[PATCH] eal/linux: fix HPET symbols export

[PATCH] eal/linux: fix HPET symbols export

[David Marchand]

The .map generation script has no clue about build configuration as it
relies only on the presence of RTE_EXPORT* and RTE_VERSION* markers in
a source file.

As a consequence, Linux eal_exports.map contains references to
HPET symbols regardless of the use_hpet meson option value.

$ meson configure build -Duse_hpet=false
$ ninja -C build
...
$ grep hpet build/lib/eal_exports.map
	rte_eal_hpet_init;
	rte_get_hpet_cycles;
	rte_get_hpet_hz;

As far as I have seen, superfluous exports have no impact on generating
a shared library with the GNU linker, yet it might be different with
other linkers (MSVC linker would complain, for example).

Moving those symbols to a dedicated source file solves this (non?) issue.

Fixes: 57c194d142d9 ("build: use dynamically generated version maps")

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 lib/eal/linux/eal_timer.c      | 175 --------------------------------
 lib/eal/linux/eal_timer_hpet.c | 179 +++++++++++++++++++++++++++++++++
 lib/eal/linux/meson.build      |   4 +
 3 files changed, 183 insertions(+), 175 deletions(-)
 create mode 100644 lib/eal/linux/eal_timer_hpet.c

diff --git a/lib/eal/linux/eal_timer.c b/lib/eal/linux/eal_timer.c
index 0e670a0af6..39f975b6b9 100644
--- a/lib/eal/linux/eal_timer.c
+++ b/lib/eal/linux/eal_timer.c
@@ -6,11 +6,6 @@
 #include <stdio.h>
 #include <stdint.h>
 #include <inttypes.h>
-#ifdef RTE_LIBEAL_USE_HPET
-#include <fcntl.h>
-#include <sys/mman.h>
-#include <unistd.h>
-#endif
 
 #include <rte_common.h>
 #include <rte_cycles.h>
@@ -22,176 +17,6 @@
 RTE_EXPORT_SYMBOL(eal_timer_source)
 enum timer_source eal_timer_source = EAL_TIMER_HPET;
 
-#ifdef RTE_LIBEAL_USE_HPET
-
-#define DEV_HPET "/dev/hpet"
-
-/* Maximum number of counters. */
-#define HPET_TIMER_NUM 3
-
-/* General capabilities register */
-#define CLK_PERIOD_SHIFT     32 /* Clock period shift. */
-#define CLK_PERIOD_MASK      0xffffffff00000000ULL /* Clock period mask. */
-
-/**
- * HPET timer registers. From the Intel IA-PC HPET (High Precision Event
- * Timers) Specification.
- */
-struct eal_hpet_regs {
-	/* Memory-mapped, software visible registers */
-	uint64_t capabilities;      /**< RO General Capabilities Register. */
-	uint64_t reserved0;         /**< Reserved for future use. */
-	uint64_t config;            /**< RW General Configuration Register. */
-	uint64_t reserved1;         /**< Reserved for future use. */
-	uint64_t isr;               /**< RW Clear General Interrupt Status. */
-	uint64_t reserved2[25];     /**< Reserved for future use. */
-	union {
-		uint64_t counter;   /**< RW Main Counter Value Register. */
-		struct {
-			uint32_t counter_l; /**< RW Main Counter Low. */
-			uint32_t counter_h; /**< RW Main Counter High. */
-		};
-	};
-	uint64_t reserved3;         /**< Reserved for future use. */
-	struct {
-		uint64_t config;    /**< RW Timer Config and Capability Reg. */
-		uint64_t comp;      /**< RW Timer Comparator Value Register. */
-		uint64_t fsb;       /**< RW FSB Interrupt Route Register. */
-		uint64_t reserved4; /**< Reserved for future use. */
-	} timers[HPET_TIMER_NUM]; /**< Set of HPET timers. */
-};
-
-/* Mmap'd hpet registers */
-static volatile struct eal_hpet_regs *eal_hpet = NULL;
-
-/* Period at which the HPET counter increments in
- * femtoseconds (10^-15 seconds). */
-static uint32_t eal_hpet_resolution_fs = 0;
-
-/* Frequency of the HPET counter in Hz */
-static uint64_t eal_hpet_resolution_hz = 0;
-
-/* Incremented 4 times during one 32bits hpet full count */
-static uint32_t eal_hpet_msb;
-
-static rte_thread_t msb_inc_thread_id;
-
-/*
- * This function runs on a specific thread to update a global variable
- * containing used to process MSB of the HPET (unfortunately, we need
- * this because hpet is 32 bits by default under linux).
- */
-static uint32_t
-hpet_msb_inc(__rte_unused void *arg)
-{
-	uint32_t t;
-
-	while (1) {
-		t = (eal_hpet->counter_l >> 30);
-		if (t != (eal_hpet_msb & 3))
-			eal_hpet_msb ++;
-		sleep(10);
-	}
-	return 0;
-}
-
-RTE_EXPORT_SYMBOL(rte_get_hpet_hz)
-uint64_t
-rte_get_hpet_hz(void)
-{
-	const struct internal_config *internal_conf =
-		eal_get_internal_configuration();
-
-	if (internal_conf->no_hpet)
-		rte_panic("Error, HPET called, but no HPET present\n");
-
-	return eal_hpet_resolution_hz;
-}
-
-RTE_EXPORT_SYMBOL(rte_get_hpet_cycles)
-uint64_t
-rte_get_hpet_cycles(void)
-{
-	uint32_t t, msb;
-	uint64_t ret;
-	const struct internal_config *internal_conf =
-		eal_get_internal_configuration();
-
-	if (internal_conf->no_hpet)
-		rte_panic("Error, HPET called, but no HPET present\n");
-
-	t = eal_hpet->counter_l;
-	msb = eal_hpet_msb;
-	ret = (msb + 2 - (t >> 30)) / 4;
-	ret <<= 32;
-	ret += t;
-	return ret;
-}
-
-#endif
-
-#ifdef RTE_LIBEAL_USE_HPET
-/*
- * Open and mmap /dev/hpet (high precision event timer) that will
- * provide our time reference.
- */
-RTE_EXPORT_SYMBOL(rte_eal_hpet_init)
-int
-rte_eal_hpet_init(int make_default)
-{
-	int fd, ret;
-	struct internal_config *internal_conf =
-		eal_get_internal_configuration();
-
-	if (internal_conf->no_hpet) {
-		EAL_LOG(NOTICE, "HPET is disabled");
-		return -1;
-	}
-
-	fd = open(DEV_HPET, O_RDONLY);
-	if (fd < 0) {
-		EAL_LOG(ERR, "ERROR: Cannot open "DEV_HPET": %s!",
-			strerror(errno));
-		internal_conf->no_hpet = 1;
-		return -1;
-	}
-	eal_hpet = mmap(NULL, 1024, PROT_READ, MAP_SHARED, fd, 0);
-	if (eal_hpet == MAP_FAILED) {
-		EAL_LOG(ERR, "ERROR: Cannot mmap "DEV_HPET"!");
-		close(fd);
-		internal_conf->no_hpet = 1;
-		return -1;
-	}
-	close(fd);
-
-	eal_hpet_resolution_fs = (uint32_t)((eal_hpet->capabilities &
-					CLK_PERIOD_MASK) >>
-					CLK_PERIOD_SHIFT);
-
-	eal_hpet_resolution_hz = (1000ULL*1000ULL*1000ULL*1000ULL*1000ULL) /
-		(uint64_t)eal_hpet_resolution_fs;
-
-	EAL_LOG(INFO, "HPET frequency is ~%"PRIu64" kHz",
-			eal_hpet_resolution_hz/1000);
-
-	eal_hpet_msb = (eal_hpet->counter_l >> 30);
-
-	/* create a thread that will increment a global variable for
-	 * msb (hpet is 32 bits by default under linux) */
-	ret = rte_thread_create_internal_control(&msb_inc_thread_id, "hpet-msb",
-			hpet_msb_inc, NULL);
-	if (ret != 0) {
-		EAL_LOG(ERR, "ERROR: Cannot create HPET timer thread!");
-		internal_conf->no_hpet = 1;
-		return -1;
-	}
-
-	if (make_default)
-		eal_timer_source = EAL_TIMER_HPET;
-	return 0;
-}
-#endif
-
 /* Check if the kernel deems the arch provided TSC frequency trustworthy. */
 
 static bool
diff --git a/lib/eal/linux/eal_timer_hpet.c b/lib/eal/linux/eal_timer_hpet.c
new file mode 100644
index 0000000000..63e38bd53e
--- /dev/null
+++ b/lib/eal/linux/eal_timer_hpet.c
@@ -0,0 +1,179 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2010-2014 Intel Corporation.
+ * Copyright(c) 2012-2013 6WIND S.A.
+ */
+
+#include <fcntl.h>
+#include <inttypes.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include <rte_cycles.h>
+#include <rte_thread.h>
+
+#include <eal_export.h>
+#include "eal_private.h"
+
+#define DEV_HPET "/dev/hpet"
+
+/* Maximum number of counters. */
+#define HPET_TIMER_NUM 3
+
+/* General capabilities register */
+#define CLK_PERIOD_SHIFT     32 /* Clock period shift. */
+#define CLK_PERIOD_MASK      0xffffffff00000000ULL /* Clock period mask. */
+
+/**
+ * HPET timer registers. From the Intel IA-PC HPET (High Precision Event
+ * Timers) Specification.
+ */
+struct eal_hpet_regs {
+	/* Memory-mapped, software visible registers */
+	uint64_t capabilities;      /**< RO General Capabilities Register. */
+	uint64_t reserved0;         /**< Reserved for future use. */
+	uint64_t config;            /**< RW General Configuration Register. */
+	uint64_t reserved1;         /**< Reserved for future use. */
+	uint64_t isr;               /**< RW Clear General Interrupt Status. */
+	uint64_t reserved2[25];     /**< Reserved for future use. */
+	union {
+		uint64_t counter;   /**< RW Main Counter Value Register. */
+		struct {
+			uint32_t counter_l; /**< RW Main Counter Low. */
+			uint32_t counter_h; /**< RW Main Counter High. */
+		};
+	};
+	uint64_t reserved3;         /**< Reserved for future use. */
+	struct {
+		uint64_t config;    /**< RW Timer Config and Capability Reg. */
+		uint64_t comp;      /**< RW Timer Comparator Value Register. */
+		uint64_t fsb;       /**< RW FSB Interrupt Route Register. */
+		uint64_t reserved4; /**< Reserved for future use. */
+	} timers[HPET_TIMER_NUM]; /**< Set of HPET timers. */
+};
+
+/* Mmap'd hpet registers */
+static volatile struct eal_hpet_regs *eal_hpet;
+
+/* Period at which the HPET counter increments in femtoseconds (10^-15 seconds). */
+static uint32_t eal_hpet_resolution_fs;
+
+/* Frequency of the HPET counter in Hz */
+static uint64_t eal_hpet_resolution_hz;
+
+/* Incremented 4 times during one 32bits hpet full count */
+static uint32_t eal_hpet_msb;
+
+static rte_thread_t msb_inc_thread_id;
+
+/*
+ * This function runs on a specific thread to update a global variable
+ * containing used to process MSB of the HPET (unfortunately, we need
+ * this because hpet is 32 bits by default under linux).
+ */
+static uint32_t
+hpet_msb_inc(__rte_unused void *arg)
+{
+	uint32_t t;
+
+	while (1) {
+		t = (eal_hpet->counter_l >> 30);
+		if (t != (eal_hpet_msb & 3))
+			eal_hpet_msb++;
+		sleep(10);
+	}
+	return 0;
+}
+
+RTE_EXPORT_SYMBOL(rte_get_hpet_hz)
+uint64_t
+rte_get_hpet_hz(void)
+{
+	const struct internal_config *internal_conf =
+		eal_get_internal_configuration();
+
+	if (internal_conf->no_hpet)
+		rte_panic("Error, HPET called, but no HPET present\n");
+
+	return eal_hpet_resolution_hz;
+}
+
+RTE_EXPORT_SYMBOL(rte_get_hpet_cycles)
+uint64_t
+rte_get_hpet_cycles(void)
+{
+	uint32_t t, msb;
+	uint64_t ret;
+	const struct internal_config *internal_conf =
+		eal_get_internal_configuration();
+
+	if (internal_conf->no_hpet)
+		rte_panic("Error, HPET called, but no HPET present\n");
+
+	t = eal_hpet->counter_l;
+	msb = eal_hpet_msb;
+	ret = (msb + 2 - (t >> 30)) / 4;
+	ret <<= 32;
+	ret += t;
+	return ret;
+}
+
+/*
+ * Open and mmap /dev/hpet (high precision event timer) that will
+ * provide our time reference.
+ */
+RTE_EXPORT_SYMBOL(rte_eal_hpet_init)
+int
+rte_eal_hpet_init(int make_default)
+{
+	int fd, ret;
+	struct internal_config *internal_conf =
+		eal_get_internal_configuration();
+
+	if (internal_conf->no_hpet) {
+		EAL_LOG(NOTICE, "HPET is disabled");
+		return -1;
+	}
+
+	fd = open(DEV_HPET, O_RDONLY);
+	if (fd < 0) {
+		EAL_LOG(ERR, "ERROR: Cannot open "DEV_HPET": %s!",
+			strerror(errno));
+		internal_conf->no_hpet = 1;
+		return -1;
+	}
+	eal_hpet = mmap(NULL, 1024, PROT_READ, MAP_SHARED, fd, 0);
+	if (eal_hpet == MAP_FAILED) {
+		EAL_LOG(ERR, "ERROR: Cannot mmap "DEV_HPET"!");
+		close(fd);
+		internal_conf->no_hpet = 1;
+		return -1;
+	}
+	close(fd);
+
+	eal_hpet_resolution_fs = (uint32_t)((eal_hpet->capabilities &
+					CLK_PERIOD_MASK) >>
+					CLK_PERIOD_SHIFT);
+
+	eal_hpet_resolution_hz = (1000ULL*1000ULL*1000ULL*1000ULL*1000ULL) /
+		(uint64_t)eal_hpet_resolution_fs;
+
+	EAL_LOG(INFO, "HPET frequency is ~%"PRIu64" kHz",
+			eal_hpet_resolution_hz/1000);
+
+	eal_hpet_msb = (eal_hpet->counter_l >> 30);
+
+	/* create a thread that will increment a global variable for
+	 * msb (hpet is 32 bits by default under linux)
+	 */
+	ret = rte_thread_create_internal_control(&msb_inc_thread_id, "hpet-msb",
+			hpet_msb_inc, NULL);
+	if (ret != 0) {
+		EAL_LOG(ERR, "ERROR: Cannot create HPET timer thread!");
+		internal_conf->no_hpet = 1;
+		return -1;
+	}
+
+	if (make_default)
+		eal_timer_source = EAL_TIMER_HPET;
+	return 0;
+}
diff --git a/lib/eal/linux/meson.build b/lib/eal/linux/meson.build
index e99ebed256..29ba313218 100644
--- a/lib/eal/linux/meson.build
+++ b/lib/eal/linux/meson.build
@@ -19,6 +19,10 @@ sources += files(
         'eal_vfio_mp_sync.c',
 )
 
+if dpdk_conf.get('RTE_LIBEAL_USE_HPET')
+    sources += files('eal_timer_hpet.c')
+endif
+
 deps += ['kvargs', 'telemetry']
 if has_libnuma
     dpdk_conf.set10('RTE_EAL_NUMA_AWARE_HUGEPAGES', true)
-- 
2.53.0

Re: [PATCH] eal/linux: fix HPET symbols export

[David Marchand]

On Wed, 18 Feb 2026 at 11:19, David Marchand <david.marchand@redhat.com> wrote:
>
> The .map generation script has no clue about build configuration as it
> relies only on the presence of RTE_EXPORT* and RTE_VERSION* markers in
> a source file.
>
> As a consequence, Linux eal_exports.map contains references to
> HPET symbols regardless of the use_hpet meson option value.
>
> $ meson configure build -Duse_hpet=false
> $ ninja -C build
> ...
> $ grep hpet build/lib/eal_exports.map
>         rte_eal_hpet_init;
>         rte_get_hpet_cycles;
>         rte_get_hpet_hz;
>
> As far as I have seen, superfluous exports have no impact on generating
> a shared library with the GNU linker, yet it might be different with
> other linkers (MSVC linker would complain, for example).
>
> Moving those symbols to a dedicated source file solves this (non?) issue.
>
> Fixes: 57c194d142d9 ("build: use dynamically generated version maps")
>
> Signed-off-by: David Marchand <david.marchand@redhat.com>

Recheck-request: iol-unit-amd64-testing


-- 
David Marchand

Re: [PATCH] eal/linux: fix HPET symbols export

[fengchengwen]

Acked-by: Chengwen Feng <fengchengwen@huawei.com>

On 2/18/2026 6:18 PM, David Marchand wrote:
> The .map generation script has no clue about build configuration as it
> relies only on the presence of RTE_EXPORT* and RTE_VERSION* markers in
> a source file.
> 
> As a consequence, Linux eal_exports.map contains references to
> HPET symbols regardless of the use_hpet meson option value.
> 
> $ meson configure build -Duse_hpet=false
> $ ninja -C build
> ...
> $ grep hpet build/lib/eal_exports.map
> 	rte_eal_hpet_init;
> 	rte_get_hpet_cycles;
> 	rte_get_hpet_hz;
> 
> As far as I have seen, superfluous exports have no impact on generating
> a shared library with the GNU linker, yet it might be different with
> other linkers (MSVC linker would complain, for example).
> 
> Moving those symbols to a dedicated source file solves this (non?) issue.
> 
> Fixes: 57c194d142d9 ("build: use dynamically generated version maps")
> 
> Signed-off-by: David Marchand <david.marchand@redhat.com>

Re: [PATCH] eal/linux: fix HPET symbols export

[David Marchand]

On Wed, 18 Feb 2026 at 11:19, David Marchand <david.marchand@redhat.com> wrote:
>
> The .map generation script has no clue about build configuration as it
> relies only on the presence of RTE_EXPORT* and RTE_VERSION* markers in
> a source file.
>
> As a consequence, Linux eal_exports.map contains references to
> HPET symbols regardless of the use_hpet meson option value.
>
> $ meson configure build -Duse_hpet=false
> $ ninja -C build
> ...
> $ grep hpet build/lib/eal_exports.map
>         rte_eal_hpet_init;
>         rte_get_hpet_cycles;
>         rte_get_hpet_hz;
>
> As far as I have seen, superfluous exports have no impact on generating
> a shared library with the GNU linker, yet it might be different with
> other linkers (MSVC linker would complain, for example).
>
> Moving those symbols to a dedicated source file solves this (non?) issue.
>
> Fixes: 57c194d142d9 ("build: use dynamically generated version maps")
>
> Signed-off-by: David Marchand <david.marchand@redhat.com>
> Acked-by: Chengwen Feng <fengchengwen@huawei.com>

Applied, thanks.


-- 
David Marchand

Re: [PATCH] eal/linux: fix HPET symbols export

[Ben Magistro]

[-- Attachment #1: Type: text/plain, Size: 2142 bytes --]

Just now getting to cleaning up my mailing list folder and came across this
so apologize for reopening an older thread.  We will likely appreciate the
patch a great deal as we needed to switch to lld form clang (this past
week).  When we made this switch (had some size related issues with
sanitizer builds in our app with ld) lld definitely complained about the
symbols not being defined.

I don't have more of the output saved from when we found this, but did save
off these lines while discussing with the team.

ld.lld: error: version script assignment of 'DPDK_23' to symbol
'rte_eal_hpet_init' failed: symbol not defined
ld.lld: error: version script assignment of 'DPDK_23' to symbol
'rte_get_hpet_cycles' failed: symbol not defined
ld.lld: error: version script assignment of 'DPDK_23' to symbol
'rte_get_hpet_hz' failed: symbol not defined


On Thu, Mar 5, 2026 at 7:30 AM David Marchand <david.marchand@redhat.com>
wrote:

> On Wed, 18 Feb 2026 at 11:19, David Marchand <david.marchand@redhat.com>
> wrote:
> >
> > The .map generation script has no clue about build configuration as it
> > relies only on the presence of RTE_EXPORT* and RTE_VERSION* markers in
> > a source file.
> >
> > As a consequence, Linux eal_exports.map contains references to
> > HPET symbols regardless of the use_hpet meson option value.
> >
> > $ meson configure build -Duse_hpet=false
> > $ ninja -C build
> > ...
> > $ grep hpet build/lib/eal_exports.map
> >         rte_eal_hpet_init;
> >         rte_get_hpet_cycles;
> >         rte_get_hpet_hz;
> >
> > As far as I have seen, superfluous exports have no impact on generating
> > a shared library with the GNU linker, yet it might be different with
> > other linkers (MSVC linker would complain, for example).
> >
> > Moving those symbols to a dedicated source file solves this (non?) issue.
> >
> > Fixes: 57c194d142d9 ("build: use dynamically generated version maps")
> >
> > Signed-off-by: David Marchand <david.marchand@redhat.com>
> > Acked-by: Chengwen Feng <fengchengwen@huawei.com>
>
> Applied, thanks.
>
>
> --
> David Marchand
>
>

[-- Attachment #2: Type: text/html, Size: 2918 bytes --]

Re: [PATCH] eal/linux: fix HPET symbols export

[David Marchand]

Hello,

On Thu, 5 Mar 2026 at 14:21, Ben Magistro <koncept1@gmail.com> wrote:
>
> Just now getting to cleaning up my mailing list folder and came across this so apologize for reopening an older thread.  We will likely appreciate the patch a great deal as we needed to switch to lld form clang (this past week).  When we made this switch (had some size related issues with sanitizer builds in our app with ld) lld definitely complained about the symbols not being defined.
>
> I don't have more of the output saved from when we found this, but did save off these lines while discussing with the team.
>
> ld.lld: error: version script assignment of 'DPDK_23' to symbol 'rte_eal_hpet_init' failed: symbol not defined
> ld.lld: error: version script assignment of 'DPDK_23' to symbol 'rte_get_hpet_cycles' failed: symbol not defined
> ld.lld: error: version script assignment of 'DPDK_23' to symbol 'rte_get_hpet_hz' failed: symbol not defined

.map files were static until v25.07 and you seem to use a version
prior to 23.11 LTS.
The dynamic generation of .map has not been backported, so
unfortunately this current patch will not help in your case.


-- 
David Marchand

Re: [PATCH] eal/linux: fix HPET symbols export

[Ben Magistro]

[-- Attachment #1: Type: text/plain, Size: 1485 bytes --]

We know we are behind on updating our usage of DPDK so this might just help
nudge that along.  Appreciate the heads up though!

Cheers

On Thu, Mar 5, 2026 at 8:43 AM David Marchand <david.marchand@redhat.com>
wrote:

> Hello,
>
> On Thu, 5 Mar 2026 at 14:21, Ben Magistro <koncept1@gmail.com> wrote:
> >
> > Just now getting to cleaning up my mailing list folder and came across
> this so apologize for reopening an older thread.  We will likely appreciate
> the patch a great deal as we needed to switch to lld form clang (this past
> week).  When we made this switch (had some size related issues with
> sanitizer builds in our app with ld) lld definitely complained about the
> symbols not being defined.
> >
> > I don't have more of the output saved from when we found this, but did
> save off these lines while discussing with the team.
> >
> > ld.lld: error: version script assignment of 'DPDK_23' to symbol
> 'rte_eal_hpet_init' failed: symbol not defined
> > ld.lld: error: version script assignment of 'DPDK_23' to symbol
> 'rte_get_hpet_cycles' failed: symbol not defined
> > ld.lld: error: version script assignment of 'DPDK_23' to symbol
> 'rte_get_hpet_hz' failed: symbol not defined
>
> .map files were static until v25.07 and you seem to use a version
> prior to 23.11 LTS.
> The dynamic generation of .map has not been backported, so
> unfortunately this current patch will not help in your case.
>
>
> --
> David Marchand
>
>

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