[PATCH] Add errseq_t documentation to the tree
- Add it under 'Core API' because I think that's where it lives. - Promote the header to a more prominent header type, otherwise we get three entries in the table of contents. - Reformat the table to look nicer and be a little more proportional in terms of horizontal width per bit (the SF bit is still disproportionately large, but there's no way to fix that). Signed-off-by: Matthew Wilcox diff --git a/Documentation/core-api/index.rst b/Documentation/core-api/index.rst index eb16ba30aeb6..b8ec120c24f9 100644 --- a/Documentation/core-api/index.rst +++ b/Documentation/core-api/index.rst @@ -22,6 +22,7 @@ Core utilities flexible-arrays librs genalloc + ../errseq Interfaces for kernel debugging === diff --git a/Documentation/errseq.rst b/Documentation/errseq.rst index 4c29bd5afbc5..7c3ac9639ebf 100644 --- a/Documentation/errseq.rst +++ b/Documentation/errseq.rst @@ -1,5 +1,7 @@ += The errseq_t datatype = + An errseq_t is a way of recording errors in one place, and allowing any number of "subscribers" to tell whether it has changed since a previous point where it was sampled. @@ -21,12 +23,13 @@ a flag to tell whether the value has been sampled since a new value was recorded. That allows us to avoid bumping the counter if no one has sampled it since the last time an error was recorded. -Thus we end up with a value that looks something like this:: +Thus we end up with a value that looks something like this: -bit: 31..131211..0 -+-+++ -| counter | SF | errno | -+-+++ ++--+++ +| 31..13 | 12 | 11..0 | ++--+++ +| counter | SF | errno | ++--+++ The general idea is for "watchers" to sample an errseq_t value and keep it as a running cursor. That value can later be used to tell whether @@ -42,6 +45,7 @@ has ever been an error set since it was first initialized. API usage = + Let me tell you a story about a worker drone. Now, he's a good worker overall, but the company is a little...management heavy. He has to report to 77 supervisors today, and tomorrow the "big boss" is coming in @@ -125,6 +129,7 @@ not usable by anyone else. Serializing errseq_t cursor updates === + Note that the errseq_t API does not protect the errseq_t cursor during a check_and_advance_operation. Only the canonical error code is handled atomically. In a situation where more than one task might be using the -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] Add errseq_t documentation to the tree
On Fri, 2017-12-22 at 05:04 -0800, Matthew Wilcox wrote: > - Add it under 'Core API' because I think that's where it lives. > - Promote the header to a more prominent header type, otherwise we get three >entries in the table of contents. > - Reformat the table to look nicer and be a little more proportional in >terms of horizontal width per bit (the SF bit is still disproportionately >large, but there's no way to fix that). > > Signed-off-by: Matthew Wilcox > > diff --git a/Documentation/core-api/index.rst > b/Documentation/core-api/index.rst > index eb16ba30aeb6..b8ec120c24f9 100644 > --- a/Documentation/core-api/index.rst > +++ b/Documentation/core-api/index.rst > @@ -22,6 +22,7 @@ Core utilities > flexible-arrays > librs > genalloc > + ../errseq > Should we also move the file into core-api/ dir? > > Interfaces for kernel debugging > === > diff --git a/Documentation/errseq.rst b/Documentation/errseq.rst > index 4c29bd5afbc5..7c3ac9639ebf 100644 > --- a/Documentation/errseq.rst > +++ b/Documentation/errseq.rst > @@ -1,5 +1,7 @@ > += > The errseq_t datatype > = > + > An errseq_t is a way of recording errors in one place, and allowing any > number of "subscribers" to tell whether it has changed since a previous > point where it was sampled. > @@ -21,12 +23,13 @@ a flag to tell whether the value has been sampled since a > new value was > recorded. That allows us to avoid bumping the counter if no one has > sampled it since the last time an error was recorded. > > -Thus we end up with a value that looks something like this:: > +Thus we end up with a value that looks something like this: > > -bit: 31..131211..0 > -+-+++ > -| counter | SF | errno | > -+-+++ > ++--+++ > +| 31..13 | 12 | 11..0 | > ++--+++ > +| counter | SF | errno | > ++--+++ > > The general idea is for "watchers" to sample an errseq_t value and keep > it as a running cursor. That value can later be used to tell whether > @@ -42,6 +45,7 @@ has ever been an error set since it was first initialized. > > API usage > = > + > Let me tell you a story about a worker drone. Now, he's a good worker > overall, but the company is a little...management heavy. He has to > report to 77 supervisors today, and tomorrow the "big boss" is coming in > @@ -125,6 +129,7 @@ not usable by anyone else. > > Serializing errseq_t cursor updates > === > + > Note that the errseq_t API does not protect the errseq_t cursor during a > check_and_advance_operation. Only the canonical error code is handled > atomically. In a situation where more than one task might be using the Thanks for the cleanup, looks good. Reviewed-by: Jeff Layton -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] Add errseq_t documentation to the tree
On Fri, Dec 22, 2017 at 08:29:34AM -0500, Jeff Layton wrote: > > +++ b/Documentation/core-api/index.rst > > @@ -22,6 +22,7 @@ Core utilities > > flexible-arrays > > librs > > genalloc > > + ../errseq > > > > Should we also move the file into core-api/ dir? I was wondering the same thing. I'll do a v2. I was also thinking about including the kernel-doc from lib/errseq.c into this file. Seems like the logical thing to do. > Reviewed-by: Jeff Layton Merci! -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH v2] errseq: Add to documentation tree
From: Matthew Wilcox
- Move errseq.rst into core-api
- Add errseq to the core-api index
- Promote the header to a more prominent header type, otherwise we get three
entries in the table of contents.
- Reformat the table to look nicer and be a little more proportional in
terms of horizontal width per bit (the SF bit is still disproportionately
large, but there's no way to fix that).
- Include errseq kernel-doc in the errseq.rst
- Neaten some kernel-doc markup
Signed-off-by: Matthew Wilcox
Reviewed-by: Jeff Layton
---
Documentation/{ => core-api}/errseq.rst | 20 +-
Documentation/core-api/index.rst| 1 +
include/linux/errseq.h | 2 +-
lib/errseq.c| 37 +++--
4 files changed, 38 insertions(+), 22 deletions(-)
rename Documentation/{ => core-api}/errseq.rst (92%)
diff --git a/Documentation/errseq.rst b/Documentation/core-api/errseq.rst
similarity index 92%
rename from Documentation/errseq.rst
rename to Documentation/core-api/errseq.rst
index 4c29bd5afbc5..ff332e272405 100644
--- a/Documentation/errseq.rst
+++ b/Documentation/core-api/errseq.rst
@@ -1,5 +1,7 @@
+=
The errseq_t datatype
=
+
An errseq_t is a way of recording errors in one place, and allowing any
number of "subscribers" to tell whether it has changed since a previous
point where it was sampled.
@@ -21,12 +23,13 @@ a flag to tell whether the value has been sampled since a
new value was
recorded. That allows us to avoid bumping the counter if no one has
sampled it since the last time an error was recorded.
-Thus we end up with a value that looks something like this::
+Thus we end up with a value that looks something like this:
-bit: 31..131211..0
-+-+++
-| counter | SF | errno |
-+-+++
++--+++
+| 31..13 | 12 | 11..0 |
++--+++
+| counter | SF | errno |
++--+++
The general idea is for "watchers" to sample an errseq_t value and keep
it as a running cursor. That value can later be used to tell whether
@@ -42,6 +45,7 @@ has ever been an error set since it was first initialized.
API usage
=
+
Let me tell you a story about a worker drone. Now, he's a good worker
overall, but the company is a little...management heavy. He has to
report to 77 supervisors today, and tomorrow the "big boss" is coming in
@@ -125,6 +129,7 @@ not usable by anyone else.
Serializing errseq_t cursor updates
===
+
Note that the errseq_t API does not protect the errseq_t cursor during a
check_and_advance_operation. Only the canonical error code is handled
atomically. In a situation where more than one task might be using the
@@ -147,3 +152,8 @@ errseq_check_and_advance after taking the lock. e.g.::
That avoids the spinlock in the common case where nothing has changed
since the last time it was checked.
+
+Functions
+=
+
+.. kernel-doc:: lib/errseq.c
diff --git a/Documentation/core-api/index.rst b/Documentation/core-api/index.rst
index eb16ba30aeb6..b226d05df1c3 100644
--- a/Documentation/core-api/index.rst
+++ b/Documentation/core-api/index.rst
@@ -22,6 +22,7 @@ Core utilities
flexible-arrays
librs
genalloc
+ errseq
Interfaces for kernel debugging
===
diff --git a/include/linux/errseq.h b/include/linux/errseq.h
index 6ffae9c5052d..fc270768 100644
--- a/include/linux/errseq.h
+++ b/include/linux/errseq.h
@@ -1,6 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
- * See Documentation/errseq.rst and lib/errseq.c
+ * See Documentation/core-api/errseq.rst and lib/errseq.c
*/
#ifndef _LINUX_ERRSEQ_H
#define _LINUX_ERRSEQ_H
diff --git a/lib/errseq.c b/lib/errseq.c
index 79cc66897db4..df782418b333 100644
--- a/lib/errseq.c
+++ b/lib/errseq.c
@@ -46,14 +46,14 @@
* @eseq: errseq_t field that should be set
* @err: error to set (must be between -1 and -MAX_ERRNO)
*
- * This function sets the error in *eseq, and increments the sequence counter
+ * This function sets the error in @eseq, and increments the sequence counter
* if the last sequence was sampled at some point in the past.
*
* Any error set will always overwrite an existing error.
*
- * We do return the latest value here, primarily for debugging purposes. The
- * return value should not be used as a previously sampled value in later calls
- * as it will not have the SEEN flag set.
+ * Return: The previous value, primarily for debugging purposes. The
+ * return value should not be used as a previously sampled value in later
+ *
Re: [PATCH 05/11] media: dvb_vb2: fix a warning about streamoff logic
Em Thu, 21 Dec 2017 14:18:04 -0200 Mauro Carvalho Chehab escreveu: > The streamoff logic is causing those warnings: > > WARNING: CPU: 3 PID: 3382 at drivers/media/v4l2-core/videobuf2-core.c:1652 > __vb2_queue_cancel+0x177/0x250 [videobuf2_core] > Modules linked in: bnep fuse xt_CHECKSUM iptable_mangle tun ebtable_filter > ebtables ip6table_filter ip6_tables xt_physdev br_netfilter bluetooth bridge > rfkill ecdh_generic stp llc nf_log_ipv4 nf_log_common xt_LOG xt_conntrack > ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_conntrack_ipv4 > nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack libcrc32c sunrpc vfat fat > snd_hda_codec_hdmi rc_dib0700_nec i915 rc_pinnacle_pctv_hd em28xx_rc a8293 > ts2020 m88ds3103 i2c_mux em28xx_dvb dib8000 dvb_usb_dib0700 dib0070 dib7000m > dib0090 dvb_usb dvb_core uvcvideo snd_usb_audio videobuf2_v4l2 dib3000mc > videobuf2_vmalloc videobuf2_memops dibx000_common videobuf2_core rc_core > snd_usbmidi_lib snd_rawmidi em28xx tveeprom v4l2_common videodev media > intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp snd_hda_intel > kvm_intel snd_hda_codec kvm snd_hwdep snd_hda_core snd_seq irqbypass > crct10dif_pclmul crc32_pclmul i2c_algo_bit ghash_clmulni_intel snd_seq_device > drm_kms_helper snd_pcm intel_cstate intel_uncore snd_timer tpm_tis drm > mei_wdt iTCO_wdt iTCO_vendor_support tpm_tis_core snd intel_rapl_perf mei_me > mei tpm i2c_i801 soundcore lpc_ich video binfmt_misc hid_logitech_hidpp > hid_logitech_dj e1000e crc32c_intel ptp pps_core analog gameport joydev > CPU: 3 PID: 3382 Comm: lt-dvbv5-zap Not tainted 4.14.0+ #3 > Hardware name: /D53427RKE, BIOS > RKPPT10H.86A.0048.2017.0506.1545 05/06/2017 > task: 94b93bbe1e40 task.stack: b7a98320c000 > RIP: 0010:__vb2_queue_cancel+0x177/0x250 [videobuf2_core] > RSP: 0018:b7a98320fd40 EFLAGS: 00010202 > RAX: 0001 RBX: 94b92ff72428 RCX: > RDX: 0001 RSI: 0001 RDI: 94b92ff72428 > RBP: b7a98320fd68 R08: 94b92ff725d8 R09: b7a98320fcc8 > R10: 94b978003d98 R11: 94b92ff72428 R12: 94b92ff72428 > R13: 0282 R14: 94b92059ae20 R15: dead0100 > FS: () GS:94b99e38() knlGS: > CS: 0010 DS: ES: CR0: 80050033 > CR2: 555953007d70 CR3: 00012be09004 CR4: 001606e0 > Call Trace: > vb2_core_streamoff+0x28/0x90 [videobuf2_core] > dvb_vb2_stream_off+0xd1/0x150 [dvb_core] > dvb_dvr_release+0x114/0x120 [dvb_core] > __fput+0xdf/0x1e0 > fput+0xe/0x10 > task_work_run+0x94/0xc0 > do_exit+0x2dc/0xba0 > do_group_exit+0x47/0xb0 > SyS_exit_group+0x14/0x20 > entry_SYSCALL_64_fastpath+0x1a/0xa5 > RIP: 0033:0x7f775e931ed8 > RSP: 002b:7fff07019d68 EFLAGS: 0246 ORIG_RAX: 00e7 > RAX: ffda RBX: 01d02690 RCX: 7f775e931ed8 > RDX: 0001 RSI: 003c RDI: 0001 > RBP: 7fff0701a500 R08: 00e7 R09: ff70 > R10: 7f775e854dd8 R11: 0246 R12: > R13: 035fa000 R14: 000a R15: 000a > Code: 00 00 04 74 1c 44 89 e8 49 83 c5 01 41 39 84 24 88 01 00 00 77 8a 5b > 41 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 bb fd ff ff eb da <0f> ff 41 8b b4 > 24 88 01 00 00 85 f6 74 34 bb 01 00 00 00 eb 10 > > There are actually two issues here: > > 1) list_del() should be called when changing the buffer state; > > 2) The logic with marks the buffers as done is at the wrong place. > > Signed-off-by: Mauro Carvalho Chehab I ended by sending a wrong version. The one I sent causes a list corruption, as it deletes a queued value without marking the buffer as done: [ 627.233534] list_del corruption, a0aa01182e20->next is LIST_POISON1 (dead0100) Regards, Mauro [PATCH] media: dvb_vb2: fix a warning about streamoff logic The streamoff logic is causing those warnings: WARNING: CPU: 3 PID: 3382 at drivers/media/v4l2-core/videobuf2-core.c:1652 __vb2_queue_cancel+0x177/0x250 [videobuf2_core] Modules linked in: bnep fuse xt_CHECKSUM iptable_mangle tun ebtable_filter ebtables ip6table_filter ip6_tables xt_physdev br_netfilter bluetooth bridge rfkill ecdh_generic stp llc nf_log_ipv4 nf_log_common xt_LOG xt_conntrack ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack libcrc32c sunrpc vfat fat snd_hda_codec_hdmi rc_dib0700_nec i915 rc_pinnacle_pctv_hd em28xx_rc a8293 ts2020 m88ds3103 i2c_mux em28xx_dvb dib8000 dvb_usb_dib0700 dib0070 dib7000m dib0090 dvb_usb dvb_core uvcvideo snd_usb_audio videobuf2_v4l2 dib3000mc videobuf2_vmalloc videobuf2_memops dibx000_common videobuf2_core rc_core snd_usbmidi_lib snd_rawmidi em28xx tveeprom v4l2_common videodev media intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp snd_hda_intel kvm_intel snd_hda_codec kvm snd_h
[PATCH] doc: md: Fix a file name to md-fault.c in fault-injection.txt
drivers/md/faulty.c has been renamed to md-faulty.c after following commit merged int to the main line. 935fe0983e09f4f7331ebf5ea4ae2124f6e9f9e8 . But the file name in fault-injection.txt has not been changed. Now the actual file name and document are in sync. Signed-off-by: Masanari Iida --- Documentation/fault-injection/fault-injection.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.txt index 918972babcd8..1c0bfbbf7869 100644 --- a/Documentation/fault-injection/fault-injection.txt +++ b/Documentation/fault-injection/fault-injection.txt @@ -1,7 +1,7 @@ Fault injection capabilities infrastructure === -See also drivers/md/faulty.c and "every_nth" module option for scsi_debug. +See also drivers/md/md-faulty.c and "every_nth" module option for scsi_debug. Available fault injection capabilities -- 2.15.1.433.g936d1b989416 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v2] errseq: Add to documentation tree
On 12/22/2017 06:32 AM, Matthew Wilcox wrote:
> From: Matthew Wilcox
>
> - Move errseq.rst into core-api
> - Add errseq to the core-api index
> - Promote the header to a more prominent header type, otherwise we get three
>entries in the table of contents.
> - Reformat the table to look nicer and be a little more proportional in
>terms of horizontal width per bit (the SF bit is still disproportionately
>large, but there's no way to fix that).
> - Include errseq kernel-doc in the errseq.rst
> - Neaten some kernel-doc markup
>
> Signed-off-by: Matthew Wilcox
> Reviewed-by: Jeff Layton
> ---
> Documentation/{ => core-api}/errseq.rst | 20 +-
> Documentation/core-api/index.rst| 1 +
> include/linux/errseq.h | 2 +-
> lib/errseq.c| 37
> +++--
> 4 files changed, 38 insertions(+), 22 deletions(-)
> rename Documentation/{ => core-api}/errseq.rst (92%)
Nice. Thanks.
Reviewed-by: Randy Dunlap
--
~Randy
--
To unsubscribe from this list: send the line "unsubscribe linux-doc" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
