1. Patchew
  2. linux
  3. [PATCH v4 0/2] Converge on using secs_to_jiffies() part two
  4. View patch

[PATCH v4 1/2] rbd: convert timeouts to secs_to_jiffies()

Easwar Hariharan posted 2 patches 11 months, 1 week ago
[PATCH v4 1/2] rbd: convert timeouts to secs_to_jiffies()
Posted by Easwar Hariharan 11 months, 1 week ago 
Commit b35108a51cf7 ("jiffies: Define secs_to_jiffies()") introduced
secs_to_jiffies().  As the value here is a multiple of 1000, use
secs_to_jiffies() instead of msecs_to_jiffies() to avoid the multiplication

This is converted using scripts/coccinelle/misc/secs_to_jiffies.cocci with
the following Coccinelle rules:

@depends on patch@ expression E; @@

-msecs_to_jiffies(E * 1000)
+secs_to_jiffies(E)

@depends on patch@ expression E; @@

-msecs_to_jiffies(E * MSEC_PER_SEC)
+secs_to_jiffies(E)

Change the check for range to check against HZ.

Acked-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com>
---
 drivers/block/rbd.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index faafd7ff43d6ef53110ab3663cc7ac322214cc8c..1c406b17f3cee741b7bdd9f742958b3f1d5b1bbe 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -108,7 +108,7 @@ static int atomic_dec_return_safe(atomic_t *v)
 #define RBD_OBJ_PREFIX_LEN_MAX	64
 
 #define RBD_NOTIFY_TIMEOUT	5	/* seconds */
-#define RBD_RETRY_DELAY		msecs_to_jiffies(1000)
+#define RBD_RETRY_DELAY		secs_to_jiffies(1)
 
 /* Feature bits */
 
@@ -4162,7 +4162,7 @@ static void rbd_acquire_lock(struct work_struct *work)
 		dout("%s rbd_dev %p requeuing lock_dwork\n", __func__,
 		     rbd_dev);
 		mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
-		    msecs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT * MSEC_PER_SEC));
+		    secs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT));
 	}
 }
 
@@ -6283,9 +6283,9 @@ static int rbd_parse_param(struct fs_parameter *param,
 		break;
 	case Opt_lock_timeout:
 		/* 0 is "wait forever" (i.e. infinite timeout) */
-		if (result.uint_32 > INT_MAX / 1000)
+		if (result.uint32 > INT_MAX / HZ)
 			goto out_of_range;
-		opt->lock_timeout = msecs_to_jiffies(result.uint_32 * 1000);
+		opt->lock_timeout = secs_to_jiffies(result.uint_32);
 		break;
 	case Opt_pool_ns:
 		kfree(pctx->spec->pool_ns);

-- 
2.43.0
Re: [PATCH v4 1/2] rbd: convert timeouts to secs_to_jiffies()
Posted by Alex Elder 11 months, 1 week ago 
On 2/28/25 10:22 PM, Easwar Hariharan wrote:
> Commit b35108a51cf7 ("jiffies: Define secs_to_jiffies()") introduced
> secs_to_jiffies().  As the value here is a multiple of 1000, use
> secs_to_jiffies() instead of msecs_to_jiffies() to avoid the multiplication
> 
> This is converted using scripts/coccinelle/misc/secs_to_jiffies.cocci with
> the following Coccinelle rules:
> 
> @depends on patch@ expression E; @@
> 
> -msecs_to_jiffies(E * 1000)
> +secs_to_jiffies(E)
> 
> @depends on patch@ expression E; @@
> 
> -msecs_to_jiffies(E * MSEC_PER_SEC)
> +secs_to_jiffies(E)
> 
> Change the check for range to check against HZ.
> 
> Acked-by: Ilya Dryomov <idryomov@gmail.com>
> Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com>

I think what you've done in the last hunk below should not be
done that way.  I also suggest something to the (related, but
not part of this series) secs_to_jiffies() implementation.

> ---
>   drivers/block/rbd.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
> index faafd7ff43d6ef53110ab3663cc7ac322214cc8c..1c406b17f3cee741b7bdd9f742958b3f1d5b1bbe 100644
> --- a/drivers/block/rbd.c
> +++ b/drivers/block/rbd.c
> @@ -108,7 +108,7 @@ static int atomic_dec_return_safe(atomic_t *v)
>   #define RBD_OBJ_PREFIX_LEN_MAX	64
>   
>   #define RBD_NOTIFY_TIMEOUT	5	/* seconds */
> -#define RBD_RETRY_DELAY		msecs_to_jiffies(1000)
> +#define RBD_RETRY_DELAY		secs_to_jiffies(1)
>   
>   /* Feature bits */
>   
> @@ -4162,7 +4162,7 @@ static void rbd_acquire_lock(struct work_struct *work)
>   		dout("%s rbd_dev %p requeuing lock_dwork\n", __func__,
>   		     rbd_dev);
>   		mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
> -		    msecs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT * MSEC_PER_SEC));
> +		    secs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT));
>   	}
>   }
>   
> @@ -6283,9 +6283,9 @@ static int rbd_parse_param(struct fs_parameter *param,
>   		break;
>   	case Opt_lock_timeout:
>   		/* 0 is "wait forever" (i.e. infinite timeout) */
> -		if (result.uint_32 > INT_MAX / 1000)

Previously, the above line was verifying that the multiplication
done below would not overflow.  It was unrelated to whatever
msecs_to_jiffies() did.

> +		if (result.uint32 > INT_MAX / HZ)

Here you are assuming something about what secs_to_jiffies()
does.  It's a very reasonable assumption, but you are encoding
this in unrelated code, which you shouldn't do.

Just do the direct conversion as you've done above:

		if (result.uint32 > INT_MAX)

>   			goto out_of_range;
> -		opt->lock_timeout = msecs_to_jiffies(result.uint_32 * 1000);
> +		opt->lock_timeout = secs_to_jiffies(result.uint_32);

Unfortunately, secs_to_jiffies() does not implement the clamp
operation that msecs_to_jiffies() does.  If you look at
__msecs_to_jiffies() you see that the unsigned value provided
is limited to MAX_JIFFY_OFFSET if it's negative when interpreted
as a signed int (i.e., if its high bit is set).

I think the secs_to_jiffies() implementation could benefit
from the use of an overflow check.  This might not be
exactly right, but it gives the idea:

#define secs_to_jiffies(_secs)					\
	({							\
		unsigned long _result;				\
								\
		if (check_mul_overflow(_secs, HZ, &_result))	\
			_result = MAX_JIFFY_OFFSET;		\
		(_result);					\
	})

					-Alex


>   		break;
>   	case Opt_pool_ns:
>   		kfree(pctx->spec->pool_ns);
>
Re: [PATCH v4 1/2] rbd: convert timeouts to secs_to_jiffies()
Posted by Easwar Hariharan 11 months, 1 week ago 
On 3/2/2025 9:05 AM, Alex Elder wrote:
> On 2/28/25 10:22 PM, Easwar Hariharan wrote:
>> Commit b35108a51cf7 ("jiffies: Define secs_to_jiffies()") introduced
>> secs_to_jiffies().  As the value here is a multiple of 1000, use
>> secs_to_jiffies() instead of msecs_to_jiffies() to avoid the multiplication
>>
>> This is converted using scripts/coccinelle/misc/secs_to_jiffies.cocci with
>> the following Coccinelle rules:
>>
>> @depends on patch@ expression E; @@
>>
>> -msecs_to_jiffies(E * 1000)
>> +secs_to_jiffies(E)
>>
>> @depends on patch@ expression E; @@
>>
>> -msecs_to_jiffies(E * MSEC_PER_SEC)
>> +secs_to_jiffies(E)
>>
>> Change the check for range to check against HZ.
>>
>> Acked-by: Ilya Dryomov <idryomov@gmail.com>
>> Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com>
> 
> I think what you've done in the last hunk below should not be
> done that way.  I also suggest something to the (related, but
> not part of this series) secs_to_jiffies() implementation.
> 
>> ---
>>   drivers/block/rbd.c | 8 ++++----
>>   1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
>> index faafd7ff43d6ef53110ab3663cc7ac322214cc8c..1c406b17f3cee741b7bdd9f742958b3f1d5b1bbe 100644
>> --- a/drivers/block/rbd.c
>> +++ b/drivers/block/rbd.c
>> @@ -108,7 +108,7 @@ static int atomic_dec_return_safe(atomic_t *v)
>>   #define RBD_OBJ_PREFIX_LEN_MAX    64
>>     #define RBD_NOTIFY_TIMEOUT    5    /* seconds */
>> -#define RBD_RETRY_DELAY        msecs_to_jiffies(1000)
>> +#define RBD_RETRY_DELAY        secs_to_jiffies(1)
>>     /* Feature bits */
>>   @@ -4162,7 +4162,7 @@ static void rbd_acquire_lock(struct work_struct *work)
>>           dout("%s rbd_dev %p requeuing lock_dwork\n", __func__,
>>                rbd_dev);
>>           mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
>> -            msecs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT * MSEC_PER_SEC));
>> +            secs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT));
>>       }
>>   }
>>   @@ -6283,9 +6283,9 @@ static int rbd_parse_param(struct fs_parameter *param,
>>           break;
>>       case Opt_lock_timeout:
>>           /* 0 is "wait forever" (i.e. infinite timeout) */
>> -        if (result.uint_32 > INT_MAX / 1000)
> 
> Previously, the above line was verifying that the multiplication
> done below would not overflow.  It was unrelated to whatever
> msecs_to_jiffies() did.
> 
>> +        if (result.uint32 > INT_MAX / HZ)
> 
> Here you are assuming something about what secs_to_jiffies()
> does.  It's a very reasonable assumption, but you are encoding
> this in unrelated code, which you shouldn't do.
> 
> Just do the direct conversion as you've done above:
> 
>         if (result.uint32 > INT_MAX)
> 
>>               goto out_of_range;
>> -        opt->lock_timeout = msecs_to_jiffies(result.uint_32 * 1000);
>> +        opt->lock_timeout = secs_to_jiffies(result.uint_32);
> 
> Unfortunately, secs_to_jiffies() does not implement the clamp
> operation that msecs_to_jiffies() does.  If you look at
> __msecs_to_jiffies() you see that the unsigned value provided
> is limited to MAX_JIFFY_OFFSET if it's negative when interpreted
> as a signed int (i.e., if its high bit is set).
> 
> I think the secs_to_jiffies() implementation could benefit
> from the use of an overflow check.  This might not be
> exactly right, but it gives the idea:

Fair enough, let me explore this.

@Jens, @Andrew, can you drop the rbd and libceph patches from your respective
trees while I work this out?

Thanks,
Easwar (he/him)

> 
> #define secs_to_jiffies(_secs)                    \
>     ({                            \
>         unsigned long _result;                \
>                                 \
>         if (check_mul_overflow(_secs, HZ, &_result))    \
>             _result = MAX_JIFFY_OFFSET;        \
>         (_result);                    \
>     })
> 
>                     -Alex
> 
> 
>>           break;
>>       case Opt_pool_ns:
>>           kfree(pctx->spec->pool_ns);
>>
Re: [PATCH v4 1/2] rbd: convert timeouts to secs_to_jiffies()
Posted by Jens Axboe 11 months, 1 week ago 
On 3/3/25 11:13 AM, Easwar Hariharan wrote:
> @Jens, @Andrew, can you drop the rbd and libceph patches from your respective
> trees while I work this out?

Sure...

-- 
Jens Axboe

Patchew 2.1-devel-b67e4c2

© 2016 - 2026 Red Hat, Inc.