Re: [PATCH] kfifo: add memory barrier in kfifo to prevent data loss

From: kbuild test robot
Date: Sun Dec 16 2018 - 10:46:56 EST


Hi Yulei,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v4.20-rc6 next-20181214]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url: https://github.com/0day-ci/linux/commits/yulei-kernel-gmail-com/kfifo-add-memory-barrier-in-kfifo-to-prevent-data-loss/20181211-204949
reproduce: make htmldocs

All warnings (new ones prefixed by >>):

WARNING: convert(1) not found, for SVG to PDF conversion install ImageMagick (https://www.imagemagick.org)
>> include/linux/kfifo.h:305: warning: Function parameter or member 'kfifo' not described in 'kfifo_read_index_in'
include/linux/kfifo.h:305: warning: Excess function parameter 'fifo' description in 'kfifo_read_index_in'
>> include/linux/kfifo.h:321: warning: Function parameter or member 'kfifo' not described in 'kfifo_write_index_in'
>> include/linux/kfifo.h:321: warning: Function parameter or member 'val' not described in 'kfifo_write_index_in'
include/linux/kfifo.h:321: warning: Excess function parameter 'fifo' description in 'kfifo_write_index_in'
>> include/linux/kfifo.h:337: warning: Function parameter or member 'kfifo' not described in 'kfifo_read_index_out'
include/linux/kfifo.h:337: warning: Excess function parameter 'fifo' description in 'kfifo_read_index_out'
>> include/linux/kfifo.h:353: warning: Function parameter or member 'kfifo' not described in 'kfifo_write_index_out'
>> include/linux/kfifo.h:353: warning: Function parameter or member 'val' not described in 'kfifo_write_index_out'
include/linux/kfifo.h:353: warning: Excess function parameter 'fifo' description in 'kfifo_write_index_out'
include/linux/rcutree.h:1: warning: no structured comments found
kernel/rcu/tree.c:684: warning: Excess function parameter 'irq' description in 'rcu_nmi_exit'
include/linux/srcu.h:175: warning: Function parameter or member 'p' not described in 'srcu_dereference_notrace'
include/linux/srcu.h:175: warning: Function parameter or member 'sp' not described in 'srcu_dereference_notrace'
include/linux/gfp.h:1: warning: no structured comments found
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:4439: warning: Function parameter or member 'wext.ibss' not described in 'wireless_dev'
include/net/cfg80211.h:4439: warning: Function parameter or member 'wext.connect' not described in 'wireless_dev'
include/net/cfg80211.h:4439: warning: Function parameter or member 'wext.keys' not described in 'wireless_dev'
include/net/cfg80211.h:4439: warning: Function parameter or member 'wext.ie' not described in 'wireless_dev'
include/net/cfg80211.h:4439: warning: Function parameter or member 'wext.ie_len' not described in 'wireless_dev'
include/net/cfg80211.h:4439: warning: Function parameter or member 'wext.bssid' not described in 'wireless_dev'
include/net/cfg80211.h:4439: warning: Function parameter or member 'wext.ssid' not described in 'wireless_dev'
include/net/cfg80211.h:4439: warning: Function parameter or member 'wext.default_key' not described in 'wireless_dev'
include/net/cfg80211.h:4439: warning: Function parameter or member 'wext.default_mgmt_key' not described in 'wireless_dev'
include/net/cfg80211.h:4439: warning: Function parameter or member 'wext.prev_bssid_valid' not described in 'wireless_dev'
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '
include/net/cfg80211.h:2838: warning: cannot understand function prototype: 'struct cfg80211_ftm_responder_stats '

vim +305 include/linux/kfifo.h

> 305
306 /**
307 * kfifo_write_index_in - updates the in index of the fifo
308 * @fifo: address of the kfifo to be used
309 *
310 * add memory write barrier to make sure the data entry is
311 * updated before increase the fifo->in
312 */
313 #define kfifo_write_index_in(kfifo, val) \
314 ({ \
315 typeof((kfifo) + 1) __tmp = (kfifo); \
316 struct __kfifo *__kfifo = __tmp; \
317 unsigned int __val = (val); \
318 smp_wmb(); \
319 WRITE_ONCE(__kfifo->in, __val); \
320 })
> 321
322 /**
323 * kfifo_read_index_out - returns the out index of the fifo
324 * @fifo: address of the kfifo to be used
325 *
326 * add memory barrier to make sure the fifo->out index is
327 * fetched before read data from the fifo, which is paired
328 * with the memory barrier in kfifo_write_index_out
329 */
330 #define kfifo_read_index_out(kfifo) \
331 ({ \
332 typeof((kfifo) + 1) __tmp = (kfifo); \
333 struct __kfifo *__kfifo = __tmp; \
334 unsigned int __val = smp_load_acquire(&__kfifo->out); \
335 __val; \
336 })
> 337
338 /**
339 * kfifo_write_index_out - updates the out index of the fifo
340 * @fifo: address of the kfifo to be used
341 *
342 * add memory barrier to make sure reading out the entry before
343 * update the fifo->out index to avoid overwitten the entry by
344 * the producer
345 */
346 #define kfifo_write_index_out(kfifo, val) \
347 ({ \
348 typeof((kfifo) + 1) __tmp = (kfifo); \
349 struct __kfifo *__kfifo = __tmp; \
350 unsigned int __val = (val); \
351 smp_store_release(&__kfifo->out, __val); \
352 })
> 353

---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation

Attachment: .config.gz
Description: application/gzip