>> @@ -79,8 +78,10 @@ static const char *vga_iostate_to_str(unsigned int iostate)
>>
>> static int vga_str_to_iostate(char *buf, int str_size, unsigned int *io_state)
>> {
>> - /* we could in theory hand out locks on IO and mem
>> - * separately to userspace but it can cause deadlocks */
>> + /*
>> + * We could in theory hand out locks on IO and mem
>> + * separately to userspace but it can cause deadlocks
>> + */
>> if (strncmp(buf, "none", 4) == 0) {
>> *io_state = VGA_RSRC_NONE;
>> return 1;
>> @@ -99,7 +100,7 @@ static int vga_str_to_iostate(char *buf, int str_size, unsigned int *io_state)
>> return 1;
>> }
>>
>> -/* this is only used a cookie - it should not be dereferenced */
>> +/* This is only used as cookie, it should not be dereferenced */
>> static struct pci_dev *vga_default;
>>
>> /* Find somebody in our list */
>> @@ -193,14 +194,17 @@ int vga_remove_vgacon(struct pci_dev *pdev)
>> #endif
>> EXPORT_SYMBOL(vga_remove_vgacon);
>>
>> -/* If we don't ever use VGA arb we should avoid
>> - turning off anything anywhere due to old X servers getting
>> - confused about the boot device not being VGA */
>> +/*
>> + * If we don't ever use VGA arb we should avoid
>> + * turning off anything anywhere due to old X servers getting
>> + * confused about the boot device not being VGA
>> + */
>> static void vga_check_first_use(void)
>> {
>> - /* we should inform all GPUs in the system that
>> - * VGA arb has occurred and to try and disable resources
>> - * if they can */
>> + /*
>> + * We should inform all GPUs in the system that
>> + * vgaarb has occurred and to try and disable resources if they can
>> + */
>> if (!vga_arbiter_used) {
>> vga_arbiter_used = true;
>> vga_arbiter_notify_clients();
>> @@ -216,7 +220,8 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
>> unsigned int pci_bits;
>> u32 flags = 0;
>>
>> - /* Account for "normal" resources to lock. If we decode the legacy,
>> + /*
>> + * Account for "normal" resources to lock. If we decode the legacy,
>> * counterpart, we need to request it as well
>> */
>> if ((rsrc & VGA_RSRC_NORMAL_IO) &&
>> @@ -236,7 +241,8 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
>> if (wants == 0)
>> goto lock_them;
>>
>> - /* We don't need to request a legacy resource, we just enable
>> + /*
>> + * We don't need to request a legacy resource, we just enable
>> * appropriate decoding and go
>> */
>> legacy_wants = wants & VGA_RSRC_LEGACY_MASK;
>> @@ -252,7 +258,8 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
>> if (vgadev == conflict)
>> continue;
>>
>> - /* We have a possible conflict. before we go further, we must
>> + /*
>> + * We have a possible conflict. before we go further, we must
>> * check if we sit on the same bus as the conflicting device.
>> * if we don't, then we must tie both IO and MEM resources
>> * together since there is only a single bit controlling
>> @@ -263,13 +270,15 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
>> lwants = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM;
>> }
>>
>> - /* Check if the guy has a lock on the resource. If he does,
>> + /*
>> + * Check if the guy has a lock on the resource. If he does,
>> * return the conflicting entry
>> */
>> if (conflict->locks & lwants)
>> return conflict;
>>
>> - /* Ok, now check if it owns the resource we want. We can
>> + /*
>> + * Ok, now check if it owns the resource we want. We can
>> * lock resources that are not decoded, therefore a device
>> * can own resources it doesn't decode.
>> */
>> @@ -277,14 +286,16 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
>> if (!match)
>> continue;
>>
>> - /* looks like he doesn't have a lock, we can steal
>> + /*
>> + * Looks like he doesn't have a lock, we can steal
>> * them from him
>> */
>>
>> flags = 0;
>> pci_bits = 0;
>>
>> - /* If we can't control legacy resources via the bridge, we
>> + /*
>> + * If we can't control legacy resources via the bridge, we
>> * also need to disable normal decoding.
>> */
>> if (!conflict->bridge_has_one_vga) {
>> @@ -311,7 +322,8 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
>> }
>>
>> enable_them:
>> - /* ok dude, we got it, everybody conflicting has been disabled, let's
>> + /*
>> + * Ok dude, we got it, everybody conflicting has been disabled, let's
>> * enable us. Mark any bits in "owns" regardless of whether we
>> * decoded them. We can lock resources we don't decode, therefore
>> * we must track them via "owns".
>> @@ -353,7 +365,8 @@ static void __vga_put(struct vga_device *vgadev, unsigned int rsrc)
>>
>> vgaarb_dbg(dev, "%s\n", __func__);
>>
>> - /* Update our counters, and account for equivalent legacy resources
>> + /*
>> + * Update our counters, and account for equivalent legacy resources
>> * if we decode them
>> */
>> if ((rsrc & VGA_RSRC_NORMAL_IO) && vgadev->io_norm_cnt > 0) {
>> @@ -371,7 +384,8 @@ static void __vga_put(struct vga_device *vgadev, unsigned int rsrc)
>> if ((rsrc & VGA_RSRC_LEGACY_MEM) && vgadev->mem_lock_cnt > 0)
>> vgadev->mem_lock_cnt--;
>>
>> - /* Just clear lock bits, we do lazy operations so we don't really
>> + /*
>> + * Just clear lock bits, we do lazy operations so we don't really
>> * have to bother about anything else at this point
>> */
>> if (vgadev->io_lock_cnt == 0)
>> @@ -379,7 +393,8 @@ static void __vga_put(struct vga_device *vgadev, unsigned int rsrc)
>> if (vgadev->mem_lock_cnt == 0)
>> vgadev->locks &= ~VGA_RSRC_LEGACY_MEM;
>>
>> - /* Kick the wait queue in case somebody was waiting if we actually
>> + /*
>> + * Kick the wait queue in case somebody was waiting if we actually
>> * released something
>> */
>> if (old_locks != vgadev->locks)
>> @@ -447,8 +462,8 @@ int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible)
>> if (conflict == NULL)
>> break;
>>
>> -
>> - /* We have a conflict, we wait until somebody kicks the
>> + /*
>> + * We have a conflict, we wait until somebody kicks the
>> * work queue. Currently we have one work queue that we
>> * kick each time some resources are released, but it would
>> * be fairly easy to have a per device one so that we only
>> @@ -665,7 +680,7 @@ static bool vga_is_boot_device(struct vga_device *vgadev)
>> }
>>
>> /*
>> - * vgadev has neither IO nor MEM enabled. If we haven't found any
>> + * Vgadev has neither IO nor MEM enabled. If we haven't found any
>> * other VGA devices, it is the best candidate so far.
>> */
>> if (!boot_vga)
>> @@ -706,7 +721,7 @@ static void vga_arbiter_check_bridge_sharing(struct vga_device *vgadev)
>> bus = same_bridge_vgadev->pdev->bus;
>> bridge = bus->self;
>>
>> - /* see if the share a bridge with this device */
>> + /* See if the share a bridge with this device */
>> if (new_bridge == bridge) {
>> /*
>> * If their direct parent bridge is the same
>> @@ -777,9 +792,10 @@ static bool vga_arbiter_add_pci_device(struct pci_dev *pdev)
>> vgadev->decodes = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM |
>> VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
>>
>> - /* by default mark it as decoding */
>> + /* By default, mark it as decoding */
>> vga_decode_count++;
>> - /* Mark that we "own" resources based on our enables, we will
>> + /*
>> + * Mark that we "own" resources based on our enables, we will
>> * clear that below if the bridge isn't forwarding
>> */
>> pci_read_config_word(pdev, PCI_COMMAND, &cmd);
>> @@ -860,7 +876,7 @@ static bool vga_arbiter_del_pci_device(struct pci_dev *pdev)
>> return ret;
>> }
>>
>> -/* this is called with the lock */
>> +/* This is called with the lock */
>> static inline void vga_update_device_decodes(struct vga_device *vgadev,
>> int new_decodes)
>> {
>> @@ -877,7 +893,7 @@ static inline void vga_update_device_decodes(struct vga_device *vgadev,
>> vga_iostate_to_str(vgadev->decodes),
>> vga_iostate_to_str(vgadev->owns));
>>
>> - /* if we removed locked decodes, lock count goes to zero, and release */
>> + /* If we removed locked decodes, lock count goes to zero, and release */
>> if (decodes_unlocked) {
>> if (decodes_unlocked & VGA_RSRC_LEGACY_IO)
>> vgadev->io_lock_cnt = 0;
>> @@ -886,7 +902,7 @@ static inline void vga_update_device_decodes(struct vga_device *vgadev,
>> __vga_put(vgadev, decodes_unlocked);
>> }
>>
>> - /* change decodes counter */
>> + /* Change decodes counter */
>> if (old_decodes & VGA_RSRC_LEGACY_MASK &&
>> !(new_decodes & VGA_RSRC_LEGACY_MASK))
>> vga_decode_count--;
>> @@ -910,14 +926,15 @@ static void __vga_set_legacy_decoding(struct pci_dev *pdev,
>> if (vgadev == NULL)
>> goto bail;
>>
>> - /* don't let userspace futz with kernel driver decodes */
>> + /* Don't let userspace futz with kernel driver decodes */
>> if (userspace && vgadev->set_decode)
>> goto bail;
>>
>> - /* update the device decodes + counter */
>> + /* Update the device decodes + counter */
>> vga_update_device_decodes(vgadev, decodes);
>>
>> - /* XXX if somebody is going from "doesn't decode" to "decodes" state
>> + /*
>> + * XXX if somebody is going from "doesn't decode" to "decodes" state
>> * here, additional care must be taken as we may have pending owner
>> * ship of non-legacy region ...
>> */
>> @@ -952,9 +969,9 @@ EXPORT_SYMBOL(vga_set_legacy_decoding);
>> * @set_decode callback: If a client can disable its GPU VGA resource, it
>> * will get a callback from this to set the encode/decode state.
>> *
>> - * Rationale: we cannot disable VGA decode resources unconditionally some single
>> - * GPU laptops seem to require ACPI or BIOS access to the VGA registers to
>> - * control things like backlights etc. Hopefully newer multi-GPU laptops do
>> + * Rationale: we cannot disable VGA decode resources unconditionally, some
>> + * single GPU laptops seem to require ACPI or BIOS access to the VGA registers
>> + * to control things like backlights etc. Hopefully newer multi-GPU laptops do
>> * something saner, and desktops won't have any special ACPI for this. The
>> * driver will get a callback when VGA arbitration is first used by userspace
>> * since some older X servers have issues.
>> @@ -984,7 +1001,6 @@ int vga_client_register(struct pci_dev *pdev,
>> bail:
>> spin_unlock_irqrestore(&vga_lock, flags);
>> return ret;
>> -
>> }
>> EXPORT_SYMBOL(vga_client_register);
>>
>> @@ -1075,7 +1091,6 @@ static int vga_pci_str_to_vars(char *buf, int count, unsigned int *domain,
>> int n;
>> unsigned int slot, func;
>>
>> -
>> n = sscanf(buf, "PCI:%x:%x:%x.%x", domain, bus, &slot, &func);
>> if (n != 4)
>> return 0;
>> @@ -1310,7 +1325,7 @@ static ssize_t vga_arb_write(struct file *file, const char __user *buf,
>> curr_pos += 7;
>> remaining -= 7;
>> pr_debug("client 0x%p called 'target'\n", priv);
>> - /* if target is default */
>> + /* If target is default */
>> if (!strncmp(curr_pos, "default", 7))
>> pdev = pci_dev_get(vga_default_device());
>> else {
>> @@ -1427,7 +1442,6 @@ static int vga_arb_open(struct inode *inode, struct file *file)
>> priv->cards[0].io_cnt = 0;
>> priv->cards[0].mem_cnt = 0;
>>
>> -
>> return 0;
>> }
>>
>> @@ -1461,7 +1475,7 @@ static int vga_arb_release(struct inode *inode, struct file *file)
>> }
>>
>> /*
>> - * callback any registered clients to let them know we have a
>> + * Callback any registered clients to let them know we have a
>> * change in VGA cards
>> */
>> static void vga_arbiter_notify_clients(void)
>> @@ -1500,9 +1514,11 @@ static int pci_notify(struct notifier_block *nb, unsigned long action,
>> if (pdev->class != PCI_CLASS_DISPLAY_VGA << 8)
>> return 0;
>>
>> - /* For now we're only intereted in devices added and removed. I didn't
>> + /*
>> + * For now we're only intereted in devices added and removed. I didn't
>> * test this thing here, so someone needs to double check for the
>> - * cases of hotplugable vga cards. */
>> + * cases of hotplugable vga cards.
>> + */
>> if (action == BUS_NOTIFY_ADD_DEVICE)
>> notify = vga_arbiter_add_pci_device(pdev);
>> else if (action == BUS_NOTIFY_DEL_DEVICE)
>> @@ -1543,8 +1559,10 @@ static int __init vga_arb_device_init(void)
>>
>> bus_register_notifier(&pci_bus_type, &pci_notifier);
>>
>> - /* We add all PCI devices satisfying VGA class in the arbiter by
>> - * default */
>> + /*
>> + * We add all PCI devices satisfying VGA class in the arbiter by
>> + * default
>> + */
>> while (1) {
>> pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev);
>> if (!pdev)
>> diff --git a/include/linux/vgaarb.h b/include/linux/vgaarb.h
>> index b4b9137f9792..6d5465f8c3f2 100644
>> --- a/include/linux/vgaarb.h
>> +++ b/include/linux/vgaarb.h
>> @@ -96,7 +96,7 @@ static inline int vga_client_register(struct pci_dev *pdev,
>> static inline int vga_get_interruptible(struct pci_dev *pdev,
>> unsigned int rsrc)
>> {
>> - return vga_get(pdev, rsrc, 1);
>> + return vga_get(pdev, rsrc, 1);
>> }
>>
>> /**
>> @@ -111,7 +111,7 @@ static inline int vga_get_interruptible(struct pci_dev *pdev,
>> static inline int vga_get_uninterruptible(struct pci_dev *pdev,
>> unsigned int rsrc)
>> {
>> - return vga_get(pdev, rsrc, 0);
>> + return vga_get(pdev, rsrc, 0);
>> }
>>
>> static inline void vga_client_unregister(struct pci_dev *pdev)
>> --
>> 2.25.1
--
Jingfeng
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