[PATCH] firewire: ohci: add some "unlikely" hints

From: Stefan Richter
Date: Sat Aug 28 2010 - 08:22:50 EST


Mark evt_no_status and evt_bus_reset packet reception events as ones
that occur rarely.

Also, inline the debug flag check of log_ar_at_event(). [The same is
hopefully not necessary for log_irqs() which is only called at a single
site and hence auto-inlined by the compiler.]

Signed-off-by: Stefan Richter <stefanr@xxxxxxxxxxxxxxxxx>
---
drivers/firewire/ohci.c | 28 +++++++++++++++++-----------
1 file changed, 17 insertions(+), 11 deletions(-)

Index: b/drivers/firewire/ohci.c
===================================================================
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -398,14 +401,11 @@ static const char *phys[] = {
[0x2] = "self-id packet", [0x3] = "-reserved-",
};

-static void log_ar_at_event(char dir, int speed, u32 *header, int evt)
+static void _ar_at_event(char dir, int speed, u32 *header, int evt)
{
int tcode = header[0] >> 4 & 0xf;
char specific[12];

- if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
- return;
-
if (unlikely(evt >= ARRAY_SIZE(evts)))
evt = 0x1f;

@@ -456,6 +456,12 @@ static void log_ar_at_event(char dir, in
}
}

+static inline void log_ar_at_event(char dir, int speed, u32 *header, int evt)
+{
+ if (unlikely(param_debug & OHCI_PARAM_DEBUG_AT_AR))
+ _ar_at_event(dir, speed, header, evt);
+}
+
#else

#define param_debug 0
@@ -697,7 +703,7 @@ static __le32 *handle_ar_packet(struct a
* Several controllers, notably from NEC and VIA, forget to
* write ack_complete status at PHY packet reception.
*/
- if (evt == OHCI1394_evt_no_status &&
+ if (unlikely(evt == OHCI1394_evt_no_status) &&
(p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
p.ack = ACK_COMPLETE;

@@ -714,7 +720,7 @@ static __le32 *handle_ar_packet(struct a
* wrong generation. We set the correct generation for these
* at a slightly incorrect time (in bus_reset_tasklet).
*/
- if (evt == OHCI1394_evt_bus_reset) {
+ if (unlikely(evt == OHCI1394_evt_bus_reset)) {
if (!(ohci->quirks & QUIRK_RESET_PACKET))
ohci->request_generation = (p.header[2] >> 16) & 0xff;
} else if (ctx == &ohci->ar_request_ctx) {

--
Stefan Richter
-=====-==-=- =--- ===--
http://arcgraph.de/sr/

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