From 943a7f434b10c19f8e8e865c3cc40685b9903822 Mon Sep 17 00:00:00 2001

From: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

Date: Thu, 24 Mar 2022 17:32:43 -0300

Subject: [PATCH 1/6] Provide a maximum job length depending on the

 virtualization

Identify if a system is running on baremetal or PowerVM and provide

a maximum job length adapted to each case.

Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

---

 lib/nx_inflate.c |  5 +++--

 lib/nx_zlib.c    | 25 +++++++++++++++++++++++--

 lib/nx_zlib.h    |  4 ++++

 3 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/lib/nx_inflate.c b/lib/nx_inflate.c

index ec32b4c..77ad33c 100644

--- a/lib/nx_inflate.c

+++ b/lib/nx_inflate.c

@@ -945,8 +945,9 @@ static int nx_inflate_(nx_streamp s, int flush)

 	uint32_t write_sz, source_sz, target_sz;

 	long loop_cnt = 0, loop_max = 0xffff;

-	/* inflate benefits from large jobs; memcopies must be amortized */

-	uint32_t inflate_per_job_len = 64 * nx_config.per_job_len;

+	/** \brief inflate benefits from large jobs; memcopies must be

+	 *  amortized.  */

+	const uint32_t inflate_per_job_len = nx_config.per_job_len;

 	/* nx hardware */

 	uint32_t sfbt = 0, subc = 0, spbc, tpbc, nx_ce, fc;

diff --git a/lib/nx_zlib.c b/lib/nx_zlib.c

index 28ea482..a50d6f7 100644

--- a/lib/nx_zlib.c

+++ b/lib/nx_zlib.c

@@ -64,6 +64,18 @@

 #include "nx_utils.h"

 #include "nx_zlib.h"

+/* Use the following values as maximum length of NX jobs when the OS doesn't

+   provide the value itself, which is the default behavior until Linux 5.17  */

+

+/** \brief Maximum job length on baremetal

+ *

+ *  While the system does allow up-to 2 GiB as the maximum job length, restrict

+ *  it to 64 MiB.

+ */

+#define DEFAULT_MAX_JOB_BAREMETAL 64 * 1024 * 1024

+/** \brief Maximum job length on PowerVM  */

+#define DEFAULT_MAX_JOB_POWERVM   1024 * 1024

+

 struct nx_config_t nx_config;

 static struct nx_dev_t nx_devices[NX_DEVICES_MAX];

 static int nx_dev_count = 0;

@@ -639,8 +651,13 @@ static int nx_query_job_limits()

 		}

 	}

-	/* On error return default value of 1 MB */

-	return (1024 * 1024);

+	/* On error return default value.  */

+	switch (nx_config.virtualization) {

+		case BAREMETAL:

+			return DEFAULT_MAX_JOB_BAREMETAL;

+		default:

+			return DEFAULT_MAX_JOB_POWERVM;

+	}

 }

 /*

@@ -659,6 +676,9 @@ static int nx_enumerate_engines()

 	int count = 0;

 	size_t n;

+	/* Assume baremetal by default.  */

+	nx_config.virtualization = BAREMETAL;

+

 	d = opendir(DEVICE_TREE);

 	if (d == NULL){

 		prt_err("open device tree dir failed.\n");

@@ -712,6 +732,7 @@ static int nx_enumerate_engines()

 		}

 		/* On PowerVM, there is no concept of multiple NX engines.  */

 		if (strncmp(de->d_name, "ibm,powervm", 11) == 0){

+			nx_config.virtualization = POWERVM;

 			closedir(d);

 			return 1;

 		}

diff --git a/lib/nx_zlib.h b/lib/nx_zlib.h

index e84bd7e..fa73b01 100644

--- a/lib/nx_zlib.h

+++ b/lib/nx_zlib.h

@@ -129,6 +129,8 @@ void nx_print_dde(nx_dde_t *ddep, const char *msg);

 #define zlib_version zlibVersion()

 extern const char *zlibVersion OF((void));

+enum virtualization {BAREMETAL=0, POWERVM=1};

+

 /* common config variables for all streams */

 struct nx_config_t {

 	long     page_sz;

@@ -158,6 +160,8 @@ struct nx_config_t {

 				     * dynamic huffman */

 	struct selector mode; /** mode selector: selects between software

 				* and hardware compression. */

+	uint8_t virtualization; /** Indicate the virtualization type being

+				 *  used. */

 };

 typedef struct nx_config_t *nx_configp_t;

 extern struct nx_config_t nx_config;

From b22eb7bffe61e36f70661921a689e44370d3c7e5 Mon Sep 17 00:00:00 2001

From: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

Date: Thu, 24 Mar 2022 18:03:28 -0300

Subject: [PATCH 2/6] inflate: Move code that initializes the DDE to their own

 functions

Create functions nx_reset_dde() and nx_init_dde() based on previous code

helping to reduce the size of nx_inflate_() and making it easier to

understand the code.

Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

---

 lib/nx_inflate.c | 197 ++++++++++++++++++++++++++++-------------------

 1 file changed, 116 insertions(+), 81 deletions(-)

diff --git a/lib/nx_inflate.c b/lib/nx_inflate.c

index 77ad33c..f1d9adb 100644

--- a/lib/nx_inflate.c

+++ b/lib/nx_inflate.c

@@ -934,6 +934,120 @@ static int copy_data_to_fifo_in(nx_streamp s) {

 	return Z_OK;

 }

+/** \brief Reset DDE to initial values.

+ *

+ *  @param s nx_streamp to be processed.

+ *  @return Function code as passed to CRB. The function will set the CRB and

+ *          return the value here.

+ */

+static int nx_reset_dde(nx_streamp s) {

+	nx_gzip_crb_cpb_t *cmdp = s->nxcmdp;

+	uint32_t fc;

+

+	/* address/len lists */

+	clearp_dde(s->ddl_in);

+	clearp_dde(s->ddl_out);

+

+	/* FC, CRC, HistLen, Table 6-6 */

+	if (s->resuming || (s->dict_len > 0)) {

+		/* Resuming a partially decompressed input.  */

+		fc = GZIP_FC_DECOMPRESS_RESUME;

+	} else {

+		/* First decompress job */

+		fc = GZIP_FC_DECOMPRESS;

+

+		/* We use the most recently measured compression ratio

+		   as a heuristic to estimate the input and output

+		   sizes. If we give too much input, the target buffer

+		   overflows and NX cycles are wasted, and then we

+		   must retry with smaller input size. 1000 is 100% */

+		s->last_comp_ratio = 1000UL;

+	}

+

+	/* clear then copy fc to the crb */

+	cmdp->crb.gzip_fc = 0;

+	putnn(cmdp->crb, gzip_fc, fc);

+

+	return fc;

+}

+

+/** \brief Initialize DDE, appending a dictionary, if necessary.

+ *

+ *  @param s nx_streamp to be processed.

+ *  @return The history length

+ */

+static int nx_init_dde(nx_streamp s) {

+	nx_gzip_crb_cpb_t *cmdp = s->nxcmdp;

+	int nx_history_len = s->history_len;

+

+	/* FC, CRC, HistLen, Table 6-6 */

+	if (s->resuming || (s->dict_len > 0)) {

+		/* Resuming a partially decompressed input.  The key

+		   to resume is supplying the max 32KB dictionary

+		   (history) to NX, which is basically the last 32KB

+		   or less of the output earlier produced. And also

+		   make sure partial checksums are carried forward

+		*/

+

+		/* Crc of prev job passed to the job to be resumed */

+		put32(cmdp->cpb, in_crc, s->crc32);

+		put32(cmdp->cpb, in_adler, s->adler32);

+

+		/* Round up the sizes to quadword. Section 2.10

+		   Rounding up will not segfault because

+		   nx_alloc_buffer has padding at the beginning */

+

+		if (s->dict_len > 0) {

+			/* lays dict on top of hist */

+			nx_history_len = nx_amend_history_with_dict(s);

+

+			if (s->wrap == HEADER_ZLIB) {

+				/* in the raw mode pass crc as is; in the zlib

+				   mode initialize them */

+				put32(cmdp->cpb, in_crc, INIT_CRC );

+				put32(cmdp->cpb, in_adler, INIT_ADLER);

+				put32(cmdp->cpb, out_crc, INIT_CRC );

+				put32(cmdp->cpb, out_adler, INIT_ADLER);

+			}

+			print_dbg_info(s, __LINE__);

+		} else {

+			/* no dictionary here */

+			ASSERT( s->dict_len == 0 );

+			nx_history_len = (nx_history_len + NXQWSZ - 1) / NXQWSZ;

+			putnn(cmdp->cpb, in_histlen, nx_history_len);

+			/* convert to bytes */

+			nx_history_len = nx_history_len * NXQWSZ;

+

+			if (nx_history_len > 0) {

+				/* deflate history goes in first */

+				ASSERT(s->cur_out >= nx_history_len);

+				nx_append_dde(s->ddl_in,

+					      s->fifo_out + (s->cur_out

+							     - nx_history_len),

+					      nx_history_len);

+			}

+			print_dbg_info(s, __LINE__);

+		}

+	} else {

+		nx_history_len = s->history_len = 0;

+		/* writing a 0 clears out subc as well */

+		cmdp->cpb.in_histlen = 0;

+

+		/* initialize the crc values */

+		put32(cmdp->cpb, in_crc, INIT_CRC );

+		put32(cmdp->cpb, in_adler, INIT_ADLER);

+		put32(cmdp->cpb, out_crc, INIT_CRC );

+		put32(cmdp->cpb, out_adler, INIT_ADLER);

+	}

+

+	/* We use the most recently measured compression ratio as a heuristic

+	   to estimate the input and output sizes. If we give too much input,

+	   the target buffer overflows and NX cycles are wasted, and then we

+	   must retry with smaller input size. 1000 is 100% */

+	s->last_comp_ratio = NX_MAX(NX_MIN(1000UL, s->last_comp_ratio), 100L);

+	return nx_history_len;

+}

+

 /** \brief Internal implementation of inflate.

  *

  * @param s nx_streamp to be processed.

@@ -1075,87 +1189,8 @@ static int nx_inflate_(nx_streamp s, int flush)

 	/* NX decompresses input data */

-	/* address/len lists */

-	clearp_dde(ddl_in);

-	clearp_dde(ddl_out);

-

-	nx_history_len = s->history_len;

-

-	/* FC, CRC, HistLen, Table 6-6 */

-	if (s->resuming || (s->dict_len > 0)) {

-		/* Resuming a partially decompressed input.  The key

-		   to resume is supplying the max 32KB dictionary

-		   (history) to NX, which is basically the last 32KB

-		   or less of the output earlier produced. And also

-		   make sure partial checksums are carried forward

-		*/

-		fc = GZIP_FC_DECOMPRESS_RESUME;

-

-		/* Crc of prev job passed to the job to be resumed */

-		put32(cmdp->cpb, in_crc, s->crc32);

-		put32(cmdp->cpb, in_adler, s->adler32);

-

-		/* Round up the sizes to quadword. Section 2.10

-		   Rounding up will not segfault because

-		   nx_alloc_buffer has padding at the beginning */

-

-		if (s->dict_len > 0) {

-			/* lays dict on top of hist */

-			nx_history_len = nx_amend_history_with_dict(s);

-

-			if (s->wrap == HEADER_ZLIB) {

-				/* in the raw mode pass crc as is; in the zlib mode

-				   initialize them */

-				put32(cmdp->cpb, in_crc, INIT_CRC );

-				put32(cmdp->cpb, in_adler, INIT_ADLER);

-				put32(cmdp->cpb, out_crc, INIT_CRC );

-				put32(cmdp->cpb, out_adler, INIT_ADLER);

-			}

-

-			s->last_comp_ratio = NX_MAX( NX_MIN(1000UL, s->last_comp_ratio), 100L );

-

-			print_dbg_info(s, __LINE__);

-		}

-		else {

-			/* no dictionary here */

-			ASSERT( s->dict_len == 0 );

-			nx_history_len = (nx_history_len + NXQWSZ - 1) / NXQWSZ;

-			putnn(cmdp->cpb, in_histlen, nx_history_len);

-			nx_history_len = nx_history_len * NXQWSZ; /* convert to bytes */

-

-			if (nx_history_len > 0) {

-				/* deflate history goes in first */

-				ASSERT(s->cur_out >= nx_history_len);

-				nx_append_dde(ddl_in, s->fifo_out + (s->cur_out - nx_history_len), nx_history_len);

-			}

-			print_dbg_info(s, __LINE__);

-		}

-	}

-	else {

-		/* First decompress job */

-		fc = GZIP_FC_DECOMPRESS;

-

-		nx_history_len = s->history_len = 0;

-		/* writing a 0 clears out subc as well */

-		cmdp->cpb.in_histlen = 0;

-

-		/* initialize the crc values */

-		put32(cmdp->cpb, in_crc, INIT_CRC );

-		put32(cmdp->cpb, in_adler, INIT_ADLER);

-		put32(cmdp->cpb, out_crc, INIT_CRC );

-		put32(cmdp->cpb, out_adler, INIT_ADLER);

-

-		/* We use the most recently measured compression ratio

-		   as a heuristic to estimate the input and output

-		   sizes. If we give too much input, the target buffer

-		   overflows and NX cycles are wasted, and then we

-		   must retry with smaller input size. 1000 is 100% */

-		s->last_comp_ratio = 1000UL;

-	}

-

-	/* clear then copy fc to the crb */

-	cmdp->crb.gzip_fc = 0;

-	putnn(cmdp->crb, gzip_fc, fc);

+	fc = nx_reset_dde(s);

+	nx_history_len = nx_init_dde(s);

 	/*

 	 * NX source buffers

From e376d92fa704108f1258e3a41fc1ffcf551d1c5b Mon Sep 17 00:00:00 2001

From: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

Date: Fri, 25 Mar 2022 09:57:32 -0300

Subject: [PATCH 3/6] Fix the total amount of pages being touched

Fix and error in nx_touch_pages_dde() that was causing the function to

touch a different number of pages than requested.

Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

---

 lib/nx_zlib.c | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/nx_zlib.c b/lib/nx_zlib.c

index a50d6f7..bf2a6fc 100644

--- a/lib/nx_zlib.c

+++ b/lib/nx_zlib.c

@@ -398,7 +398,7 @@ int nx_touch_pages_dde(nx_dde_t *ddep, long buf_sz, long page_sz, int wr)

 		/* touching fewer pages than encoded in the ddebc */

 		if ( total > buf_sz) {

-			buf_len = NX_MIN(buf_len, total - buf_sz);

+			buf_len = buf_sz - (total - buf_len);

 			nx_touch_pages((void *)buf_addr, buf_len, page_sz, wr);

 			prt_trace("touch loop break len 0x%x ddead %p\n", buf_len, (void *)buf_addr);

 			break;

From 1f3dc128a476c9bbbb1b503d2fc8f54365101ebf Mon Sep 17 00:00:00 2001

From: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

Date: Thu, 24 Mar 2022 18:18:34 -0300

Subject: [PATCH 4/6] inflate: Move code that sets the DDE

Create functions nx_set_dde_in() and nx_set_dde_out() based on old code.

Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

---

 lib/nx_inflate.c | 64 +++++++++++++++++++++++++++++++++---------------

 1 file changed, 44 insertions(+), 20 deletions(-)

diff --git a/lib/nx_inflate.c b/lib/nx_inflate.c

index f1d9adb..a9671b2 100644

--- a/lib/nx_inflate.c

+++ b/lib/nx_inflate.c

@@ -1048,6 +1048,41 @@ static int nx_init_dde(nx_streamp s) {

 	return nx_history_len;

 }

+/** \brief Append input data to DDE

+ *

+ *  @param s nx_streamp to be processed.

+ *

+ *  @return The total amount of bytes appended to DDE

+ */

+static uint32_t nx_set_dde_in(nx_streamp s) {

+	/* Buffered user input is next */

+	if (s->fifo_in != NULL)

+		nx_append_dde(s->ddl_in, s->fifo_in + s->cur_in, s->used_in);

+	/* Then current user input.  */

+	nx_append_dde(s->ddl_in, s->next_in, s->avail_in);

+	/* Total bytes going in to engine.  */

+	return getp32(s->ddl_in, ddebc);

+}

+

+/** \brief Append output data to DDE

+ *

+ *  @param s nx_streamp to be processed.

+ *

+ *  @return The total amount of bytes appended to DDE

+ */

+static uint32_t nx_set_dde_out(nx_streamp s) {

+	/* Decompress to user buffer first.  */

+	nx_append_dde(s->ddl_out, s->next_out, s->avail_out);

+

+	/* Overflow to fifo_out.

+	   used_out == 0 required by definition.  */

+	ASSERT(s->used_out == 0);

+	nx_append_dde(s->ddl_out, s->fifo_out + s->cur_out,

+		      s->len_out - s->cur_out);

+

+	return s->avail_out + s->len_out - s->cur_out;

+}

+

 /** \brief Internal implementation of inflate.

  *

  * @param s nx_streamp to be processed.

@@ -1195,28 +1230,13 @@ static int nx_inflate_(nx_streamp s, int flush)

 	/*

 	 * NX source buffers

 	 */

-	/* buffered user input is next */

-	if (s->fifo_in != NULL)

-		nx_append_dde(ddl_in, s->fifo_in + s->cur_in, s->used_in);

-	/* then current user input */

-	nx_append_dde(ddl_in, s->next_in, s->avail_in);

-	source_sz = getp32(ddl_in, ddebc); /* total bytes going in to engine */

-	ASSERT( source_sz > nx_history_len );

+	source_sz = nx_set_dde_in(s);

+	ASSERT(source_sz > nx_history_len);

 	/*

 	 * NX target buffers

 	 */

-	ASSERT(s->used_out == 0);

-

-	uint32_t len_next_out = s->avail_out;

-	nx_append_dde(ddl_out, s->next_out, len_next_out); /* decomp in to user buffer */

-

-	/* overflow, used_out == 0 required by definition, +used_out below is unnecessary */

-	nx_append_dde(ddl_out, s->fifo_out + s->cur_out + s->used_out, s->len_out - s->cur_out - s->used_out);

-	target_sz = len_next_out + s->len_out - s->cur_out - s->used_out;

-

-	prt_info("len_next_out %d len_out %d cur_out %d used_out %d source_sz %d history_len %d\n",

-		 len_next_out, s->len_out, s->cur_out, s->used_out, source_sz, nx_history_len);

+	target_sz = nx_set_dde_out(s);

 	/* We want exactly the History size amount of 32KB to overflow

 	   in to fifo_out.  If overflow is less, the history spans

@@ -1228,6 +1248,7 @@ static int nx_inflate_(nx_streamp s, int flush)

 	   these copies (memcpy) for performance. Therefore, the

 	   heuristic here will estimate the source size for the

 	   desired target size */

+	uint32_t len_next_out = s->avail_out;

 	/* avail_out plus 32 KB history plus a bit of overhead */

 	uint32_t target_sz_expected = len_next_out + INF_HIS_LEN + (INF_HIS_LEN >> 2);

@@ -1240,11 +1261,14 @@ static int nx_inflate_(nx_streamp s, int flush)

 	prt_info("target_sz_expected %d source_sz_expected %d source_sz %d last_comp_ratio %d nx_history_len %d\n", target_sz_expected, source_sz_expected, source_sz, s->last_comp_ratio, nx_history_len);

+	prt_info("%s:%d len_next_out %d len_out %d cur_out %d"

+		 " used_out %d source_sz %d history_len %d\n",

+		 __FUNCTION__, __LINE__, len_next_out, s->len_out, s->cur_out,

+		 s->used_out, source_sz, nx_history_len);

+

 	/* do not include input side history in the estimation */

 	source_sz = source_sz - nx_history_len;

-

 	ASSERT(source_sz > 0);

-

 	source_sz = NX_MIN(source_sz, source_sz_expected);

 	/* add the history back */

From eb6cb7b01fe1fa337979353e905e3ad96514b233 Mon Sep 17 00:00:00 2001

From: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

Date: Thu, 24 Mar 2022 18:37:27 -0300

Subject: [PATCH 5/6] inflate: cosmetic improvements

- Add source code comments.

- Improve indentation.

- Break long lines.

- Fix error and information messages.

Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

---

 lib/nx_inflate.c | 51 ++++++++++++++++++++++++++++++++++++------------

 1 file changed, 38 insertions(+), 13 deletions(-)

diff --git a/lib/nx_inflate.c b/lib/nx_inflate.c

index a9671b2..a6070bd 100644

--- a/lib/nx_inflate.c

+++ b/lib/nx_inflate.c

@@ -1090,14 +1090,31 @@ static uint32_t nx_set_dde_out(nx_streamp s) {

  */

 static int nx_inflate_(nx_streamp s, int flush)

 {

-	/* queuing, file ops, byte counting */

-	uint32_t write_sz, source_sz, target_sz;

+	/** \brief Sum of the bytes that may be used by NX as input

+	 *

+	 *  Total amount of bytes sent to the NX to be used as input,

+	 *  i.e. sum of the bytes in next_in and fifo_in.  */

+	uint32_t source_sz;

+

+	/** \brief Sum of the bytes that may be used by NX as output

+	 *

+	 *  Maximum amount of bytes available by the NX to be used as output,

+	 *  i.e. sum of the bytes available in next_out and fifo_out.  */

+	uint32_t target_sz;

+

+	uint32_t write_sz;

 	long loop_cnt = 0, loop_max = 0xffff;

 	/** \brief inflate benefits from large jobs; memcopies must be

 	 *  amortized.  */

 	const uint32_t inflate_per_job_len = nx_config.per_job_len;

+	/** \brief Estimated value for target_sz. Used to calculate

+	 *  source_sz_expected.  */

+	uint32_t target_sz_expected;

+	/** \brief Estimated value for source_sz.  */

+	uint32_t source_sz_expected;

+

 	/* nx hardware */

 	uint32_t sfbt = 0, subc = 0, spbc, tpbc, nx_ce, fc;

@@ -1251,16 +1268,20 @@ static int nx_inflate_(nx_streamp s, int flush)

 	uint32_t len_next_out = s->avail_out;

 	/* avail_out plus 32 KB history plus a bit of overhead */

-	uint32_t target_sz_expected = len_next_out + INF_HIS_LEN + (INF_HIS_LEN >> 2);

+	target_sz_expected = len_next_out + INF_HIS_LEN + (INF_HIS_LEN >> 2);

 	target_sz_expected = NX_MIN(target_sz_expected, inflate_per_job_len);

 	/* e.g. if we want 100KB at the output and if the compression

 	   ratio is 10% we want 10KB if input */

-	uint32_t source_sz_expected = (uint32_t)(((uint64_t)target_sz_expected * s->last_comp_ratio + 1000L)/1000UL);

+	source_sz_expected = (uint32_t) (((uint64_t) target_sz_expected

+					  * s->last_comp_ratio + 1000L)/1000UL);

-	prt_info("target_sz_expected %d source_sz_expected %d source_sz %d last_comp_ratio %d nx_history_len %d\n", target_sz_expected, source_sz_expected, source_sz, s->last_comp_ratio, nx_history_len);

+	prt_info("%s:%d target_sz_expected %d source_sz_expected %d"

+		 " source_sz %d last_comp_ratio %d nx_history_len %d\n",

+		 __FUNCTION__, __LINE__, target_sz_expected, source_sz_expected,

+		 source_sz, s->last_comp_ratio, nx_history_len);

 	prt_info("%s:%d len_next_out %d len_out %d cur_out %d"

 		 " used_out %d source_sz %d history_len %d\n",

 		 __FUNCTION__, __LINE__, len_next_out, s->len_out, s->cur_out,

@@ -1280,8 +1301,11 @@ static int nx_inflate_(nx_streamp s, int flush)

 	/* fault in pages */

 	nx_touch_pages_dde(ddl_in, source_sz, nx_config.page_sz, 0);

-	nx_touch_pages_dde(ddl_out, target_sz, nx_config.page_sz, 1);

-	nx_touch_pages( (void *)cmdp, sizeof(nx_gzip_crb_cpb_t), nx_config.page_sz, 0);

+	nx_touch_pages_dde(ddl_out,

+			   target_sz,

+			   nx_config.page_sz, 1);

+	nx_touch_pages((void *) cmdp, sizeof(nx_gzip_crb_cpb_t),

+		       nx_config.page_sz, 0);

 	/*

 	 * send job to NX

@@ -1298,9 +1322,9 @@ static int nx_inflate_(nx_streamp s, int flush)

 		   faulting address to fsaddr */

 		print_dbg_info(s, __LINE__);

-		prt_warn("ERR_NX_AT_FAULT: crb.csb.fsaddr %p source_sz %d ",

-			 (void *)cmdp->crb.csb.fsaddr, source_sz);

-		prt_warn("target_sz %d\n", target_sz);

+		prt_warn("ERR_NX_AT_FAULT: crb.csb.fsaddr %p source_sz %d "

+			 "target_sz %d\n", (void *)cmdp->crb.csb.fsaddr,

+			 source_sz, target_sz);

 #ifdef NX_LOG_SOURCE_TARGET

 		nx_print_dde(ddl_in, "source");

 		nx_print_dde(ddl_out, "target");

@@ -1339,8 +1363,8 @@ static int nx_inflate_(nx_streamp s, int flush)

 			if (ticks_total > (timeout_pgfaults * nx_get_freq())) {

 			   /* TODO what to do when page faults are too many?

 			    * Kernel MM would have killed the process. */

-				prt_err("Cannot make progress; too many page");

-				prt_err(" faults cc= %d\n", cc);

+				prt_err("Cannot make progress; too many page"

+					" faults cc= %d\n", cc);

 			}

 			else {

 				prt_warn("ERR_NX_AT_FAULT: more retry\n");

@@ -1397,7 +1421,8 @@ static int nx_inflate_(nx_streamp s, int flush)

 		   cover the max expansion of INF_MIN_INPUT_LEN

 		   bytes */

-		prt_info("ERR_NX_TARGET_SPACE; retry with smaller input data src %d hist %d\n", source_sz, nx_history_len);

+		prt_info("ERR_NX_TARGET_SPACE; retry with smaller input data"

+			 " src %d hist %d\n", source_sz, nx_history_len);

 		goto restart_nx;

 	case ERR_NX_OK:

From 806bf8e3ed1d0ae8a21bc6b2035df390f1062c26 Mon Sep 17 00:00:00 2001

From: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

Date: Mon, 28 Mar 2022 18:15:37 -0300

Subject: [PATCH 6/6] inflate: Limit the amount of data added to the DDE

Stop adding all input and output data to the DDE and limit based on the

calculated value for source_sz_expected and target_sz_expected.

By limiting these values, we end up better estimating the amount of

pages that need to be touched, reducing the amount of time spent

touching pages that might not be used.

Reported-by: Puvichakravarthy Ramachandran <puvichakravarthy@in.ibm.com>

Reported-by: Poorna Chandra Vemula <Poorna.Chandra.Vemula@ibm.com>

Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>

---

 lib/nx_inflate.c | 180 +++++++++++++++++++++++++++++------------------

 1 file changed, 111 insertions(+), 69 deletions(-)

diff --git a/lib/nx_inflate.c b/lib/nx_inflate.c

index a6070bd..b30cdf6 100644

--- a/lib/nx_inflate.c

+++ b/lib/nx_inflate.c

@@ -955,13 +955,6 @@ static int nx_reset_dde(nx_streamp s) {

 	} else {

 		/* First decompress job */

 		fc = GZIP_FC_DECOMPRESS;

-

-		/* We use the most recently measured compression ratio

-		   as a heuristic to estimate the input and output

-		   sizes. If we give too much input, the target buffer

-		   overflows and NX cycles are wasted, and then we

-		   must retry with smaller input size. 1000 is 100% */

-		s->last_comp_ratio = 1000UL;

 	}

 	/* clear then copy fc to the crb */

@@ -1051,15 +1044,24 @@ static int nx_init_dde(nx_streamp s) {

 /** \brief Append input data to DDE

  *

  *  @param s nx_streamp to be processed.

+ *  @param source_sz_expected The total amount of bytes expected as input. It

+ *         does not include dictionary or history.

  *

  *  @return The total amount of bytes appended to DDE

  */

-static uint32_t nx_set_dde_in(nx_streamp s) {

+static uint32_t nx_set_dde_in(nx_streamp s, uint32_t source_sz_expected) {

+	uint32_t tmp = 0;

+

 	/* Buffered user input is next */

-	if (s->fifo_in != NULL)

-		nx_append_dde(s->ddl_in, s->fifo_in + s->cur_in, s->used_in);

-	/* Then current user input.  */

-	nx_append_dde(s->ddl_in, s->next_in, s->avail_in);

+	if (s->fifo_in != NULL) {

+		tmp = NX_MIN(s->used_in, source_sz_expected);

+		nx_append_dde(s->ddl_in, s->fifo_in + s->cur_in, tmp);

+	}

+	if (tmp < source_sz_expected) {

+		tmp = NX_MIN(s->avail_in, source_sz_expected - tmp);

+		/* Then current user input.  */

+		nx_append_dde(s->ddl_in, s->next_in, tmp);

+	}

 	/* Total bytes going in to engine.  */

 	return getp32(s->ddl_in, ddebc);

 }

@@ -1067,20 +1069,32 @@ static uint32_t nx_set_dde_in(nx_streamp s) {

 /** \brief Append output data to DDE

  *

  *  @param s nx_streamp to be processed.

+ *  @param target_sz_expected The total amount of bytes expected as output.

  *

  *  @return The total amount of bytes appended to DDE

  */

-static uint32_t nx_set_dde_out(nx_streamp s) {

+static uint32_t nx_set_dde_out(nx_streamp s, uint32_t target_sz_expected) {

+	uint32_t tmp;

+	uint32_t ret;

+

+	ret = NX_MIN(s->avail_out, target_sz_expected);

+

 	/* Decompress to user buffer first.  */

-	nx_append_dde(s->ddl_out, s->next_out, s->avail_out);

+	nx_append_dde(s->ddl_out, s->next_out, ret);

+

+	if (ret < target_sz_expected) {

+		tmp = NX_MIN(s->len_out - s->cur_out,

+			     target_sz_expected - ret);

+

+		/* Overflow to fifo_out.

+		   used_out == 0 required by definition.  */

+		ASSERT(s->used_out == 0);

+		nx_append_dde(s->ddl_out, s->fifo_out + s->cur_out, tmp);

-	/* Overflow to fifo_out.

-	   used_out == 0 required by definition.  */

-	ASSERT(s->used_out == 0);

-	nx_append_dde(s->ddl_out, s->fifo_out + s->cur_out,

-		      s->len_out - s->cur_out);

+		ret += tmp;

+	}

-	return s->avail_out + s->len_out - s->cur_out;

+	return ret;

 }

 /** \brief Internal implementation of inflate.

@@ -1094,7 +1108,7 @@ static int nx_inflate_(nx_streamp s, int flush)