Commit Graph

16 Commits

Author SHA1 Message Date
Wei Wang
94960256ae bitmap: bitmap_count_one_with_offset
Count the number of 1s in a bitmap starting from an offset.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1544516693-5395-3-git-send-email-wei.w.wang@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-03-06 10:49:17 +00:00
Wei Wang
e7c91368d2 bitmap: fix bitmap_count_one
BITMAP_LAST_WORD_MASK(nbits) returns 0xffffffff when "nbits=0", which
makes bitmap_count_one fail to handle the "nbits=0" case. It appears to be
preferred to remain BITMAP_LAST_WORD_MASK identical to the kernel
implementation that it is ported from.

So this patch fixes bitmap_count_one to handle the nbits=0 case.

Inital Discussion Link:
https://www.mail-archive.com/qemu-devel@nongnu.org/msg554316.html
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Peter Xu <peterx@redhat.com>
Message-Id: <1544516693-5395-2-git-send-email-wei.w.wang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-03-06 10:49:17 +00:00
Peter Xu
d7788151a0 bitmap: provide to_le/from_le helpers
Provide helpers to convert bitmaps to little endian format. It can be
used when we want to send one bitmap via network to some other hosts.

One thing to mention is that, these helpers only solve the problem of
endianess, but it does not solve the problem of different word size on
machines (the bitmaps managing same count of bits may contains different
size when malloced). So we need to take care of the size alignment issue
on the callers for now.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-09-22 14:11:25 +02:00
Peter Xu
fc7deeea26 bitmap: introduce bitmap_count_one()
Count how many bits set in the bitmap.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-09-22 14:11:24 +02:00
Gerd Hoffmann
d6eb141392 bitmap: add bitmap_copy_and_clear_atomic
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20170421091632.30900-2-kraxel@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2017-04-24 10:12:28 +02:00
Wei Yang
cb57fb3705 bitmap: refine and move BITMAP_{FIRST/LAST}_WORD_MASK
According to linux kernel commit <89c1e79eb30> ("linux/bitmap.h: improve
BITMAP_{LAST,FIRST}_WORD_MASK"), these two macro could be improved.

This patch takes this change and also move them all in header file.

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-10-08 11:25:29 +03:00
Ladi Prosek
d4b84d564e Remove unused function declarations
Unused function declarations were found using a simple gcc plugin and
manually verified by grepping the sources.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-09-15 15:32:22 +03:00
Peter Maydell
030c98aff1 all: Remove unnecessary glib.h includes
Remove glib.h includes, as it is provided by osdep.h.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-06-07 18:19:24 +03:00
Peter Maydell
90ce6e2644 include: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

NB: If this commit breaks compilation for your out-of-tree
patchseries or fork, then you need to make sure you add
#include "qemu/osdep.h" to any new .c files that you have.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-23 12:43:05 +00:00
Stefan Hajnoczi
36546e5b80 bitmap: add atomic test and clear
The new bitmap_test_and_clear_atomic() function clears a range and
returns whether or not the bits were set.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1417519399-3166-3-git-send-email-stefanha@redhat.com>
[Test before xchg; then a full barrier is needed at the end just like
 in the previous patch.  The barrier can be avoided if we did at least
 one xchg.  - Paolo]
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:10:00 +02:00
Stefan Hajnoczi
9f02cfc84b bitmap: add atomic set functions
Use atomic_or() for atomic bitmaps where several threads may set bits at
the same time.  This avoids the race condition between threads loading
an element, bitwise ORing, and then storing the element.

When setting all bits in a word we can avoid atomic ops and instead just
use an smp_mb() at the end.

Most bitmap users don't need atomicity so introduce new functions.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1417519399-3166-2-git-send-email-stefanha@redhat.com>
[Avoid barrier in the single word case, use full barrier instead of write.
 - Paolo]
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:10:00 +02:00
Eduardo Habkost
d6aaddfe97 bitmap.h: Don't include qemu-common.h
This will avoid unexpected circular header dependencies in the future.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-11-02 10:04:34 +03:00
Peter Lieven
be4d57c1ea util: introduce bitmap_try_new
regular bitmap_new simply aborts if the memory allocation fails.
bitmap_try_new returns NULL on failure and allows for proper
error handling.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-30 13:30:51 +02:00
Juan Quintela
164590a60f bitmap: Add bitmap_zero_extend operation
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Orit Wasserman <owasserm@redhat.com>
2014-01-13 14:04:54 +01:00
Juan Quintela
9c22687ea8 bitmap: use long as index
Move index and size fields from int to long.  We need that for
migration.  long is 64 bits on sane architectures, and 32bits should
be enough on all the 32bits architectures.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Orit Wasserman <owasserm@redhat.com>
2014-01-13 14:04:53 +01:00
Paolo Bonzini
1de7afc984 misc: move include files to include/qemu/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:32:39 +01:00