On 05 May 2022 at 21:34, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@xxxxxxxxxx>
>
> Augment the xfs_db btheight command so that the debugger can display the
> absolute maximum btree height for each btree type.
>
Looks good.
Reviewed-by: Chandan Babu R <chandan.babu@xxxxxxxxxx>
> Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> ---
> db/btheight.c | 73 ++++++++++++++++++++++++++++++++++++++++------
> libxfs/libxfs_api_defs.h | 5 +++
> man/man8/xfs_db.8 | 5 +++
> 3 files changed, 72 insertions(+), 11 deletions(-)
>
>
> diff --git a/db/btheight.c b/db/btheight.c
> index e4cd4eda..0b421ab5 100644
> --- a/db/btheight.c
> +++ b/db/btheight.c
> @@ -24,16 +24,45 @@ static int rmap_maxrecs(struct xfs_mount *mp, int blocklen, int leaf)
>
> struct btmap {
> const char *tag;
> + unsigned int (*maxlevels)(void);
> int (*maxrecs)(struct xfs_mount *mp, int blocklen,
> int leaf);
> } maps[] = {
> - {"bnobt", libxfs_allocbt_maxrecs},
> - {"cntbt", libxfs_allocbt_maxrecs},
> - {"inobt", libxfs_inobt_maxrecs},
> - {"finobt", libxfs_inobt_maxrecs},
> - {"bmapbt", libxfs_bmbt_maxrecs},
> - {"refcountbt", refc_maxrecs},
> - {"rmapbt", rmap_maxrecs},
> + {
> + .tag = "bnobt",
> + .maxlevels = libxfs_allocbt_maxlevels_ondisk,
> + .maxrecs = libxfs_allocbt_maxrecs,
> + },
> + {
> + .tag = "cntbt",
> + .maxlevels = libxfs_allocbt_maxlevels_ondisk,
> + .maxrecs = libxfs_allocbt_maxrecs,
> + },
> + {
> + .tag = "inobt",
> + .maxlevels = libxfs_iallocbt_maxlevels_ondisk,
> + .maxrecs = libxfs_inobt_maxrecs,
> + },
> + {
> + .tag = "finobt",
> + .maxlevels = libxfs_iallocbt_maxlevels_ondisk,
> + .maxrecs = libxfs_inobt_maxrecs,
> + },
> + {
> + .tag = "bmapbt",
> + .maxlevels = libxfs_bmbt_maxlevels_ondisk,
> + .maxrecs = libxfs_bmbt_maxrecs,
> + },
> + {
> + .tag = "refcountbt",
> + .maxlevels = libxfs_refcountbt_maxlevels_ondisk,
> + .maxrecs = refc_maxrecs,
> + },
> + {
> + .tag = "rmapbt",
> + .maxlevels = libxfs_rmapbt_maxlevels_ondisk,
> + .maxrecs = rmap_maxrecs,
> + },
> };
>
> static void
> @@ -55,6 +84,7 @@ btheight_help(void)
> " -n -- Number of records we want to store.\n"
> " -w max -- Show only the best case scenario.\n"
> " -w min -- Show only the worst case scenario.\n"
> +" -w absmax -- Print the maximum possible btree height for all filesystems.\n"
> "\n"
> " Supported btree types:\n"
> " all "
> @@ -232,6 +262,22 @@ _("%s: pointer size must be less than selected block size (%u bytes).\n"),
> #define REPORT_DEFAULT (-1U)
> #define REPORT_MAX (1 << 0)
> #define REPORT_MIN (1 << 1)
> +#define REPORT_ABSMAX (1 << 2)
> +
> +static void
> +report_absmax(const char *tag)
> +{
> + struct btmap *m;
> + int i;
> +
> + for (i = 0, m = maps; i < ARRAY_SIZE(maps); i++, m++) {
> + if (!strcmp(m->tag, tag)) {
> + printf("%s: %u\n", tag, m->maxlevels());
> + return;
> + }
> + }
> + printf(_("%s: Don't know how to report max height.\n"), tag);
> +}
>
> static void
> report(
> @@ -243,6 +289,11 @@ report(
> unsigned int records_per_block[2];
> int ret;
>
> + if (report_what == REPORT_ABSMAX) {
> + report_absmax(tag);
> + return;
> + }
> +
> ret = construct_records_per_block(tag, blocksize, records_per_block);
> if (ret)
> return;
> @@ -344,6 +395,8 @@ btheight_f(
> report_what = REPORT_MIN;
> else if (!strcmp(optarg, "max"))
> report_what = REPORT_MAX;
> + else if (!strcmp(optarg, "absmax"))
> + report_what = REPORT_ABSMAX;
> else {
> btheight_help();
> return 0;
> @@ -355,20 +408,20 @@ btheight_f(
> }
> }
>
> - if (nr_records == 0) {
> + if (report_what != REPORT_ABSMAX && nr_records == 0) {
> fprintf(stderr,
> _("Number of records must be greater than zero.\n"));
> return 0;
> }
>
> - if (blocksize > INT_MAX) {
> + if (report_what != REPORT_ABSMAX && blocksize > INT_MAX) {
> fprintf(stderr,
> _("The largest block size this command will consider is %u bytes.\n"),
> INT_MAX);
> return 0;
> }
>
> - if (blocksize < 128) {
> + if (report_what != REPORT_ABSMAX && blocksize < 128) {
> fprintf(stderr,
> _("The smallest block size this command will consider is 128 bytes.\n"));
> return 0;
> diff --git a/libxfs/libxfs_api_defs.h b/libxfs/libxfs_api_defs.h
> index 0862d4b0..8abbd231 100644
> --- a/libxfs/libxfs_api_defs.h
> +++ b/libxfs/libxfs_api_defs.h
> @@ -23,6 +23,7 @@
> #define xfs_ag_block_count libxfs_ag_block_count
>
> #define xfs_alloc_ag_max_usable libxfs_alloc_ag_max_usable
> +#define xfs_allocbt_maxlevels_ondisk libxfs_allocbt_maxlevels_ondisk
> #define xfs_allocbt_maxrecs libxfs_allocbt_maxrecs
> #define xfs_allocbt_stage_cursor libxfs_allocbt_stage_cursor
> #define xfs_alloc_fix_freelist libxfs_alloc_fix_freelist
> @@ -39,6 +40,7 @@
> #define xfs_bmapi_read libxfs_bmapi_read
> #define xfs_bmapi_write libxfs_bmapi_write
> #define xfs_bmap_last_offset libxfs_bmap_last_offset
> +#define xfs_bmbt_maxlevels_ondisk libxfs_bmbt_maxlevels_ondisk
> #define xfs_bmbt_maxrecs libxfs_bmbt_maxrecs
> #define xfs_bmdr_maxrecs libxfs_bmdr_maxrecs
>
> @@ -109,6 +111,7 @@
> #define xfs_highbit32 libxfs_highbit32
> #define xfs_highbit64 libxfs_highbit64
> #define xfs_ialloc_calc_rootino libxfs_ialloc_calc_rootino
> +#define xfs_iallocbt_maxlevels_ondisk libxfs_iallocbt_maxlevels_ondisk
> #define xfs_idata_realloc libxfs_idata_realloc
> #define xfs_idestroy_fork libxfs_idestroy_fork
> #define xfs_iext_lookup_extent libxfs_iext_lookup_extent
> @@ -138,6 +141,7 @@
> #define xfs_refc_block libxfs_refc_block
> #define xfs_refcountbt_calc_reserves libxfs_refcountbt_calc_reserves
> #define xfs_refcountbt_init_cursor libxfs_refcountbt_init_cursor
> +#define xfs_refcountbt_maxlevels_ondisk libxfs_refcountbt_maxlevels_ondisk
> #define xfs_refcountbt_maxrecs libxfs_refcountbt_maxrecs
> #define xfs_refcountbt_stage_cursor libxfs_refcountbt_stage_cursor
> #define xfs_refcount_get_rec libxfs_refcount_get_rec
> @@ -146,6 +150,7 @@
> #define xfs_rmap_alloc libxfs_rmap_alloc
> #define xfs_rmapbt_calc_reserves libxfs_rmapbt_calc_reserves
> #define xfs_rmapbt_init_cursor libxfs_rmapbt_init_cursor
> +#define xfs_rmapbt_maxlevels_ondisk libxfs_rmapbt_maxlevels_ondisk
> #define xfs_rmapbt_maxrecs libxfs_rmapbt_maxrecs
> #define xfs_rmapbt_stage_cursor libxfs_rmapbt_stage_cursor
> #define xfs_rmap_compare libxfs_rmap_compare
> diff --git a/man/man8/xfs_db.8 b/man/man8/xfs_db.8
> index 55ac3487..1a2bb7e9 100644
> --- a/man/man8/xfs_db.8
> +++ b/man/man8/xfs_db.8
> @@ -402,7 +402,7 @@ If the cursor points at an inode, dump the extended attribute block mapping btre
> Dump all keys and pointers in intermediate btree nodes, and all records in leaf btree nodes.
> .RE
> .TP
> -.BI "btheight [\-b " blksz "] [\-n " recs "] [\-w " max "|\-w " min "] btree types..."
> +.BI "btheight [\-b " blksz "] [\-n " recs "] [\-w " max "|" min "|" absmax "] btree types..."
> For a given number of btree records and a btree type, report the number of
> records and blocks for each level of the btree, and the total number of blocks.
> The btree type must be given after the options.
> @@ -435,6 +435,9 @@ The default is the filesystem block size.
> is used to specify the number of records to store.
> This argument is required.
> .TP
> +.B \-w absmax
> +shows the maximum possible height for the given btree types.
> +.TP
> .B \-w max
> shows only the best case scenario, which is when the btree blocks are
> maximally loaded.
--
chandan
