Re: [PATCH] irda: irda-usb: use msecs_to_jiffies for conversions
From: Joe Perches <joe@perches.com>
Date: 2015-05-19 14:32:21
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On Tue, 2015-05-19 at 12:51 +0200, Nicholas Mc Guire wrote:
Converting milliseconds to jiffies by "val * HZ / 1000" is technically is not a clean solution as it does not handle all corner cases correctly. By changing the conversion to use msecs_to_jiffies(val) conversion is correct in all cases. in the current code: mod_timer(&self->rx_defer_timer, jiffies + (10 * HZ / 1000)); for HZ < 100 (e.g. CONFIG_HZ == 64|32 in alpha) this effectively results in no delay at all.
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quoted hunk ↗ jump to hunk
diff --git a/drivers/net/irda/irda-usb.c b/drivers/net/irda/irda-usb.c
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quoted hunk ↗ jump to hunk
@@ -848,7 +848,9 @@ static void irda_usb_receive(struct urb *urb) * Jean II */ self->rx_defer_timer.function = irda_usb_rx_defer_expired; self->rx_defer_timer.data = (unsigned long) urb; - mod_timer(&self->rx_defer_timer, jiffies + (10 * HZ / 1000)); + mod_timer(&self->rx_defer_timer, + jiffies + (msecs_to_jiffies(10)));
The unnecessary () around msecs_to_jiffies could be removed.