From c232bf58cb1169f1bd80c519e2cc4218e525a556 Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Tue, 22 Aug 2017 18:02:12 +0100 Subject: migration: Report when bdrv_inactivate_all fails If the bdrv_inactivate_all fails near the end of the migration, the migration will fail and often the only diagnostics in the log are an I/O error which you can't distinguish from an error on the socket connection. Add an error so we know when it's actually a block problem. Signed-off-by: Dr. David Alan Gilbert Message-Id: <20170822170212.27347-1-dgilbert@redhat.com> Reviewed-by: Peter Xu Reviewed-by: Stefan Hajnoczi Signed-off-by: Dr. David Alan Gilbert --- migration/savevm.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/migration/savevm.c b/migration/savevm.c index fdd15fa0a7..7a55023d1a 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1157,6 +1157,8 @@ int qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only, * bdrv_invalidate_cache_all() on the other end won't fail. */ ret = bdrv_inactivate_all(); if (ret) { + error_report("%s: bdrv_inactivate_all() failed (%d)", + __func__, ret); qemu_file_set_error(f, ret); return ret; } -- cgit v1.2.3 From d0834eb5393501fe8efe350db4dc638f23a218ff Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Thu, 27 Jul 2017 11:46:14 +0200 Subject: xbzrle: Drop unused cache_resize() Unused since commit fd8cec XBZRLE: Fix qemu crash when resize the xbzrle cache. Cc: Juan Quintela Cc: "Dr. David Alan Gilbert" Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Eric Blake Reviewed-by: Amit Shah Reviewed-by: Juan Quintela Signed-off-by: Markus Armbruster Message-Id: <1501148776-16890-2-git-send-email-armbru@redhat.com> Signed-off-by: Dr. David Alan Gilbert --- migration/page_cache.c | 56 -------------------------------------------------- migration/page_cache.h | 11 ---------- 2 files changed, 67 deletions(-) diff --git a/migration/page_cache.c b/migration/page_cache.c index 5f8578736e..ba984c4858 100644 --- a/migration/page_cache.c +++ b/migration/page_cache.c @@ -178,59 +178,3 @@ int cache_insert(PageCache *cache, uint64_t addr, const uint8_t *pdata, return 0; } - -int64_t cache_resize(PageCache *cache, int64_t new_num_pages) -{ - PageCache *new_cache; - int64_t i; - - CacheItem *old_it, *new_it; - - g_assert(cache); - - /* cache was not inited */ - if (cache->page_cache == NULL) { - return -1; - } - - /* same size */ - if (pow2floor(new_num_pages) == cache->max_num_items) { - return cache->max_num_items; - } - - new_cache = cache_init(new_num_pages, cache->page_size); - if (!(new_cache)) { - DPRINTF("Error creating new cache\n"); - return -1; - } - - /* move all data from old cache */ - for (i = 0; i < cache->max_num_items; i++) { - old_it = &cache->page_cache[i]; - if (old_it->it_addr != -1) { - /* check for collision, if there is, keep MRU page */ - new_it = cache_get_by_addr(new_cache, old_it->it_addr); - if (new_it->it_data && new_it->it_age >= old_it->it_age) { - /* keep the MRU page */ - g_free(old_it->it_data); - } else { - if (!new_it->it_data) { - new_cache->num_items++; - } - g_free(new_it->it_data); - new_it->it_data = old_it->it_data; - new_it->it_age = old_it->it_age; - new_it->it_addr = old_it->it_addr; - } - } - } - - g_free(cache->page_cache); - cache->page_cache = new_cache->page_cache; - cache->max_num_items = new_cache->max_num_items; - cache->num_items = new_cache->num_items; - - g_free(new_cache); - - return cache->max_num_items; -} diff --git a/migration/page_cache.h b/migration/page_cache.h index 10ed53274c..4fadd0c501 100644 --- a/migration/page_cache.h +++ b/migration/page_cache.h @@ -72,15 +72,4 @@ uint8_t *get_cached_data(const PageCache *cache, uint64_t addr); int cache_insert(PageCache *cache, uint64_t addr, const uint8_t *pdata, uint64_t current_age); -/** - * cache_resize: resize the page cache. In case of size reduction the extra - * pages will be freed - * - * Returns -1 on error new cache size on success - * - * @cache pointer to the PageCache struct - * @num_pages: new page cache size (in pages) - */ -int64_t cache_resize(PageCache *cache, int64_t num_pages); - #endif -- cgit v1.2.3 From 43c64a093dbe8bffa4eb774685dee535bdffaffb Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Thu, 27 Jul 2017 11:46:15 +0200 Subject: host-utils: Proactively fix pow2floor(), switch to unsigned The function's stated contract is simple enough: "round down to the nearest power of 2". Suggests the domain is the representable numbers >= 1, because that's the smallest power of two. The implementation doesn't check for domain errors, but returns garbage instead: * For negative arguments, pow2floor() returns -2^63, which is not even a power of two, let alone the nearest one. What sort of works is passing *unsigned* arguments >= 2^63. The implicit conversion to signed is implementation defined, but commonly yields the (negative) two's complement. pow2floor() then returns -2^63. Callers that convert that back to unsigned get the correct value 2^63. * For a zero argument, pow2floor() shifts right by 64. Undefined behavior. Common actual behavior is to shift by 0, yielding -2^63. Fix by switching from int64_t to uint64_t and amending the contract to map zero to zero. Callers are fine with that: * memory_access_size() This function makes no sense unless the argument is positive and the return value fits into int. * raw_refresh_limits() Passes an int between 1 and BDRV_REQUEST_MAX_BYTES. * iscsi_refresh_limits() Passes an integer between 0 and INT_MAX, converts the result to uint32_t. Passing zero would be undefined behavior, but commonly yield zero. The patch gives us the zero without the undefined behavior. * cache_init() Passes a positive int64_t argument. * xbzrle_cache_resize() Passes a positive int64_t argument (>= TARGET_PAGE_SIZE, actually). * spapr_node0_size() Passes a positive uint64_t argument, and converts the result to hwaddr, i.e. uint64_t. * spapr_populate_memory() Passes a positive hwaddr argument, and converts the result to hwaddr. Cc: Juan Quintela Cc: Dr. David Alan Gilbert Cc: Eric Blake Cc: Peter Maydell Cc: Alexey Kardashevskiy Signed-off-by: Markus Armbruster Message-Id: <1501148776-16890-3-git-send-email-armbru@redhat.com> Reviewed-by: Eric Blake Signed-off-by: Dr. David Alan Gilbert --- include/qemu/host-utils.h | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/include/qemu/host-utils.h b/include/qemu/host-utils.h index 95cf4f4163..6c6005f5cf 100644 --- a/include/qemu/host-utils.h +++ b/include/qemu/host-utils.h @@ -369,13 +369,16 @@ static inline bool is_power_of_2(uint64_t value) return !(value & (value - 1)); } -/* round down to the nearest power of 2*/ -static inline int64_t pow2floor(int64_t value) +/** + * Return @value rounded down to the nearest power of two or zero. + */ +static inline uint64_t pow2floor(uint64_t value) { - if (!is_power_of_2(value)) { - value = 0x8000000000000000ULL >> clz64(value); + if (!value) { + /* Avoid undefined shift by 64 */ + return 0; } - return value; + return 0x8000000000000000ull >> clz64(value); } /* round up to the nearest power of 2 (0 if overflow) */ -- cgit v1.2.3 From 362aaf14576d2bc3f0117b87cfb595d48cda3d64 Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Thu, 27 Jul 2017 11:46:16 +0200 Subject: host-utils: Simplify pow2ceil() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Radim Krčmář Signed-off-by: Markus Armbruster Message-Id: <1501148776-16890-4-git-send-email-armbru@redhat.com> Reviewed-by: Eric Blake Signed-off-by: Dr. David Alan Gilbert --- include/qemu/host-utils.h | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/include/qemu/host-utils.h b/include/qemu/host-utils.h index 6c6005f5cf..5ac621cf1f 100644 --- a/include/qemu/host-utils.h +++ b/include/qemu/host-utils.h @@ -381,18 +381,23 @@ static inline uint64_t pow2floor(uint64_t value) return 0x8000000000000000ull >> clz64(value); } -/* round up to the nearest power of 2 (0 if overflow) */ +/* + * Return @value rounded up to the nearest power of two modulo 2^64. + * This is *zero* for @value > 2^63, so be careful. + */ static inline uint64_t pow2ceil(uint64_t value) { - uint8_t nlz = clz64(value); - - if (is_power_of_2(value)) { - return value; - } - if (!nlz) { - return 0; + int n = clz64(value - 1); + + if (!n) { + /* + * @value - 1 has no leading zeroes, thus @value - 1 >= 2^63 + * Therefore, either @value == 0 or @value > 2^63. + * If it's 0, return 1, else return 0. + */ + return !value; } - return 1ULL << (64 - nlz); + return 0x8000000000000000ull >> (n - 1); } /** -- cgit v1.2.3 From 505d786f8f627ec5eccfee79a6a8f3a0e0bc3fa2 Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Fri, 4 Aug 2017 18:50:11 +0100 Subject: runstate/migrate: Two more transitions There's a race if someone does a 'stop' near the end of migrate; the migration process goes through two runstates: 'finish migrate' 'postmigrate' If the user issues a 'stop' between the two we end up with invalid state transitions. Add the transitions as valid. Signed-off-by: Dr. David Alan Gilbert Message-Id: <20170804175011.21944-1-dgilbert@redhat.com> Reviewed-by: Peter Xu Reviewed-by: Juan Quintela Signed-off-by: Dr. David Alan Gilbert --- vl.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/vl.c b/vl.c index e75757f977..fb1f05b937 100644 --- a/vl.c +++ b/vl.c @@ -621,6 +621,7 @@ static const RunStateTransition runstate_transitions_def[] = { { RUN_STATE_PAUSED, RUN_STATE_RUNNING }, { RUN_STATE_PAUSED, RUN_STATE_FINISH_MIGRATE }, + { RUN_STATE_PAUSED, RUN_STATE_POSTMIGRATE }, { RUN_STATE_PAUSED, RUN_STATE_PRELAUNCH }, { RUN_STATE_PAUSED, RUN_STATE_COLO}, @@ -633,6 +634,7 @@ static const RunStateTransition runstate_transitions_def[] = { { RUN_STATE_PRELAUNCH, RUN_STATE_INMIGRATE }, { RUN_STATE_FINISH_MIGRATE, RUN_STATE_RUNNING }, + { RUN_STATE_FINISH_MIGRATE, RUN_STATE_PAUSED }, { RUN_STATE_FINISH_MIGRATE, RUN_STATE_POSTMIGRATE }, { RUN_STATE_FINISH_MIGRATE, RUN_STATE_PRELAUNCH }, { RUN_STATE_FINISH_MIGRATE, RUN_STATE_COLO}, -- cgit v1.2.3 From 5089e1862fe80b6f23ba4c494e2902cbe3d9d48e Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Fri, 25 Aug 2017 15:19:39 +0100 Subject: migration: Reset rather than destroy main_thread_load_event migration_incoming_state_destroy doesn't really destroy, it cleans up. After a loadvm it's called, but the loadvm command can be run twice, and so destroying an init-once mutex breaks on the second loadvm. Reported-by: Stafford Horne Signed-off-by: Dr. David Alan Gilbert Message-Id: <20170825141940.20740-2-dgilbert@redhat.com> Reviewed-by: Peter Xu Tested-by: Stafford Horne Signed-off-by: Dr. David Alan Gilbert --- migration/migration.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/migration/migration.c b/migration/migration.c index 1a2b3ebd1a..9838ccc885 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -166,7 +166,7 @@ void migration_incoming_state_destroy(void) mis->from_src_file = NULL; } - qemu_event_destroy(&mis->main_thread_load_event); + qemu_event_reset(&mis->main_thread_load_event); } static void migrate_generate_event(int new_state) -- cgit v1.2.3 From 04583a9e8fbeb2c5c0607327b853b306aef7465f Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Fri, 25 Aug 2017 15:19:40 +0100 Subject: snapshot/tests: Try loadvm twice It's legal to loadvm twice, modify the existing save/loadvm test to do it twice. Signed-off-by: Dr. David Alan Gilbert Message-Id: <20170825141940.20740-3-dgilbert@redhat.com> Reviewed-by: Peter Xu Signed-off-by: Dr. David Alan Gilbert --- tests/qemu-iotests/068 | 2 +- tests/qemu-iotests/068.out | 4 ++++ 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/tests/qemu-iotests/068 b/tests/qemu-iotests/068 index cfa0f2aed5..e7fca6a494 100755 --- a/tests/qemu-iotests/068 +++ b/tests/qemu-iotests/068 @@ -78,7 +78,7 @@ for extra_args in \ # Give qemu some time to boot before saving the VM state { sleep 1; printf "savevm 0\nquit\n"; } | _qemu $extra_args # Now try to continue from that VM state (this should just work) - echo quit | _qemu $extra_args -loadvm 0 + { sleep 1; printf "loadvm 0\nloadvm 0\nquit\n"; } | _qemu $extra_args -S done # success, all done diff --git a/tests/qemu-iotests/068.out b/tests/qemu-iotests/068.out index aa063cf711..f07a938a38 100644 --- a/tests/qemu-iotests/068.out +++ b/tests/qemu-iotests/068.out @@ -7,6 +7,8 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm 0 (qemu) quit QEMU X.Y.Z monitor - type 'help' for more information +(qemu) loadvm 0 +(qemu) loadvm 0 (qemu) quit === Saving and reloading a VM state to/from a qcow2 image (-object iothread,id=iothread0 -set device.hba0.iothread=iothread0) === @@ -16,5 +18,7 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm 0 (qemu) quit QEMU X.Y.Z monitor - type 'help' for more information +(qemu) loadvm 0 +(qemu) loadvm 0 (qemu) quit *** done -- cgit v1.2.3 From a31fedeed764ce0b0d6097d4334c5770e74641a0 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Wed, 30 Aug 2017 16:32:01 +0800 Subject: migration: dump str in migrate_set_state trace Strings are more readable for debugging. Reviewed-by: Dr. David Alan Gilbert Signed-off-by: Peter Xu Message-Id: <1504081950-2528-5-git-send-email-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert Fixed up merge with 977c73 --- migration/migration.c | 3 ++- migration/trace-events | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/migration/migration.c b/migration/migration.c index 9838ccc885..959e8ec88e 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -913,8 +913,9 @@ void qmp_migrate_start_postcopy(Error **errp) void migrate_set_state(int *state, int old_state, int new_state) { + assert(new_state < MIGRATION_STATUS__MAX); if (atomic_cmpxchg(state, old_state, new_state) == old_state) { - trace_migrate_set_state(new_state); + trace_migrate_set_state(MigrationStatus_str(new_state)); migrate_generate_event(new_state); } } diff --git a/migration/trace-events b/migration/trace-events index 7a3b5144ff..d2910a6e7b 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -80,7 +80,7 @@ ram_save_queue_pages(const char *rbname, size_t start, size_t len) "%s: start: 0 # migration/migration.c await_return_path_close_on_source_close(void) "" await_return_path_close_on_source_joining(void) "" -migrate_set_state(int new_state) "new state %d" +migrate_set_state(const char *new_state) "new state %s" migrate_fd_cleanup(void) "" migrate_fd_error(const char *error_desc) "error=%s" migrate_fd_cancel(void) "" -- cgit v1.2.3