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| author | Takashi Sakamoto <o-takashi@sakamocchi.jp> | 2017-04-11 13:33:18 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2017-04-12 15:34:21 +0200 |
| commit | f91c9d7610a2fe306273a83e2fd5351bceb85d28 (patch) | |
| tree | 83e477ea0a5ccdaa6f6e57e5ccbd83882c7a2d45 /sound/firewire/amdtp-stream.h | |
| parent | ALSA: hda: Add Geminilake id to SKL_PLUS (diff) | |
| download | linux-f91c9d7610a2fe306273a83e2fd5351bceb85d28.tar.xz linux-f91c9d7610a2fe306273a83e2fd5351bceb85d28.zip | |
ALSA: firewire-lib: cache maximum length of payload to reduce function calls
During packet streaming, maximum length of payload for isochronous packet
is invariable, therefore no need to recalculate. Current ALSA IEC 61883-1/6
engine calls a function to calculate it 8,000 or more times per second
for incoming packet processing.
This commit adds a member to have maximum length of payload into 'struct
amdtp_stream', to reduces the function calls. At first callback from
isochronous context, the length is calculated and stored for later
processing.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/firewire/amdtp-stream.h')
| -rw-r--r-- | sound/firewire/amdtp-stream.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/sound/firewire/amdtp-stream.h b/sound/firewire/amdtp-stream.h index 2bd4de4c7bb7..7e8831722821 100644 --- a/sound/firewire/amdtp-stream.h +++ b/sound/firewire/amdtp-stream.h @@ -110,6 +110,7 @@ struct amdtp_stream { int (*handle_packet)(struct amdtp_stream *s, unsigned int payload_quadlets, unsigned int cycle, unsigned int index); + unsigned int max_payload_length; /* For CIP headers. */ unsigned int source_node_id_field; |