From: Wei Yang <richard.weiyang@gmail.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: quintela@redhat.com, corentincj@iksaif.net, pl@kamp.de,
qemu-devel@nongnu.org, peterx@redhat.com,
Wei Yang <richard.weiyang@gmail.com>,
Wei Yang <richardw.yang@linux.intel.com>,
kraxel@redhat.com
Subject: Re: [Qemu-devel] [PATCH v3 1/2] bitmap: get last word mask from nr directly
Date: Mon, 22 Jul 2019 00:29:45 +0000 [thread overview]
Message-ID: <20190722002945.iur4iu4nxployiss@master> (raw)
In-Reply-To: <796ed0ca-ecd7-9f18-71fa-59b94c403cbc@redhat.com>
On Sun, Jul 21, 2019 at 07:27:14PM +0200, Paolo Bonzini wrote:
>On 21/07/19 02:33, Wei Yang wrote:
>> On Thu, Jul 18, 2019 at 09:04:55AM +0800, Wei Yang wrote:
>>> The value left in nr is the number of bits for the last word, which
>>> could be calculate the last word mask directly.
>>>
>>> Remove the unnecessary size.
>>>
>>
>> May I ask why Patch 2 is picked up, but this one is not?
>
>Tests are always good to have, this cleanup will wait for 4.2 but it's
>in the queue.
>
Thanks :-)
>Paolo
>
>>> Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
>>>
>>> ---
>>> v2: refine bitmap_set_atomic too, suggested from Peter
>>> ---
>>> util/bitmap.c | 9 +++------
>>> 1 file changed, 3 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/util/bitmap.c b/util/bitmap.c
>>> index 1753ff7f5b..5b15249796 100644
>>> --- a/util/bitmap.c
>>> +++ b/util/bitmap.c
>>> @@ -160,7 +160,6 @@ int slow_bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
>>> void bitmap_set(unsigned long *map, long start, long nr)
>>> {
>>> unsigned long *p = map + BIT_WORD(start);
>>> - const long size = start + nr;
>>> int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
>>> unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
>>>
>>> @@ -174,7 +173,7 @@ void bitmap_set(unsigned long *map, long start, long nr)
>>> p++;
>>> }
>>> if (nr) {
>>> - mask_to_set &= BITMAP_LAST_WORD_MASK(size);
>>> + mask_to_set &= BITMAP_LAST_WORD_MASK(nr);
>>> *p |= mask_to_set;
>>> }
>>> }
>>> @@ -182,7 +181,6 @@ void bitmap_set(unsigned long *map, long start, long nr)
>>> void bitmap_set_atomic(unsigned long *map, long start, long nr)
>>> {
>>> unsigned long *p = map + BIT_WORD(start);
>>> - const long size = start + nr;
>>> int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
>>> unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
>>>
>>> @@ -208,7 +206,7 @@ void bitmap_set_atomic(unsigned long *map, long start, long nr)
>>>
>>> /* Last word */
>>> if (nr) {
>>> - mask_to_set &= BITMAP_LAST_WORD_MASK(size);
>>> + mask_to_set &= BITMAP_LAST_WORD_MASK(nr);
>>> atomic_or(p, mask_to_set);
>>> } else {
>>> /* If we avoided the full barrier in atomic_or(), issue a
>>> @@ -221,7 +219,6 @@ void bitmap_set_atomic(unsigned long *map, long start, long nr)
>>> void bitmap_clear(unsigned long *map, long start, long nr)
>>> {
>>> unsigned long *p = map + BIT_WORD(start);
>>> - const long size = start + nr;
>>> int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
>>> unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
>>>
>>> @@ -235,7 +232,7 @@ void bitmap_clear(unsigned long *map, long start, long nr)
>>> p++;
>>> }
>>> if (nr) {
>>> - mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
>>> + mask_to_clear &= BITMAP_LAST_WORD_MASK(nr);
>>> *p &= ~mask_to_clear;
>>> }
>>> }
>>> --
>>> 2.17.1
>>>
>>
--
Wei Yang
Help you, Help me
next prev parent reply other threads:[~2019-07-22 0:30 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-18 1:04 [Qemu-devel] [PATCH v3 0/2] bitmap: refine bitmap_set Wei Yang
2019-07-18 1:04 ` [Qemu-devel] [PATCH v3 1/2] bitmap: get last word mask from nr directly Wei Yang
2019-07-21 0:33 ` Wei Yang
2019-07-21 17:27 ` Paolo Bonzini
2019-07-22 0:29 ` Wei Yang [this message]
2019-08-12 16:18 ` Paolo Bonzini
2019-08-13 13:32 ` Wei Yang
2019-07-18 1:04 ` [Qemu-devel] [PATCH v3 2/2] test-bitmap: add test for bitmap_set Wei Yang
2019-07-18 1:45 ` [Qemu-devel] [PATCH v3 0/2] bitmap: refine bitmap_set Peter Xu
2019-07-18 9:53 ` Paolo Bonzini
2019-07-18 11:40 ` no-reply
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190722002945.iur4iu4nxployiss@master \
--to=richard.weiyang@gmail.com \
--cc=corentincj@iksaif.net \
--cc=kraxel@redhat.com \
--cc=pbonzini@redhat.com \
--cc=peterx@redhat.com \
--cc=pl@kamp.de \
--cc=qemu-devel@nongnu.org \
--cc=quintela@redhat.com \
--cc=richardw.yang@linux.intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).