mirror/postgresql
2
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2025-03-13 19:57:53 +08:00
Code Issues Packages Projects Releases Wiki Activity

Correctly align page's images in generic wal API

Browse Source 
Page image should be MAXALIGN'ed because existing code could directly align
pointers in page instead of align offset from beginning of page.

Found during play with indexes as extenstion, Alexander Korotkov and me
This commit is contained in:
Teodor Sigaev 2016-05-17 00:01:35 +03:00
parent 02a568a027
commit 7c8345f67f
1 changed files with 13 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
src/backend/access/transam/generic_xlog.c
View File

@ -52,7 +52,9 @@ typedef struct
Buffer buffer; /* registered buffer */
int flags; /* flags for this buffer */
int deltaLen; /* space consumed in delta field */
char image[BLCKSZ]; /* copy of page image for modification */
char *image; /* copy of page image for modification,
* do not do it in-place to have aligned
* memory chunk */
char delta[MAX_DELTA_SIZE]; /* delta between page images */
} PageData;
@ -268,7 +270,15 @@ GenericXLogStart(Relation relation)
state->isLogged = RelationNeedsWAL(relation);
for (i = 0; i < MAX_GENERIC_XLOG_PAGES; i++)
{
/*
* pre-alloc page's images to prevent allocation in
* GenericXLogRegisterBuffer() which could be called in different
* memory context(s)
*/
state->pages[i].image = palloc(BLCKSZ);
state->pages[i].buffer = InvalidBuffer;
}
return state;
}
@ -422,6 +432,8 @@ GenericXLogFinish(GenericXLogState *state)
lsn = InvalidXLogRecPtr;
}
for (i = 0; i < MAX_GENERIC_XLOG_PAGES; i++)
pfree(state->pages[i].image);
pfree(state);
return lsn;