> Maybe something like this: > > https://paste.fedoraproject.org/paste/CptGkmoRutBKYjno5FiSjg/
That looks like it should fix the problem. Frank > On 10/23/2017 10:13 AM, Malahal Naineni wrote: > > Let us say we have X/Y path in the file system. We have attr_lock and > > content_lock on each object. The locks we are interested here are > > attr_lock on X (hear after referred to as AX) and content_lock on X > > (hear after CX). Similarly we have AY and CY for object named Y. > > > > 1. Thread 50 (lookup called for X ) takes AX and waits for CX (attr_lock > > followed by content_lock is the expected order) > > > > 2. Thread 251 (readdirplus on X) takes CX, AY and then waits for CY for > > processing object Y > > > > 3. Thread 132 (readdirplus on Y) takes CY, and then waits for AX (this > > is due to lookup of parent) > > > > Classic philosopher's problem: 1 waits for 2, 2 waits for 3 and then 3 > > waits for 1. The lock ordering for attr_lock and content_lock for an > > object is attr_lock followed by content_lock. We can assume that > > parent locks should be acquired before the child locks, but DOTDOT > > appears as a child in readdirplus/readdir. If we can handle parent > > differently, we might be OK. Any help would be appreciated. > > > > Regards, Malahal. > > > > (gdb) thread 50 > > [Switching to thread 50 (Thread 0x3fff6cffe850 (LWP 37851))] > > #0 0x00003fff8a50089c in .__pthread_rwlock_wrlock () from > > /lib64/libpthread.so.0 > > (gdb) bt > > #0 0x00003fff8a50089c in .__pthread_rwlock_wrlock () from > > /lib64/libpthread.so.0 > > #1 0x00000000101adaa4 in mdcache_refresh_attrs (entry=0x3ffccc0541f0, > > need_acl=false, invalidate=true) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_handle.c:1187 > > #2 0x00000000101ae1b0 in mdcache_getattrs (obj_hdl=0x3ffccc054228, > > attrs_out=0x3fff6cffcfb8) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_handle.c:1228 > > #3 0x00000000100b9fdc in nfs_SetPostOpAttr (obj=0x3ffccc054228, > > Fattr=0x3ffe64050dc8, attrs=0x0) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/Protocols/NF > > S/nfs_proto_tools.c:91 > > #4 0x00000000100c6ba8 in nfs3_lookup (arg=0x3ffa9ff04780, > > req=0x3ffa9ff03f78, res=0x3ffe64050d50) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/Protocols/NF > > S/nfs3_lookup.c:131 > > #5 0x0000000010065220 in nfs_rpc_execute (reqdata=0x3ffa9ff03f50) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/MainNFSD/nfs > > _worker_thread.c:1290 > > #6 0x0000000010065c9c in worker_run (ctx=0x10013c1d3f0) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/MainNFSD/nfs > > _worker_thread.c:1562 > > #7 0x00000000101670f4 in fridgethr_start_routine (arg=0x10013c1d3f0) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1-Source/support/frid > > gethr.c:550 > > #8 0x00003fff8a4fc2bc in .start_thread () from /lib64/libpthread.so.0 > > #9 0x00003fff8a31b304 in .__clone () from /lib64/libc.so.6 > > (gdb) frame 1 > > #1 0x00000000101adaa4 in mdcache_refresh_attrs (entry=0x3ffccc0541f0, > > need_acl=false, invalidate=true) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_handle.c:1187 > > 1187PTHREAD_RWLOCK_wrlock(&entry->content_lock); > > (gdb) p entry > > $1 = (mdcache_entry_t *) 0x3ffccc0541f0 > > (gdb) p entry->content_lock > > $2 = {__data = {__lock = 0, __nr_readers = 1, __readers_wakeup = 2408, > > __writer_wakeup = 4494, __nr_readers_queued = 0, > > __nr_writers_queued = 6, __writer = 0, __shared = 0, __pad1 = 0, > > __pad2 = 0, __flags = 0}, > > __size = > > > "\000\000\000\000\000\000\000\001\000\000\th\000\000\021\216\000\000\0 > > 00\000\000\000\000\006", '\000' <repeats 31 times>, __align = 1} > > (gdb) thread 251 > > [Switching to thread 251 (Thread 0x3fff2e7fe850 (LWP 37976))] > > #0 0x00003fff8a50089c in .__pthread_rwlock_wrlock () from > > /lib64/libpthread.so.0 > > (gdb) bt > > #0 0x00003fff8a50089c in .__pthread_rwlock_wrlock () from > > /lib64/libpthread.so.0 > > #1 0x00000000101adaa4 in mdcache_refresh_attrs (entry=0x3ffc30041bd0, > > need_acl=false, invalidate=true) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_handle.c:1187 > > #2 0x00000000101ae1b0 in mdcache_getattrs (obj_hdl=0x3ffc30041c08, > > attrs_out=0x3fff2e7fcb58) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_handle.c:1228 > > #3 0x00000000101c0f50 in mdcache_readdir_chunked > > (directory=0x3ffccc0541f0, whence=1298220731, > > dir_state=0x3fff2e7fcee8, cb=@0x1024b040: 0x1003f524 > > <populate_dirent>, attrmask=122830, eod_met=0x3fff2e7fd01c) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_helpers.c:3047 > > #4 0x00000000101ab998 in mdcache_readdir (dir_hdl=0x3ffccc054228, > > whence=0x3fff2e7fcfa0, dir_state=0x3fff2e7fcee8, > > cb=@0x1024b040: 0x1003f524 <populate_dirent>, attrmask=122830, > > eod_met=0x3fff2e7fd01c) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_handle.c:637 > > #5 0x0000000010040090 in fsal_readdir (directory=0x3ffccc054228, > > cookie=1298220731, nbfound=0x3fff2e7fd018, > > eod_met=0x3fff2e7fd01c, attrmask=122830, cb=@0x10250bb0: > > 0x100cabf4 <nfs3_readdirplus_callback>, > > opaque=0x3fff2e7fd038) at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/fsal_he > > lper.c:1504 > > #6 0x00000000100ca90c in nfs3_readdirplus (arg=0x3ffa14114820, > > req=0x3ffa14114018, res=0x3ffc6c0540c0) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/Protocols/NF > > S/nfs3_readdirplus.c:309 > > #7 0x0000000010065220 in nfs_rpc_execute (reqdata=0x3ffa14113ff0) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/MainNFSD/nfs > > _worker_thread.c:1290 > > #8 0x0000000010065c9c in worker_run (ctx=0x10013c41c30) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/MainNFSD/nfs > > _worker_thread.c:1562 > > #9 0x00000000101670f4 in fridgethr_start_routine (arg=0x10013c41c30) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1-Source/support/frid > > gethr.c:550 > > #10 0x00003fff8a4fc2bc in .start_thread () from /lib64/libpthread.so.0 > > #11 0x00003fff8a31b304 in .__clone () from /lib64/libc.so.6 > > (gdb) frame 1 > > #1 0x00000000101adaa4 in mdcache_refresh_attrs (entry=0x3ffc30041bd0, > > need_acl=false, invalidate=true) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_handle.c:1187 > > 1187PTHREAD_RWLOCK_wrlock(&entry->content_lock); > > (gdb) p entry > > $3 = (mdcache_entry_t *) 0x3ffc30041bd0 > > (gdb) p entry->content_lock > > $4 = {__data = {__lock = 0, __nr_readers = 1, __readers_wakeup = 3, > > __writer_wakeup = 2, __nr_readers_queued = 0, > > __nr_writers_queued = 1, __writer = 0, __shared = 0, __pad1 = 0, > > __pad2 = 0, __flags = 0}, > > __size = > > > "\000\000\000\000\000\000\000\001\000\000\000\003\000\000\000\002\000 > \ > > 000\000\000\000\000\000\001", '\000' <repeats 31 times>, __align = 1} > > (gdb) thread 132 > > [Switching to thread 132 (Thread 0x3fff1b7fe850 (LWP 38014))] > > #0 0x00003fff8a500428 in .__pthread_rwlock_rdlock () from > > /lib64/libpthread.so.0 > > (gdb) bt > > #0 0x00003fff8a500428 in .__pthread_rwlock_rdlock () from > > /lib64/libpthread.so.0 > > #1 0x00000000101adda0 in mdcache_getattrs (obj_hdl=0x3ffccc054228, > > attrs_out=0x3fff1b7fd140) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_handle.c:1212 > > #2 0x00000000101b7280 in get_optional_attrs (obj_hdl=0x3ffccc054228, > > attrs_out=0x3fff1b7fd140) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_helpers.c:135 > > #3 0x00000000101ba3d8 in mdcache_locate_host > (fh_desc=0x3ffc30042148, > > export=0x10010c6b710, entry=0x3fff1b7fceb0, > > attrs_out=0x3fff1b7fd140) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_helpers.c:972 > > #4 0x00000000101bb1f8 in mdc_lookup (mdc_parent=0x3ffc30041bd0, > > name=0x101dd8e0 "..", uncached=true, > > new_entry=0x3fff1b7fceb0, attrs_out=0x3fff1b7fd140) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_helpers.c:1213 > > #5 0x00000000101a9518 in mdcache_lookup (parent=0x3ffc30041c08, > > name=0x101dd8e0 "..", handle=0x3fff1b7fd220, > > attrs_out=0x3fff1b7fd140) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_handle.c:175 > > #6 0x000000001003dba4 in fsal_lookupp (obj=0x3ffc30041c08, > > parent=0x3fff1b7fd220, attrs_out=0x3fff1b7fd140) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/fsal_he > > lper.c:756 > > #7 0x00000000100ca7fc in nfs3_readdirplus (arg=0x3ffef3f05a00, > > req=0x3ffef3f051f8, res=0x3ffbd4058e40) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/Protocols/NF > > S/nfs3_readdirplus.c:281 > > #8 0x0000000010065220 in nfs_rpc_execute (reqdata=0x3ffef3f051d0) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/MainNFSD/nfs > > _worker_thread.c:1290 > > #9 0x0000000010065c9c in worker_run (ctx=0x10013c4d0b0) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/MainNFSD/nfs > > _worker_thread.c:1562 > > #10 0x00000000101670f4 in fridgethr_start_routine (arg=0x10013c4d0b0) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1-Source/support/frid > > gethr.c:550 > > #11 0x00003fff8a4fc2bc in .start_thread () from /lib64/libpthread.so.0 > > #12 0x00003fff8a31b304 in .__clone () from /lib64/libc.so.6 > > (gdb) frame 1 > > #1 0x00000000101adda0 in mdcache_getattrs (obj_hdl=0x3ffccc054228, > > attrs_out=0x3fff1b7fd140) > > at > > /usr/src/debug/nfs-ganesha-2.5.3-ibm008.20M6-0.1.1- > Source/FSAL/Stackab > > le_FSALs/FSAL_MDCACHE/mdcache_handle.c:1212 > > 1212PTHREAD_RWLOCK_rdlock(&entry->attr_lock); > > (gdb) p entry > > $5 = (mdcache_entry_t *) 0x3ffccc0541f0 > > (gdb) p entry->attr_lock > > $6 = {__data = {__lock = 0, __nr_readers = 0, __readers_wakeup = 1306, > > __writer_wakeup = 276, > > __nr_readers_queued = 215, __nr_writers_queued = 0, __writer = > > 37851, __shared = 0, __pad1 = 0, __pad2 = 0, > > __flags = 0}, > > __size = > > > "\000\000\000\000\000\000\000\000\000\000\005\032\000\000\001\024\000 > \ > > 000\000\327\000\000\000\000\000\000\223\333", > > '\000' <repeats 27 times>, __align = 0} > > (gdb) > > > > > > > > ---------------------------------------------------------------------- > > -------- Check out the vibrant tech community on one of the world's > > most engaging tech sites, Slashdot.org! http://sdm.link/slashdot > > > > > > > > _______________________________________________ > > Nfs-ganesha-devel mailing list > > Nfs-ganesha-devel@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/nfs-ganesha-devel > > > > > ---------------------------------------------------------------------------- -- > Check out the vibrant tech community on one of the world's most engaging > tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Nfs-ganesha-devel mailing list > Nfs-ganesha-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/nfs-ganesha-devel --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Nfs-ganesha-devel mailing list Nfs-ganesha-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs-ganesha-devel