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| author | Thomas Zimmermann <tzimmermann@suse.de> | 2025-10-13 09:19:19 +0200 |
|---|---|---|
| committer | Thomas Zimmermann <tzimmermann@suse.de> | 2025-10-13 09:19:19 +0200 |
| commit | 9b966ae42235a88eaea714be09ff3d698535bdfe (patch) | |
| tree | 7470df78fb74fdfda1f773feb3822c1c9ab38616 /drivers/usb/mon/mon_bin.c | |
| parent | 5385871282e5c2831c226d32cf2ce26b45a7b164 (diff) | |
| parent | 3a8660878839faadb4f1a6dd72c3179c1df56787 (diff) | |
Merge drm/drm-next into drm-misc-next
Updating drm-misc-next to the state of v6.18-rc1.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Diffstat (limited to 'drivers/usb/mon/mon_bin.c')
| -rw-r--r-- | drivers/usb/mon/mon_bin.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/drivers/usb/mon/mon_bin.c b/drivers/usb/mon/mon_bin.c index c93b43f5bc46..e713fc5964b1 100644 --- a/drivers/usb/mon/mon_bin.c +++ b/drivers/usb/mon/mon_bin.c @@ -68,18 +68,20 @@ * The magic limit was calculated so that it allows the monitoring * application to pick data once in two ticks. This way, another application, * which presumably drives the bus, gets to hog CPU, yet we collect our data. - * If HZ is 100, a 480 mbit/s bus drives 614 KB every jiffy. USB has an - * enormous overhead built into the bus protocol, so we need about 1000 KB. + * + * Originally, for a 480 Mbit/s bus this required a buffer of about 1 MB. For + * modern 20 Gbps buses, this value increases to over 50 MB. The maximum + * buffer size is set to 64 MiB to accommodate this. * * This is still too much for most cases, where we just snoop a few * descriptor fetches for enumeration. So, the default is a "reasonable" - * amount for systems with HZ=250 and incomplete bus saturation. + * amount for typical, low-throughput use cases. * * XXX What about multi-megabyte URBs which take minutes to transfer? */ -#define BUFF_MAX CHUNK_ALIGN(1200*1024) -#define BUFF_DFL CHUNK_ALIGN(300*1024) -#define BUFF_MIN CHUNK_ALIGN(8*1024) +#define BUFF_MAX CHUNK_ALIGN(64*1024*1024) +#define BUFF_DFL CHUNK_ALIGN(300*1024) +#define BUFF_MIN CHUNK_ALIGN(8*1024) /* * The per-event API header (2 per URB). |