Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1688929

Re: [PATCH] printk: modify console_unlock with printk-safe macros

From pierre kuo <vichy.kuo@gmail.com>
Newsgroups linux.kernel
Subject Re: [PATCH] printk: modify console_unlock with printk-safe macros
Date 2017-07-17 13:10 +0200
Message-ID <u4c4z-4fj-13@gated-at.bofh.it> (permalink)
References <u3sEq-ke-21@gated-at.bofh.it> <u4avN-3bA-25@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


hi Sergey and Andy:
> On (07/15/17 18:36), Pierre Kuo wrote:
> [..]
>> diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
>> index fc47863..21557cc 100644
>> --- a/kernel/printk/printk.c
>> +++ b/kernel/printk/printk.c
>> @@ -2194,8 +2194,7 @@ void console_unlock(void)
>>               size_t ext_len = 0;
>>               size_t len;
>>
>> -             printk_safe_enter_irqsave(flags);
>> -             raw_spin_lock(&logbuf_lock);
>> +             logbuf_lock_irqsave(flags);
>>               if (seen_seq != log_next_seq) {
>>                       wake_klogd = true;
>>                       seen_seq = log_next_seq;
>> @@ -2267,8 +2266,7 @@ void console_unlock(void)
>>        */
>>       raw_spin_lock(&logbuf_lock);
>>       retry = console_seq != log_next_seq;
>> -     raw_spin_unlock(&logbuf_lock);
>> -     printk_safe_exit_irqrestore(flags);
>> +     logbuf_unlock_irqrestore(flags);
>>
>>       if (retry && console_trylock())
>>               goto again;
>
> I did it that particular way for a reason - console_unlock() does a
> bunch of tricks: unlocking logbuf in the middle of printing loop,
> breaking out of loop with local IRQs disabled, re-taking the logbuf
> after the loop still will local IRQs disabled, etc. etc. I didn't
> want to (and still don't) mix-in logbuf macros; we do things that
> macros don't cover anyway. sorry, I don't agree that the patch
> improves readability.
Got ur points and appreciate for your illustration. ^^
Thanks a lot,

Back to linux.kernel | Previous | NextPrevious in thread | Find similar | Unroll thread


Thread

[PATCH] printk: modify console_unlock with printk-safe macros Pierre Kuo <vichy.kuo@gmail.com> - 2017-07-15 12:40 +0200
  Re: [PATCH] printk: modify console_unlock with printk-safe macros Andy Shevchenko <andy.shevchenko@gmail.com> - 2017-07-15 14:40 +0200
  Re: [PATCH] printk: modify console_unlock with printk-safe macros Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> - 2017-07-17 11:30 +0200
    Re: [PATCH] printk: modify console_unlock with printk-safe macros pierre kuo <vichy.kuo@gmail.com> - 2017-07-17 13:10 +0200

csiph-web