From 476ebf77fe8909ded10046edf26685bc28438162 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Wed, 19 Jan 2022 16:09:20 +0800 Subject: migration: Move temp page setup and cleanup into separate functions Temp pages will need to grow if we want to have multiple channels for postcopy, because each channel will need its own temp page to cache huge page data. Before doing that, cleanup the related code. No functional change intended. Since at it, touch up the errno handling a little bit on the setup side. Signed-off-by: Peter Xu Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Juan Quintela Signed-off-by: Juan Quintela --- migration/postcopy-ram.c | 82 ++++++++++++++++++++++++++++++------------------ 1 file changed, 51 insertions(+), 31 deletions(-) diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c index 2176ed6..e662dd0 100644 --- a/migration/postcopy-ram.c +++ b/migration/postcopy-ram.c @@ -523,6 +523,19 @@ int postcopy_ram_incoming_init(MigrationIncomingState *mis) return 0; } +static void postcopy_temp_pages_cleanup(MigrationIncomingState *mis) +{ + if (mis->postcopy_tmp_page) { + munmap(mis->postcopy_tmp_page, mis->largest_page_size); + mis->postcopy_tmp_page = NULL; + } + + if (mis->postcopy_tmp_zero_page) { + munmap(mis->postcopy_tmp_zero_page, mis->largest_page_size); + mis->postcopy_tmp_zero_page = NULL; + } +} + /* * At the end of a migration where postcopy_ram_incoming_init was called. */ @@ -564,14 +577,8 @@ int postcopy_ram_incoming_cleanup(MigrationIncomingState *mis) } } - if (mis->postcopy_tmp_page) { - munmap(mis->postcopy_tmp_page, mis->largest_page_size); - mis->postcopy_tmp_page = NULL; - } - if (mis->postcopy_tmp_zero_page) { - munmap(mis->postcopy_tmp_zero_page, mis->largest_page_size); - mis->postcopy_tmp_zero_page = NULL; - } + postcopy_temp_pages_cleanup(mis); + trace_postcopy_ram_incoming_cleanup_blocktime( get_postcopy_total_blocktime()); @@ -1082,6 +1089,40 @@ retry: return NULL; } +static int postcopy_temp_pages_setup(MigrationIncomingState *mis) +{ + int err; + + mis->postcopy_tmp_page = mmap(NULL, mis->largest_page_size, + PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mis->postcopy_tmp_page == MAP_FAILED) { + err = errno; + mis->postcopy_tmp_page = NULL; + error_report("%s: Failed to map postcopy_tmp_page %s", + __func__, strerror(err)); + return -err; + } + + /* + * Map large zero page when kernel can't use UFFDIO_ZEROPAGE for hugepages + */ + mis->postcopy_tmp_zero_page = mmap(NULL, mis->largest_page_size, + PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mis->postcopy_tmp_zero_page == MAP_FAILED) { + err = errno; + mis->postcopy_tmp_zero_page = NULL; + error_report("%s: Failed to map large zero page %s", + __func__, strerror(err)); + return -err; + } + + memset(mis->postcopy_tmp_zero_page, '\0', mis->largest_page_size); + + return 0; +} + int postcopy_ram_incoming_setup(MigrationIncomingState *mis) { /* Open the fd for the kernel to give us userfaults */ @@ -1122,32 +1163,11 @@ int postcopy_ram_incoming_setup(MigrationIncomingState *mis) return -1; } - mis->postcopy_tmp_page = mmap(NULL, mis->largest_page_size, - PROT_READ | PROT_WRITE, MAP_PRIVATE | - MAP_ANONYMOUS, -1, 0); - if (mis->postcopy_tmp_page == MAP_FAILED) { - mis->postcopy_tmp_page = NULL; - error_report("%s: Failed to map postcopy_tmp_page %s", - __func__, strerror(errno)); + if (postcopy_temp_pages_setup(mis)) { + /* Error dumped in the sub-function */ return -1; } - /* - * Map large zero page when kernel can't use UFFDIO_ZEROPAGE for hugepages - */ - mis->postcopy_tmp_zero_page = mmap(NULL, mis->largest_page_size, - PROT_READ | PROT_WRITE, - MAP_PRIVATE | MAP_ANONYMOUS, - -1, 0); - if (mis->postcopy_tmp_zero_page == MAP_FAILED) { - int e = errno; - mis->postcopy_tmp_zero_page = NULL; - error_report("%s: Failed to map large zero page %s", - __func__, strerror(e)); - return -e; - } - memset(mis->postcopy_tmp_zero_page, '\0', mis->largest_page_size); - trace_postcopy_ram_enable_notify(); return 0; -- cgit v1.1