[PATCH v1] Improve the performance of --num-threads -d 31

Minoru Usui min-usui at ti.jp.nec.com
Mon Feb 22 18:16:28 PST 2016


Hello Zhou

I'm sorry for late reply, too.

> -----Original Message-----
> From: "Zhou, Wenjian/周文剑" [mailto:zhouwj-fnst at cn.fujitsu.com]
> Sent: Monday, February 15, 2016 11:15 AM
> To: Usui Minoru(碓井 成) <min-usui at ti.jp.nec.com>; kexec at lists.infradead.org
> Subject: Re: [PATCH v1] Improve the performance of --num-threads -d 31
> 
> Hello Usui,
> 
> Thanks very much for your comments.
> And sorry for the late reply.
> 
> See below.
> 
> On 02/08/2016 01:00 PM, Minoru Usui wrote:
> > Hello,
> >
> >> -----Original Message-----
> >> From: kexec [mailto:kexec-bounces at lists.infradead.org] On Behalf Of Minoru Usui
> >> Sent: Thursday, February 04, 2016 8:52 AM
> >> To: Zhou Wenjian <zhouwj-fnst at cn.fujitsu.com>; kexec at lists.infradead.org
> >> Subject: Re: [PATCH v1] Improve the performance of --num-threads -d 31
> >>
> >> Hi, Zhou
> >>
> >> I have some comments.
> >> I'm sorry if I have misunderstood your code.
> >>
> >>> -----Original Message-----
> >>> From: kexec [mailto:kexec-bounces at lists.infradead.org] On Behalf Of Zhou Wenjian
> >>> Sent: Monday, February 01, 2016 3:22 PM
> >>> To: kexec at lists.infradead.org
> >>> Subject: [PATCH v1] Improve the performance of --num-threads -d 31
> >>>
> >>> v1:
> >>>          1. change page_flag.ready's value to enum
> >>>          2. change the patch description
> >>>          3. cleanup some codes
> >>> 	4. fix a bug in cyclic mode
> >>>
> >>> multi-threads implementation will introduce extra cost when handling
> >>> each page. The origin implementation will also do the extra work for
> >>> filtered pages. So there is a big performance degradation in
> >>> --num-threads -d 31.
> >>> The new implementation won't do the extra work for filtered pages any
> >>> more. So the performance of -d 31 is close to that of serial processing.
> >>>
> >>> The new implementation is just like the following:
> >>>          * The basic idea is producer producing page and consumer writing page.
> >>>          * Each producer have a page_flag_buf list which is used for storing
> >>>            page's description.
> >>>          * The size of page_flag_buf is little so it won't take too much memory.
> >>>          * And all producers will share a page_data_buf array which is
> >>>            used for storing page's compressed data.
> >>>          * The main thread is the consumer. It will find the next pfn and write
> >>>            it into file.
> >>>          * The next pfn is smallest pfn in all page_flag_buf.
> >>>
> >>> Signed-off-by: Zhou Wenjian <zhouwj-fnst at cn.fujitsu.com>
> >>> ---
> >>>   makedumpfile.c | 258 ++++++++++++++++++++++++++++++++++++++-------------------
> >>>   makedumpfile.h |  31 ++++---
> >>>   2 files changed, 193 insertions(+), 96 deletions(-)
> >>>
> >>> diff --git a/makedumpfile.c b/makedumpfile.c
> >>> index fa0b779..0ecd065 100644
> >>> --- a/makedumpfile.c
> >>> +++ b/makedumpfile.c
> >>> @@ -3483,7 +3483,8 @@ initial_for_parallel()
> >>>   	unsigned long page_data_buf_size;
> >>>   	unsigned long limit_size;
> >>>   	int page_data_num;
> >>> -	int i;
> >>> +	struct page_flag *current;
> >>> +	int i, j;
> >>>
> >>>   	len_buf_out = calculate_len_buf_out(info->page_size);
> >>>
> >>> @@ -3562,8 +3563,10 @@ initial_for_parallel()
> >>>   		      - MAP_REGION * info->num_threads) * 0.6;
> >>>
> >>>   	page_data_num = limit_size / page_data_buf_size;
> >>> +	info->num_buffers = 3 * info->num_threads;
> >>>
> >>> -	info->num_buffers = MIN(NUM_BUFFERS, page_data_num);
> >>> +	info->num_buffers = MAX(info->num_buffers, NUM_BUFFERS);
> >>> +	info->num_buffers = MIN(info->num_buffers, page_data_num);
> >>>
> >>>   	DEBUG_MSG("Number of struct page_data for produce/consume: %d\n",
> >>>   			info->num_buffers);
> >>> @@ -3588,6 +3591,36 @@ initial_for_parallel()
> >>>   	}
> >>>
> >>>   	/*
> >>> +	 * initial page_flag for each thread
> >>> +	 */
> >>> +	if ((info->page_flag_buf = malloc(sizeof(void *) * info->num_threads))
> >>> +	    == NULL) {
> >>> +		MSG("Can't allocate memory for page_flag_buf. %s\n",
> >>> +				strerror(errno));
> >>> +		return FALSE;
> >>> +	}
> >>> +	memset(info->page_flag_buf, 0, sizeof(void *) * info->num_threads);
> >>> +
> >>> +	for (i = 0; i < info->num_threads; i++) {
> >>> +		if ((info->page_flag_buf[i] = malloc(sizeof(struct page_flag))) == NULL) {
> >>
> >> Fist element of struct page_flag in circular list is allocated by malloc(),
> >> but other elements are allocated by calloc().(see below)
> >> I think both elements should be allocated by calloc().
> >>
> 
> Yes, you are right.
> I have made a mistake.
> 
> >>> +			MSG("Can't allocate memory for page_flag_buf. %s\n",
> >>> +				strerror(errno));
> >>> +			return FALSE;
> >>> +		}
> >>> +		current = info->page_flag_buf[i];
> >>> +
> >>> +		for (j = 1; j < NUM_BUFFERS; j++) {
> >>> +			if ((current->next = calloc(0, sizeof(struct page_flag))) == NULL) {
> >>> +				MSG("Can't allocate memory for data of page_data_buf. %s\n",
> >>> +					strerror(errno));
> >>> +				return FALSE;
> >>> +			}
> >>
> >>
> >> First argument of calloc() should be 1, not 0.
> >> And there is typo in error message.
> >> Allocated element is not page_data_buf.
> >>
> 
> I agree.
> 
> >>> +			current = current->next;
> >>> +		}
> >>> +		current->next = info->page_flag_buf[i];
> >>> +	}
> >>> +
> >>> +	/*
> >>>   	 * initial fd_memory for threads
> >>>   	 */
> >>>   	for (i = 0; i < info->num_threads; i++) {
> >>> @@ -3612,7 +3645,8 @@ initial_for_parallel()
> >>>   void
> >>>   free_for_parallel()
> >>>   {
> >>> -	int i;
> >>> +	int i, j;
> >>> +	struct page_flag *current;
> >>>
> >>>   	if (info->threads != NULL) {
> >>>   		for (i = 0; i < info->num_threads; i++) {
> >>> @@ -3655,6 +3689,19 @@ free_for_parallel()
> >>>   		free(info->page_data_buf);
> >>>   	}
> >>>
> >>> +	if (info->page_flag_buf != NULL) {
> >>> +		for (i = 0; i < info->num_threads; i++) {
> >>> +			for (j = 0; j < NUM_BUFFERS; j++) {
> >>> +				if (info->page_flag_buf[i] != NULL) {
> >>> +					current = info->page_flag_buf[i];
> >>> +					info->page_flag_buf[i] = current->next;
> >>> +					free(current);
> >>> +				}
> >>> +			}
> >>> +		}
> >>> +		free(info->page_flag_buf);
> >>> +	}
> >>> +
> >>>   	if (info->parallel_info == NULL)
> >>>   		return;
> >>>
> >>> @@ -7076,10 +7123,10 @@ kdump_thread_function_cyclic(void *arg) {
> >>>   	void *retval = PTHREAD_FAIL;
> >>>   	struct thread_args *kdump_thread_args = (struct thread_args *)arg;
> >>>   	struct page_data *page_data_buf = kdump_thread_args->page_data_buf;
> >>> +	struct page_flag *page_flag_buf = kdump_thread_args->page_flag_buf;
> >>>   	struct cycle *cycle = kdump_thread_args->cycle;
> >>> -	int page_data_num = kdump_thread_args->page_data_num;
> >>>   	mdf_pfn_t pfn;
> >>> -	int index;
> >>> +	int index = kdump_thread_args->thread_num;
> >>>   	int buf_ready;
> >>>   	int dumpable;
> >>>   	int fd_memory = 0;
> >>> @@ -7125,47 +7172,47 @@ kdump_thread_function_cyclic(void *arg) {
> >>>   						kdump_thread_args->thread_num);
> >>>   	}
> >>>
> >>> -	while (1) {
> >>> -		/* get next pfn */
> >>> -		pthread_mutex_lock(&info->current_pfn_mutex);
> >>> -		pfn = info->current_pfn;
> >>> -		info->current_pfn++;
> >>> -		pthread_mutex_unlock(&info->current_pfn_mutex);
> >>> +	/*
> >>> +	 * filtered page won't take anything
> >>> +	 * unfiltered zero page will only take a page_flag_buf
> >>> +	 * unfiltered non-zero page will take a page_flag_buf and a page_data_buf
> >>> +	 */
> >>> +	while (page_flag_buf->pfn < kdump_thread_args->end_pfn) {
> >>
> >> At first, page_flag_buf->pfn is not initialized.
> >> I think this block should be replaced with the following code.
> >>
> >> ===
> >>    do {
> >>      :
> >>    } while(page_flag_buf->pfn < kdump_thread_args->end_pfn)
> >> ===
> >
> > I'm sorry, above suggestion is meaningless in terms of page_flag_buf->pfn is uninitialized.
> > It should be replaced like following.
> >
> > ===
> >    while (1) {
> >      :
> >      while (buf_ready == FALSE) {
> >         :
> >        if (pfn >= kdump_thread_args->end_pfn) {
> >           :
> >          goto finish;
> >        }
> >        :
> >      }
> >      :
> >    }
> > finish:
> > ===
> >
> 
> page_flag_buf is allocated by calloc().
> The page_flag_buf->pfn's value is 0.
> So I think it is not necessary to modify the code.
> 
> > Thanks,
> > Minoru Usui
> >
> >
> >>> +		buf_ready = FALSE;
> >>>
> >>> -		if (pfn >= kdump_thread_args->end_pfn)
> >>> -			break;
> >>> +		while (page_data_buf[index].used != 0 ||
> >>> +				pthread_mutex_trylock(&page_data_buf[index].mutex) != 0)
> >>> +			index = (index + 1) % info->num_buffers;
> >>>
> >>> -		index = -1;
> >>> -		buf_ready = FALSE;
> >>> +		page_data_buf[index].used = 1;
> >>
> >> "1" is a magic number.
> >> It should be changed TRUE or FALSE.
> >>
> 
> I see.
> 
> >>>   		while (buf_ready == FALSE) {
> >>>   			pthread_testcancel();
> >>> -
> >>> -			index = pfn % page_data_num;
> >>> -
> >>> -			if (pfn - info->consumed_pfn > info->num_buffers)
> >>> +			if (page_flag_buf->ready == FLAG_READY)
> >>>   				continue;
> >>
> >> At first, page_flag_buf->ready is uninitialized, too.
> >> Should it be initialized in head part of this function, even if FLAG_UNUSED is defined 0?
> >>
> >>
> 
> The same topic as the page_flag_buf is allocated by calloc().
> 
> >>>
> >>> -			if (page_data_buf[index].ready != 0)
> >>> -				continue;
> >>> -
> >>> -			pthread_mutex_lock(&page_data_buf[index].mutex);
> >>> +			/* get next pfn */
> >>> +			pthread_mutex_lock(&info->current_pfn_mutex);
> >>> +			pfn = info->current_pfn;
> >>> +			info->current_pfn++;
> >>> +			page_flag_buf->ready = FLAG_FILLING;
> >>> +			pthread_mutex_unlock(&info->current_pfn_mutex);
> >>>
> >>> -			if (page_data_buf[index].ready != 0)
> >>> -				goto unlock;
> >>> +			page_flag_buf->pfn = pfn;
> >>
> >> It set FLAG_FILLING to page_flag_buf->ready before setting pfn to page_flag_buf->pfn.
> >> But consumer gets page_flag_buf->pfn after checking page_flag_buf->ready != FLAG_UNUSED
> >> in getting minimum pfn of each thread block.
> >> Should it set page_flag_buf->pfn first?
> >>
> 
> Have you noticed the following code in the consumer?
> <cut>
>                          if (current_pfn == info->page_flag_buf[consuming]->pfn)
>                                  break;
> <cut>

No, I pointed following code.
This part accesses info->page_flag_buf[i]->ready, then it accesses info->page_flag_buf[i]->pfn immediately.
So, temp_pfn may be wrong pfn at this moment.

---
                        for (i = 0; i < info->num_threads; i++) {
                                if (info->page_flag_buf[i]->ready == FLAG_UNUSED)
                                        continue;
                                temp_pfn = info->page_flag_buf[i]->pfn;
---

> The consumer will check if the pfn is changed after the page_flag_buf->ready turns to be FLAG_READY.
> So it's not important whether setting page_flag_buf->pfn first or not.

As you said, consumer checks pfn which is changed.
So it works well.

> In the other hand, even setting page_flag_buf->pfn first, if the pfn is not dumpable, the producer
> will also reset the page_flag_buf->pfn.

Thank you for your explanation.
I didn't notice that pfn can be undumpable.

> >>>
> >>> -			buf_ready = TRUE;
> >>> -
> >>> -			page_data_buf[index].pfn = pfn;
> >>> -			page_data_buf[index].ready = 1;
> >>> +			if (pfn >= kdump_thread_args->end_pfn) {
> >>> +				page_data_buf[index].used = 0;
> >>> +				page_flag_buf->ready = FLAG_READY;
> >>> +				info->current_pfn--;
> >>> +				break;
> >>> +			}
> >>
> >> This block decrements info->current_pfn without info->current_pfn_mutex.
> >> I think this block should be moved into previous pthread_mutex_lock(info->current_pfn_mutex) block, so it can remove.
> >>
> 
> Why do you think it should have current_pfn_mutex?
> 
> If pfn >= kdump_thread_args->end_pfn, info->current_pfn will always larger than
> kdump_thread_args->end_pfn. info->current_pfn-- won't affect anything.
> 
> The decrement operation is for cyclic mode.
> 
> >>>
> >>>   			dumpable = is_dumpable(
> >>>   				info->fd_bitmap ? &bitmap_parallel : info->bitmap2,
> >>>   				pfn,
> >>>   				cycle);
> >>> -			page_data_buf[index].dumpable = dumpable;
> >>>   			if (!dumpable)
> >>> -				goto unlock;
> >>> +				continue;
> >>>
> >>>   			if (!read_pfn_parallel(fd_memory, pfn, buf,
> >>>   					       &bitmap_memory_parallel,
> >>> @@ -7178,11 +7225,11 @@ kdump_thread_function_cyclic(void *arg) {
> >>>
> >>>   			if ((info->dump_level & DL_EXCLUDE_ZERO)
> >>>   			    && is_zero_page(buf, info->page_size)) {
> >>> -				page_data_buf[index].zero = TRUE;
> >>> -				goto unlock;
> >>> +				page_flag_buf->zero = TRUE;
> >>> +				goto next;
> >>>   			}
> >>
> >> First, this code gets page_data_buf, then it gets page_flag_buf.
> >> However, if processed pfn is zero page,
> >> it processes next pfn while keeping page_data_buf.
> >>
> >> I think it should get page_flag_buf, then get page_data_buf
> >> in order to shorten the holding period of the page_data_buf[index].mutex.
> >>
> 
> Do you mean the following logic?
> 1. get the page_flag_buf first
> 2. if the pfn is not zero page, then get the page_data_buf.

Yes.

> Think about the following case.
> A producer get the page_flag_buf, and the pfn is not zero page.
> It wants to get a page_data_buf, but there is no more page_data_buf.
> Then ...

It's not a problem.
In not zero page case, this logic needs both page_flag_buf and page_data_buf,
so waiting buffer is obvious when it isn't able to get page_flag_buf or page_data_buf.
 
> Since there are several page_data_bufs, it's not a problem that each producer
> will always hold a page_data_buf.

It depends on the speed of consumer and producer.
It's not possible to predict it.

In zero page case, I think each producer executes more parallel theoretically
if page_data_buf doesn't get.

Thanks,
Minoru Usui

> 
> Thanks again for your comments.
> And I will post the next version later.
> 
> --
> Thanks
> Zhou
> 
> >> Thanks,
> >> Minoru Usui
> >>
> >>>
> >>> -			page_data_buf[index].zero = FALSE;
> >>> +			page_flag_buf->zero = FALSE;
> >>>
> >>>   			/*
> >>>   			 * Compress the page data.
> >>> @@ -7232,12 +7279,16 @@ kdump_thread_function_cyclic(void *arg) {
> >>>   				page_data_buf[index].size  = info->page_size;
> >>>   				memcpy(page_data_buf[index].buf, buf, info->page_size);
> >>>   			}
> >>> -unlock:
> >>> -			pthread_mutex_unlock(&page_data_buf[index].mutex);
> >>> +			page_flag_buf->index = index;
> >>> +			buf_ready = TRUE;
> >>> +next:
> >>> +			page_flag_buf->ready = FLAG_READY;
> >>> +			page_flag_buf = page_flag_buf->next;
> >>>
> >>>   		}
> >>> -	}
> >>>
> >>> +		pthread_mutex_unlock(&page_data_buf[index].mutex);
> >>> +	}
> >>>   	retval = NULL;
> >>>
> >>>   fail:
> >>> @@ -7265,14 +7316,15 @@ write_kdump_pages_parallel_cyclic(struct cache_data *cd_header,
> >>>   	struct page_desc pd;
> >>>   	struct timeval tv_start;
> >>>   	struct timeval last, new;
> >>> -	unsigned long long consuming_pfn;
> >>>   	pthread_t **threads = NULL;
> >>>   	struct thread_args *kdump_thread_args = NULL;
> >>>   	void *thread_result;
> >>> -	int page_data_num;
> >>> +	int page_buf_num;
> >>>   	struct page_data *page_data_buf = NULL;
> >>>   	int i;
> >>>   	int index;
> >>> +	int end_count, consuming, check_count;
> >>> +	mdf_pfn_t current_pfn, temp_pfn;
> >>>
> >>>   	if (info->flag_elf_dumpfile)
> >>>   		return FALSE;
> >>> @@ -7319,16 +7371,11 @@ write_kdump_pages_parallel_cyclic(struct cache_data *cd_header,
> >>>   	threads = info->threads;
> >>>   	kdump_thread_args = info->kdump_thread_args;
> >>>
> >>> -	page_data_num = info->num_buffers;
> >>> +	page_buf_num = info->num_buffers;
> >>>   	page_data_buf = info->page_data_buf;
> >>>
> >>> -	for (i = 0; i < page_data_num; i++) {
> >>> -		/*
> >>> -		 * producer will use pfn in page_data_buf to decide the
> >>> -		 * consumed pfn
> >>> -		 */
> >>> -		page_data_buf[i].pfn = start_pfn - 1;
> >>> -		page_data_buf[i].ready = 0;
> >>> +	for (i = 0; i < page_buf_num; i++) {
> >>> +		page_data_buf[i].used = 0;
> >>>   		res = pthread_mutex_init(&page_data_buf[i].mutex, NULL);
> >>>   		if (res != 0) {
> >>>   			ERRMSG("Can't initialize mutex of page_data_buf. %s\n",
> >>> @@ -7342,8 +7389,9 @@ write_kdump_pages_parallel_cyclic(struct cache_data *cd_header,
> >>>   		kdump_thread_args[i].len_buf_out = len_buf_out;
> >>>   		kdump_thread_args[i].start_pfn = start_pfn;
> >>>   		kdump_thread_args[i].end_pfn = end_pfn;
> >>> -		kdump_thread_args[i].page_data_num = page_data_num;
> >>> +		kdump_thread_args[i].page_buf_num = page_buf_num;
> >>>   		kdump_thread_args[i].page_data_buf = page_data_buf;
> >>> +		kdump_thread_args[i].page_flag_buf = info->page_flag_buf[i];
> >>>   		kdump_thread_args[i].cycle = cycle;
> >>>
> >>>   		res = pthread_create(threads[i], NULL,
> >>> @@ -7356,55 +7404,94 @@ write_kdump_pages_parallel_cyclic(struct cache_data *cd_header,
> >>>   		}
> >>>   	}
> >>>
> >>> -	consuming_pfn = start_pfn;
> >>> -	index = -1;
> >>> +	while (1) {
> >>> +		consuming = 0;
> >>> +		check_count = 0;
> >>> +		end_count = 0;
> >>>
> >>> -	gettimeofday(&last, NULL);
> >>> +		/*
> >>> +		 * The basic idea is producer producing page and consumer writing page.
> >>> +		 * Each producer have a page_flag_buf list which is used for storing page's description.
> >>> +		 * The size of page_flag_buf is little so it won't take too much memory.
> >>> +		 * And all producers will share a page_data_buf array which is used for storing page's compressed data.
> >>> +		 * The main thread is the consumer. It will find the next pfn and write it into file.
> >>> +		 * The next pfn is smallest pfn in all page_flag_buf.
> >>> +		 */
> >>> +		while (1) {
> >>> +			current_pfn = end_pfn;
> >>>
> >>> -	while (consuming_pfn < end_pfn) {
> >>> -		index = consuming_pfn % page_data_num;
> >>> +			/*
> >>> +			 * page_flag_buf is in circular linked list.
> >>> +			 * The array info->page_flag_buf[] records the current page_flag_buf in each thread's
> >>> +			 * page_flag_buf list.
> >>> +			 * consuming is used for recording in which thread the pfn is the smallest.
> >>> +			 * current_pfn is used for recording the value of pfn when checking the pfn.
> >>> +			 */
> >>> +			for (i = 0; i < info->num_threads; i++) {
> >>> +				if (info->page_flag_buf[i]->ready == FLAG_UNUSED)
> >>> +					continue;
> >>> +				temp_pfn = info->page_flag_buf[i]->pfn;
> >>>
> >>> -		gettimeofday(&new, NULL);
> >>> -		if (new.tv_sec - last.tv_sec > WAIT_TIME) {
> >>> -			ERRMSG("Can't get data of pfn %llx.\n", consuming_pfn);
> >>> -			goto out;
> >>> -		}
> >>> +				/*
> >>> +				 * count how many threads have reached the end.
> >>> +				 */
> >>> +				if (temp_pfn >= end_pfn) {
> >>> +					end_count++;
> >>> +					info->page_flag_buf[i]->ready = FLAG_UNUSED;
> >>> +					continue;
> >>> +				}
> >>>
> >>> -		/*
> >>> -		 * check pfn first without mutex locked to reduce the time
> >>> -		 * trying to lock the mutex
> >>> -		 */
> >>> -		if (page_data_buf[index].pfn != consuming_pfn)
> >>> -			continue;
> >>> +				if (current_pfn < temp_pfn)
> >>> +					continue;
> >>>
> >>> -		if (pthread_mutex_trylock(&page_data_buf[index].mutex) != 0)
> >>> -			continue;
> >>> +				check_count++;
> >>> +				consuming = i;
> >>> +				current_pfn = temp_pfn;
> >>> +			}
> >>> +
> >>> +			/*
> >>> +			 * If all the threads have reached the end, we will finish writing.
> >>> +			 */
> >>> +			if (end_count >= info->num_threads)
> >>> +				goto finish;
> >>> +
> >>> +			/*
> >>> +			 * Since it has the probabilty that there is no page_flag_buf being ready,
> >>> +			 * we should recheck if it happens.
> >>> +			 */
> >>> +			if (check_count == 0)
> >>> +				continue;
> >>> +
> >>> +			/*
> >>> +			 * When we check the pfn in page_flag_buf, it may be being produced.
> >>> +			 * So we should wait until it is ready to use. And if the pfn is
> >>> +			 * different from the value when we check, we should rechoose the buf.
> >>> +			 */
> >>> +			gettimeofday(&last, NULL);
> >>> +			while (info->page_flag_buf[consuming]->ready != FLAG_READY) {
> >>> +				gettimeofday(&new, NULL);
> >>> +				if (new.tv_sec - last.tv_sec > WAIT_TIME) {
> >>> +					ERRMSG("Can't get data of pfn.\n");
> >>> +					goto out;
> >>> +				}
> >>> +			}
> >>>
> >>> -		/* check whether the found one is ready to be consumed */
> >>> -		if (page_data_buf[index].pfn != consuming_pfn ||
> >>> -		    page_data_buf[index].ready != 1) {
> >>> -			goto unlock;
> >>> +			if (current_pfn == info->page_flag_buf[consuming]->pfn)
> >>> +				break;
> >>>   		}
> >>>
> >>>   		if ((num_dumped % per) == 0)
> >>>   			print_progress(PROGRESS_COPY, num_dumped, info->num_dumpable);
> >>>
> >>> -		/* next pfn is found, refresh last here */
> >>> -		last = new;
> >>> -		consuming_pfn++;
> >>> -		info->consumed_pfn++;
> >>> -		page_data_buf[index].ready = 0;
> >>> -
> >>> -		if (page_data_buf[index].dumpable == FALSE)
> >>> -			goto unlock;
> >>> -
> >>>   		num_dumped++;
> >>>
> >>> -		if (page_data_buf[index].zero == TRUE) {
> >>> +
> >>> +		if (info->page_flag_buf[consuming]->zero == TRUE) {
> >>>   			if (!write_cache(cd_header, pd_zero, sizeof(page_desc_t)))
> >>>   				goto out;
> >>>   			pfn_zero++;
> >>>   		} else {
> >>> +			index = info->page_flag_buf[consuming]->index;
> >>>   			pd.flags      = page_data_buf[index].flags;
> >>>   			pd.size       = page_data_buf[index].size;
> >>>   			pd.page_flags = 0;
> >>> @@ -7420,12 +7507,12 @@ write_kdump_pages_parallel_cyclic(struct cache_data *cd_header,
> >>>   			 */
> >>>   			if (!write_cache(cd_page, page_data_buf[index].buf, pd.size))
> >>>   				goto out;
> >>> -
> >>> +			page_data_buf[index].used = 0;
> >>>   		}
> >>> -unlock:
> >>> -		pthread_mutex_unlock(&page_data_buf[index].mutex);
> >>> +		info->page_flag_buf[consuming]->ready = FLAG_UNUSED;
> >>> +		info->page_flag_buf[consuming] = info->page_flag_buf[consuming]->next;
> >>>   	}
> >>> -
> >>> +finish:
> >>>   	ret = TRUE;
> >>>   	/*
> >>>   	 * print [100 %]
> >>> @@ -7464,7 +7551,7 @@ out:
> >>>   	}
> >>>
> >>>   	if (page_data_buf != NULL) {
> >>> -		for (i = 0; i < page_data_num; i++) {
> >>> +		for (i = 0; i < page_buf_num; i++) {
> >>>   			pthread_mutex_destroy(&page_data_buf[i].mutex);
> >>>   		}
> >>>   	}
> >>> @@ -7564,6 +7651,7 @@ write_kdump_pages_cyclic(struct cache_data *cd_header, struct cache_data *cd_pag
> >>>   		num_dumped++;
> >>>   		if (!read_pfn(pfn, buf))
> >>>   			goto out;
> >>> +
> >>>   		filter_data_buffer(buf, pfn_to_paddr(pfn), info->page_size);
> >>>
> >>>   		/*
> >>> diff --git a/makedumpfile.h b/makedumpfile.h
> >>> index e0b5bbf..8a9a5b2 100644
> >>> --- a/makedumpfile.h
> >>> +++ b/makedumpfile.h
> >>> @@ -977,7 +977,7 @@ typedef unsigned long long int ulonglong;
> >>>   #define PAGE_DATA_NUM	(50)
> >>>   #define WAIT_TIME	(60 * 10)
> >>>   #define PTHREAD_FAIL	((void *)-2)
> >>> -#define NUM_BUFFERS	(50)
> >>> +#define NUM_BUFFERS	(20)
> >>>
> >>>   struct mmap_cache {
> >>>   	char	*mmap_buf;
> >>> @@ -985,28 +985,36 @@ struct mmap_cache {
> >>>   	off_t   mmap_end_offset;
> >>>   };
> >>>
> >>> +enum {
> >>> +	FLAG_UNUSED,
> >>> +	FLAG_READY,
> >>> +	FLAG_FILLING
> >>> +};
> >>> +struct page_flag {
> >>> +	mdf_pfn_t pfn;
> >>> +	char zero;
> >>> +	char ready;
> >>> +	short index;
> >>> +	struct page_flag *next;
> >>> +};
> >>> +
> >>>   struct page_data
> >>>   {
> >>> -	mdf_pfn_t pfn;
> >>> -	int dumpable;
> >>> -	int zero;
> >>> -	unsigned int flags;
> >>> +	pthread_mutex_t mutex;
> >>>   	long size;
> >>>   	unsigned char *buf;
> >>> -	pthread_mutex_t mutex;
> >>> -	/*
> >>> -	 * whether the page_data is ready to be consumed
> >>> -	 */
> >>> -	int ready;
> >>> +	int flags;
> >>> +	int used;
> >>>   };
> >>>
> >>>   struct thread_args {
> >>>   	int thread_num;
> >>>   	unsigned long len_buf_out;
> >>>   	mdf_pfn_t start_pfn, end_pfn;
> >>> -	int page_data_num;
> >>> +	int page_buf_num;
> >>>   	struct cycle *cycle;
> >>>   	struct page_data *page_data_buf;
> >>> +	struct page_flag *page_flag_buf;
> >>>   };
> >>>
> >>>   /*
> >>> @@ -1295,6 +1303,7 @@ struct DumpInfo {
> >>>   	pthread_t **threads;
> >>>   	struct thread_args *kdump_thread_args;
> >>>   	struct page_data *page_data_buf;
> >>> +	struct page_flag **page_flag_buf;
> >>>   	pthread_rwlock_t usemmap_rwlock;
> >>>   	mdf_pfn_t current_pfn;
> >>>   	pthread_mutex_t current_pfn_mutex;
> >>> --
> >>> 1.8.3.1
> >>>
> >>>
> >>>
> >>>
> >>> _______________________________________________
> >>> kexec mailing list
> >>> kexec at lists.infradead.org
> >>> http://lists.infradead.org/mailman/listinfo/kexec
> >>
> >> _______________________________________________
> >> kexec mailing list
> >> kexec at lists.infradead.org
> >> http://lists.infradead.org/mailman/listinfo/kexec
> >
> >
> 



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