Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
The C6X SoCs contain several PLL controllers each with up to 16 clock outputs
feeding into the cores or peripheral clock domains. The hardware is very similar
to arm/mach-davinci clocks. This is still a work in progress which needs to be
updated once device tree clock binding changes shake out.
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
[msalter@redhat.com: add include of linux/module.h to sys_c6x.c]
Signed-off-by: Mark Salter <msalter@redhat.com>
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
The C6X architecture currently lacks an MMU so memory management is relatively
simple. There is no bus snooping between L2 and main memory but coherent DMA
memory is supported by making regions of main memory uncached. If such a region
is desired, it can be specified on the commandline with a "memdma=" argument.
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This is the basic devicetree support for C6X. Currently, four boards are
supported. Each one uses a different SoC part. Two of the four supported
SoCs are multicore. One with 3 cores and the other with 6 cores. There is
no coherency between the core-level caches, so SMP is not an option. It is
possible to run separate kernel instances on the various cores. There is
currently no C6X bootloader support for device trees so we build in the DTB
for now.
There are some interesting twists to the hardware which are of note for device
tree support. Each core has its own interrupt controller which is controlled
by special purpose core registers. This core controller provides 12 general
purpose prioritized interrupt sources. Each core is contained within a
hardware "module" which provides L1 and L2 caches, power control, and another
interrupt controller which cascades into the core interrupt controller. These
core module functions are controlled by memory mapped registers. The addresses
for these registers are the same for each core. That is, when coreN accesses
a module-level MMIO register at a given address, it accesses the register for
coreN even though other cores would use the same address to access the register
in the module containing those cores. Other hardware modules (timers, enet, etc)
which are memory mapped can be accessed by all cores.
The timers need some further explanation for multicore SoCs. Even though all
timer control registers are visible to all cores, interrupt routing or other
considerations may make a given timer more suitable for use by a core than
some other timer. Because of this and the desire to have the same image run
on more than one core, the timer nodes have a "ti,core-mask" property which
is used by the driver to scan for a suitable timer to use.
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
This patch provides the early boot code for C6X architecture. There is a
16 entry vector table which is used to direct reset and interrupt events. The
vector table entries contain a small amount of code (maximum of 8 opcodes)
which simply branches to the actual event handling code.
The head.S code simply clears BSS, setups up a few control registers, and calls
machine_init followed by start_kernel. The machine_init code in setup.c does
the early flat tree parsing (memory, commandline, etc). At setup_arch time, the
code does the usual memory setup and minimally scans the devicetree for any
needed information.
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
asm-generic/page.h had several problems when used with a non-zero PAGE_OFFSET.
This patch adds a default ARCH_PFN_OFFSET and fixes the __va, __pa, and
pfn_valid macros to work with non-zero PAGE_OFFSETs.
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
The existing __strnlen_user macro simply resolved to strnlen. However, the
count returned by strnlen_user should include the NULL byte. This patch
fixes the __strnlen_user macro to include the NULL byte in the count.
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
* git://github.com/davem330/net:
net: fix typos in Documentation/networking/scaling.txt
bridge: leave carrier on for empty bridge
netfilter: Use proper rwlock init function
tcp: properly update lost_cnt_hint during shifting
tcp: properly handle md5sig_pool references
macvlan/macvtap: Fix unicast between macvtap interfaces in bridge mode
In summary, this DMI quirk uses the _CRS info by default for the ASUS
M2V-MX SE by turning on `pci=use_crs` and is similar to the quirk
added by commit 2491762cfb ("x86/PCI: use host bridge _CRS info on
ASRock ALiveSATA2-GLAN") whose commit message should be read for further
information.
Since commit 3e3da00c01 ("x86/pci: AMD one chain system to use pci
read out res") Linux gives the following oops:
parport0: PC-style at 0x378, irq 7 [PCSPP,TRISTATE]
HDA Intel 0000:20:01.0: PCI INT A -> GSI 17 (level, low) -> IRQ 17
HDA Intel 0000:20:01.0: setting latency timer to 64
BUG: unable to handle kernel paging request at ffffc90011c08000
IP: [<ffffffffa0578402>] azx_probe+0x3ad/0x86b [snd_hda_intel]
PGD 13781a067 PUD 13781b067 PMD 1300ba067 PTE 800000fd00000173
Oops: 0009 [#1] SMP
last sysfs file: /sys/module/snd_pcm/initstate
CPU 0
Modules linked in: snd_hda_intel(+) snd_hda_codec snd_hwdep snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event tpm_tis tpm snd_seq tpm_bios psmouse parport_pc snd_timer snd_seq_device parport processor evdev snd i2c_viapro thermal_sys amd64_edac_mod k8temp i2c_core soundcore shpchp pcspkr serio_raw asus_atk0110 pci_hotplug edac_core button snd_page_alloc edac_mce_amd ext3 jbd mbcache sha256_generic cryptd aes_x86_64 aes_generic cbc dm_crypt dm_mod raid1 md_mod usbhid hid sg sd_mod crc_t10dif sr_mod cdrom ata_generic uhci_hcd sata_via pata_via libata ehci_hcd usbcore scsi_mod via_rhine mii nls_base [last unloaded: scsi_wait_scan]
Pid: 1153, comm: work_for_cpu Not tainted 2.6.37-1-amd64 #1 M2V-MX SE/System Product Name
RIP: 0010:[<ffffffffa0578402>] [<ffffffffa0578402>] azx_probe+0x3ad/0x86b [snd_hda_intel]
RSP: 0018:ffff88013153fe50 EFLAGS: 00010286
RAX: ffffc90011c08000 RBX: ffff88013029ec00 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246
RBP: ffff88013341d000 R08: 0000000000000000 R09: 0000000000000040
R10: 0000000000000286 R11: 0000000000003731 R12: ffff88013029c400
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88013341d090
FS: 0000000000000000(0000) GS:ffff8800bfc00000(0000) knlGS:00000000f7610ab0
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffffc90011c08000 CR3: 0000000132f57000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process work_for_cpu (pid: 1153, threadinfo ffff88013153e000, task ffff8801303c86c0)
Stack:
0000000000000005 ffffffff8123ad65 00000000000136c0 ffff88013029c400
ffff8801303c8998 ffff88013341d000 ffff88013341d090 ffff8801322d9dc8
ffff88013341d208 0000000000000000 0000000000000000 ffffffff811ad232
Call Trace:
[<ffffffff8123ad65>] ? __pm_runtime_set_status+0x162/0x186
[<ffffffff811ad232>] ? local_pci_probe+0x49/0x92
[<ffffffff8105afc5>] ? do_work_for_cpu+0x0/0x1b
[<ffffffff8105afc5>] ? do_work_for_cpu+0x0/0x1b
[<ffffffff8105afd0>] ? do_work_for_cpu+0xb/0x1b
[<ffffffff8105fd3f>] ? kthread+0x7a/0x82
[<ffffffff8100a824>] ? kernel_thread_helper+0x4/0x10
[<ffffffff8105fcc5>] ? kthread+0x0/0x82
[<ffffffff8100a820>] ? kernel_thread_helper+0x0/0x10
Code: f4 01 00 00 ef 31 f6 48 89 df e8 29 dd ff ff 85 c0 0f 88 2b 03 00 00 48 89 ef e8 b4 39 c3 e0 8b 7b 40 e8 fc 9d b1 e0 48 8b 43 38 <66> 8b 10 66 89 14 24 8b 43 14 83 e8 03 83 f8 01 77 32 31 d2 be
RIP [<ffffffffa0578402>] azx_probe+0x3ad/0x86b [snd_hda_intel]
RSP <ffff88013153fe50>
CR2: ffffc90011c08000
---[ end trace 8d1f3ebc136437fd ]---
Trusting the ACPI _CRS information (`pci=use_crs`) fixes this problem.
$ dmesg | grep -i crs # with the quirk
PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug
The match has to be against the DMI board entries though since the vendor entries are not populated.
DMI: System manufacturer System Product Name/M2V-MX SE, BIOS 0304 10/30/2007
This quirk should be removed when `pci=use_crs` is enabled for machines
from 2006 or earlier or some other solution is implemented.
Using coreboot [1] with this board the problem does not exist but this
quirk also does not affect it either. To be safe though the check is
tightened to only take effect when the BIOS from American Megatrends is
used.
15:13 < ruik> but coreboot does not need that
15:13 < ruik> because i have there only one root bus
15:13 < ruik> the audio is behind a bridge
$ sudo dmidecode
BIOS Information
Vendor: American Megatrends Inc.
Version: 0304
Release Date: 10/30/2007
[1] http://www.coreboot.org/
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=30552
Cc: stable@kernel.org (2.6.34)
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: x86@kernel.org
Signed-off-by: Paul Menzel <paulepanter@users.sourceforge.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The second hunk fixes rps_sock_flow_table but has to re-wrap the paragraph.
Signed-off-by: Benjamin Poirier <benjamin.poirier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This resolves a regression seen by some users of bridging.
Some users use the bridge like a dummy device.
They expect to be able to put an IPv6 address on the device
with no ports attached. Although there are better ways of doing
this, there is no reason to not allow it.
Note: the bridge still will reflect the state of ports in the
bridge if there are any added.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace the open coded initialization with the init function.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Hans Schillstrom <hans.schillstrom@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://bedivere.hansenpartnership.com/git/scsi-rc-fixes-2.6:
[SCSI] libsas: fix panic when single phy is disabled on a wide port
[SCSI] qla2xxx: Fix crash in qla2x00_abort_all_cmds() on unload
This reverts commit 71c86ce597.
The 21UX2 does have touchstrips, but they are in a somewhat-
hidden location.
Signed-off-by: Jason Gerecke <killertofu@gmail.com>
Acked-by: Ping Cheng <pinglinux@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
lost_skb_hint is used by tcp_mark_head_lost() to mark the first unhandled skb.
lost_cnt_hint is the number of packets or sacked packets before the lost_skb_hint;
When shifting a skb that is before the lost_skb_hint, if tcp_is_fack() is ture,
the skb has already been counted in the lost_cnt_hint; if tcp_is_fack() is false,
tcp_sacktag_one() will increase the lost_cnt_hint. So tcp_shifted_skb() does not
need to adjust the lost_cnt_hint by itself. When shifting a skb that is equal to
lost_skb_hint, the shifted packets will not be counted by tcp_mark_head_lost().
So tcp_shifted_skb() should adjust the lost_cnt_hint even tcp_is_fack(tp) is true.
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp_v4_clear_md5_list() assumes that multiple tcp md5sig peers
only hold one reference to md5sig_pool. but tcp_v4_md5_do_add()
increases use count of md5sig_pool for each peer. This patch
makes tcp_v4_md5_do_add() only increases use count for the first
tcp md5sig peer.
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Packets should always be forwarded to the lowerdev using dev_forward_skb.
vlan->forward is for packets being forwarded directly to another macvlan/
macvtap device (used for multicast in bridge mode).
Reported-and-tested-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: David Ward <david.ward@ll.mit.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://github.com/davem330/net:
pch_gbe: Fixed the issue on which a network freezes
pch_gbe: Fixed the issue on which PC was frozen when link was downed.
make PACKET_STATISTICS getsockopt report consistently between ring and non-ring
net: xen-netback: correctly restart Tx after a VM restore/migrate
bonding: properly stop queuing work when requested
can bcm: fix incomplete tx_setup fix
RDSRDMA: Fix cleanup of rds_iw_mr_pool
net: Documentation: Fix type of variables
ibmveth: Fix oops on request_irq failure
ipv6: nullify ipv6_ac_list and ipv6_fl_list when creating new socket
cxgb4: Fix EEH on IBM P7IOC
can bcm: fix tx_setup off-by-one errors
MAINTAINERS: tehuti: Alexander Indenbaum's address bounces
dp83640: reduce driver noise
ptp: fix L2 event message recognition
* 'fix/asoc' of git://github.com/tiwai/sound:
ASoC: omap_mcpdm_remove cannot be __devexit
ASoC: Fix setting update bits for WM8753_LADC and WM8753_RADC
ASoC: use a valid device for dev_err() in Zylonite
Add the ability to disable PCI-E MPS turning and using the BIOS
configured MPS defaults. Due to the number of issues recently
discovered on some x86 chipsets, make this the default behavior.
Also, add the option for peer to peer DMA MPS configuration. Peer to
peer DMA is outside the scope of this patch, but MPS configuration could
prevent it from working by having the MPS on one root port different
than the MPS on another. To work around this, simply make the system
wide MPS the smallest possible value (128B).
Signed-off-by: Jon Mason <mason@myri.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Most asics just use the hw default value which requires
no explicit programming. For those that need a different
value, the vbios will program it properly. As such,
there's no need to program these registers explicitly
in the driver. Changing MC_SHARED_CHREMAP requires a reload
of all data in vram otherwise its contents will be scambled.
Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=40103
v2: drop now unused channel_remap functions.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
We found that adding load, Rx data sometimes drops.(with DMA transfer mode)
The cause is that before starting Rx-DMA processing, Tx-DMA processing starts.
This causes FIFO overrun occurs.
This patch fixes the issue by modifying FIFO tx-threshold and DMA descriptor
size like below.
Current this patch
Rx-descriptor 4Byte+12Byte*341 --> 12Byte*340-4Byte-12Byte
Rx-threshold (Not modified)
Tx-descriptor 4Byte+12Byte*341 --> 16Byte-12Byte*340
Rx-threshold 12Byte --> 2Byte
Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Add recovery processing in case FIFO overrun error occurs with DMA transfer mode.
Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
We found Rx data sometimes drops.(with non-DMA transfer mode)
The cause is read complete condition is not true.
This patch fixes the issue.
Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
During processing 1 command/data series,
SSN should keep LOW.
However, currently, SSN becomes HIGH.
This patch fixes the issue.
Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Currently, in case of reading date from SPI flash,
command is sent twice.
The cause is that tx-memory clear processing is missing .
This patch adds the tx-momory clear processing.
Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Commit 2a7fade7e0 ("hwmon: lis3: Power on corrections") caused a
regression on HP laptops with 8bit chip. Writing CTRL2_BOOT_8B bit seems
clearing the BIOS setup, and no proper interrupt for DriveGuard will be
triggered any more.
Since the init code there is basically only for embedded devices, put a
pdata check so that the problematic initialization will be skipped for
hp_accel stuff.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: Eric Piel <eric.piel@tremplin-utc.net>
Cc: Samu Onkalo <samu.p.onkalo@nokia.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Simon Kirby reported that on his RAID setup with idedisk underneath
the box OOMs after a couple of days of runtime. Running with
CONFIG_DEBUG_KMEMLEAK pointed to idedisk_prep_fn() which unconditionally
allocates an ide_cmd struct. However, ide_requeue_and_plug() can be
called more than once per request, either from the request issue or the
IRQ handler path and do blk_peek_request() ends up in idedisk_prep_fn()
repeatedly, allocating a struct ide_cmd everytime and "forgetting" the
previous pointer.
Make sure the code reuses the old allocated chunk.
Reported-and-tested-by: Simon Kirby <sim@hostway.ca>
Cc: <stable@kernel.org> [ 39.x, 3.0.x ]
Link: http://marc.info/?l=linux-kernel&m=131667641517919
Link: http://lkml.kernel.org/r/20110922072643.GA27232@hostway.ca
Signed-off-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The pch_gbe driver has an issue which a network stops,
when receiving traffic is high.
In the case, The link down and up are necessary to return a network.
This patch fixed this issue.
Signed-off-by: Toshiharu Okada <toshiharu-linux@dsn.okisemi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a link was downed during network use,
there is an issue on which PC freezes.
This patch fixed this issue.
Signed-off-by: Toshiharu Okada <toshiharu-linux@dsn.okisemi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a minor change.
Up until kernel 2.6.32, getsockopt(fd, SOL_PACKET, PACKET_STATISTICS,
...) would return total and dropped packets since its last invocation. The
introduction of socket queue overflow reporting [1] changed drop
rate calculation in the normal packet socket path, but not when using a
packet ring. As a result, the getsockopt now returns different statistics
depending on the reception method used. With a ring, it still returns the
count since the last call, as counts are incremented in tpacket_rcv and
reset in getsockopt. Without a ring, it returns 0 if no drops occurred
since the last getsockopt and the total drops over the lifespan of
the socket otherwise. The culprit is this line in packet_rcv, executed
on a drop:
drop_n_acct:
po->stats.tp_drops = atomic_inc_return(&sk->sk_drops);
As it shows, the new drop number it taken from the socket drop counter,
which is not reset at getsockopt. I put together a small example
that demonstrates the issue [2]. It runs for 10 seconds and overflows
the queue/ring on every odd second. The reported drop rates are:
ring: 16, 0, 16, 0, 16, ...
non-ring: 0, 15, 0, 30, 0, 46, 0, 60, 0 , 74.
Note how the even ring counts monotonically increase. Because the
getsockopt adds tp_drops to tp_packets, total counts are similarly
reported cumulatively. Long story short, reinstating the original code, as
the below patch does, fixes the issue at the cost of additional per-packet
cycles. Another solution that does not introduce per-packet overhead
is be to keep the current data path, record the value of sk_drops at
getsockopt() at call N in a new field in struct packetsock and subtract
that when reporting at call N+1. I'll be happy to code that, instead,
it's just more messy.
[1] http://patchwork.ozlabs.org/patch/35665/
[2] http://kernel.googlecode.com/files/test-packetsock-getstatistics.c
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>