From 047487c947e8b96b94579c3a33207bd4e266b4c6 Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 21 Oct 2021 00:19:46 +0100 Subject: cachefiles: Implement the I/O routines Implement the I/O routines for cachefiles. There are two sets of routines here: preparation and actual I/O. Preparation for read involves looking to see whether there is data present, and how much. Netfslib tells us what it wants us to do and we have the option of adjusting shrinking and telling it whether to read from the cache, download from the server or simply clear a region. Preparation for write involves checking for space and defending against possibly running short of space, if necessary punching out a hole in the file so that we don't leave old data in the cache if we update the coherency information. Then there's a read routine and a write routine. They wait for the cookie state to move to something appropriate and then start a potentially asynchronous direct I/O operation upon it. Changes ======= ver #2: - Fix a misassigned variable[1]. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/YaZOCk9zxApPattb@archlinux-ax161/ [1] Link: https://lore.kernel.org/r/163819647945.215744.17827962047487125939.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906954666.143852.1504887120569779407.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163967163110.1823006.9206718511874339672.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/164021562168.640689.8802250542405732391.stgit@warthog.procyon.org.uk/ # v4 --- include/trace/events/cachefiles.h | 121 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 121 insertions(+) (limited to 'include/trace') diff --git a/include/trace/events/cachefiles.h b/include/trace/events/cachefiles.h index 98b1eee4a7a8..ab1376ebc3ab 100644 --- a/include/trace/events/cachefiles.h +++ b/include/trace/events/cachefiles.h @@ -61,6 +61,17 @@ enum cachefiles_trunc_trace { cachefiles_trunc_shrink, }; +enum cachefiles_prepare_read_trace { + cachefiles_trace_read_after_eof, + cachefiles_trace_read_found_hole, + cachefiles_trace_read_found_part, + cachefiles_trace_read_have_data, + cachefiles_trace_read_no_data, + cachefiles_trace_read_no_file, + cachefiles_trace_read_seek_error, + cachefiles_trace_read_seek_nxio, +}; + enum cachefiles_error_trace { cachefiles_trace_fallocate_error, cachefiles_trace_getxattr_error, @@ -125,6 +136,16 @@ enum cachefiles_error_trace { EM(cachefiles_trunc_expand_tmpfile, "EXPTMP") \ E_(cachefiles_trunc_shrink, "SHRINK") +#define cachefiles_prepare_read_traces \ + EM(cachefiles_trace_read_after_eof, "after-eof ") \ + EM(cachefiles_trace_read_found_hole, "found-hole") \ + EM(cachefiles_trace_read_found_part, "found-part") \ + EM(cachefiles_trace_read_have_data, "have-data ") \ + EM(cachefiles_trace_read_no_data, "no-data ") \ + EM(cachefiles_trace_read_no_file, "no-file ") \ + EM(cachefiles_trace_read_seek_error, "seek-error") \ + E_(cachefiles_trace_read_seek_nxio, "seek-enxio") + #define cachefiles_error_traces \ EM(cachefiles_trace_fallocate_error, "fallocate") \ EM(cachefiles_trace_getxattr_error, "getxattr") \ @@ -157,6 +178,7 @@ cachefiles_obj_kill_traces; cachefiles_obj_ref_traces; cachefiles_coherency_traces; cachefiles_trunc_traces; +cachefiles_prepare_read_traces; cachefiles_error_traces; /* @@ -343,6 +365,105 @@ TRACE_EVENT(cachefiles_coherency, __entry->content) ); +TRACE_EVENT(cachefiles_prep_read, + TP_PROTO(struct netfs_read_subrequest *sreq, + enum netfs_read_source source, + enum cachefiles_prepare_read_trace why, + ino_t cache_inode), + + TP_ARGS(sreq, source, why, cache_inode), + + TP_STRUCT__entry( + __field(unsigned int, rreq ) + __field(unsigned short, index ) + __field(unsigned short, flags ) + __field(enum netfs_read_source, source ) + __field(enum cachefiles_prepare_read_trace, why ) + __field(size_t, len ) + __field(loff_t, start ) + __field(unsigned int, netfs_inode ) + __field(unsigned int, cache_inode ) + ), + + TP_fast_assign( + __entry->rreq = sreq->rreq->debug_id; + __entry->index = sreq->debug_index; + __entry->flags = sreq->flags; + __entry->source = source; + __entry->why = why; + __entry->len = sreq->len; + __entry->start = sreq->start; + __entry->netfs_inode = sreq->rreq->inode->i_ino; + __entry->cache_inode = cache_inode; + ), + + TP_printk("R=%08x[%u] %s %s f=%02x s=%llx %zx ni=%x b=%x", + __entry->rreq, __entry->index, + __print_symbolic(__entry->source, netfs_sreq_sources), + __print_symbolic(__entry->why, cachefiles_prepare_read_traces), + __entry->flags, + __entry->start, __entry->len, + __entry->netfs_inode, __entry->cache_inode) + ); + +TRACE_EVENT(cachefiles_read, + TP_PROTO(struct cachefiles_object *obj, + struct inode *backer, + loff_t start, + size_t len), + + TP_ARGS(obj, backer, start, len), + + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(unsigned int, backer ) + __field(size_t, len ) + __field(loff_t, start ) + ), + + TP_fast_assign( + __entry->obj = obj->debug_id; + __entry->backer = backer->i_ino; + __entry->start = start; + __entry->len = len; + ), + + TP_printk("o=%08x b=%08x s=%llx l=%zx", + __entry->obj, + __entry->backer, + __entry->start, + __entry->len) + ); + +TRACE_EVENT(cachefiles_write, + TP_PROTO(struct cachefiles_object *obj, + struct inode *backer, + loff_t start, + size_t len), + + TP_ARGS(obj, backer, start, len), + + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(unsigned int, backer ) + __field(size_t, len ) + __field(loff_t, start ) + ), + + TP_fast_assign( + __entry->obj = obj->debug_id; + __entry->backer = backer->i_ino; + __entry->start = start; + __entry->len = len; + ), + + TP_printk("o=%08x b=%08x s=%llx l=%zx", + __entry->obj, + __entry->backer, + __entry->start, + __entry->len) + ); + TRACE_EVENT(cachefiles_trunc, TP_PROTO(struct cachefiles_object *obj, struct inode *backer, loff_t from, loff_t to, enum cachefiles_trunc_trace why), -- cgit v1.2.3-58-ga151