From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:55874) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RiNCZ-0000l7-Th for qemu-devel@nongnu.org; Wed, 04 Jan 2012 04:32:08 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RiNCY-00077c-Nz for qemu-devel@nongnu.org; Wed, 04 Jan 2012 04:32:07 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57040) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RiNCY-00077U-Ga for qemu-devel@nongnu.org; Wed, 04 Jan 2012 04:32:06 -0500 Message-ID: <4F041C69.3030700@redhat.com> Date: Wed, 04 Jan 2012 11:31:21 +0200 From: Orit Wasserman MIME-Version: 1.0 References: <1325604879-15862-1-git-send-email-owasserm@redhat.com> <1325604879-15862-3-git-send-email-owasserm@redhat.com> <4F035D8E.2050103@redhat.com> In-Reply-To: <4F035D8E.2050103@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v5 2/9] Add rle_encode and rle_decode functions Implement Run Length Encoding compression List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: blauwirbel@gmail.com, stefanha@gmail.com, qemu-devel@nongnu.org, quintela@redhat.com On 01/03/2012 09:57 PM, Anthony Liguori wrote: > On 01/03/2012 09:34 AM, Orit Wasserman wrote: >> Signed-off-by: Orit Wasserman >> --- >> arch_init.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ >> 1 files changed, 58 insertions(+), 0 deletions(-) >> >> diff --git a/arch_init.c b/arch_init.c >> index fdda277..426b34d 100644 >> --- a/arch_init.c >> +++ b/arch_init.c >> @@ -139,6 +139,9 @@ typedef struct XBRLEHeader { >> uint32_t xh_cksum; >> } XBRLEHeader; >> >> +static int rle_encode(uint8_t *src, int slen, uint8_t *dst, int dlen); >> +static int rle_decode(uint8_t *src, int slen, uint8_t *dst, int dlen); >> + >> /***********************************************************/ >> /* XBRLE page cache implementation */ >> static CacheItem *cache_item_get(unsigned long pos, int item) >> @@ -277,6 +280,61 @@ static void cache_insert(unsigned long addr, uint8_t *pdata) >> it->it_addr = addr; >> } >> >> +/* XBRLE (Xor Based Run-Length Encoding) */ >> +static int rle_encode(uint8_t *src, int slen, uint8_t *dst, int dlen) >> +{ >> + int d = 0, ch_run = 0, i; >> + uint8_t prev = 0, ch = 0; >> + >> + for (i = 0; i<= slen; i++) { >> + if (i != slen) { >> + ch = src[i]; >> + } >> + >> + if (!i || (i != slen&& ch == prev&& ch_run< 255)) { >> + ch_run++; >> + } else { >> + if (d+2> dlen) { >> + return -1; >> + } >> + *dst++ = ch_run; >> + *dst++ = prev; >> + d += 2; >> + ch_run = 1; >> + } >> + >> + prev = ch; >> + } >> + return d; >> +} >> + >> +static int rle_decode(uint8_t *src, int slen, uint8_t *dst, int dlen) >> +{ >> + int d = 0, s; >> + >> + for (s = 0; s< slen-1; s += 2) { >> + uint8_t ch_run = src[s]; >> + uint8_t ch = src[s+1]; >> + while (ch_run--) { >> + if (d == dlen) { >> + return -1; >> + } >> + dst[d] = ch; >> + d++; >> + } >> + } >> + return d; >> +} >> + >> +static void xor_encode(uint8_t *dst, uint8_t *src1, uint8_t *src2) >> +{ >> + int i; >> + >> + for (i = 0; i< TARGET_PAGE_SIZE; i++) { >> + dst[i] = src1[i] ^ src2[i]; >> + } >> +} >> + > > I don't think any of these need to be in arch_init.c. It would be nicer to make a xbzrle.c file for this stuff. > I will fix it. > Regards, > > Anthony Liguori > >> static int is_dup_page(uint8_t *page, uint8_t ch) >> { >> uint32_t val = ch<< 24 | ch<< 16 | ch<< 8 | ch; > >